Evolution of Diet

How Dogs Won The World

gregladen — Fri, 13 Nov 2015 12:44:14 +0000

How Dogs Won The World

Years ago I proposed a theory (not anywhere in print, just in seminars and talks) that went roughly like this. Humans hunt. Dogs hunt. Prey animals get hunted. Each species (or set of species) has a number of characteristics such as the ability to stalk, track, kill, run away, form herds, etc. Now imagine a landscape with humans, wolves, and game animals all carrying out these behaviors, facilitated with various physical traits. Then, go back to the drawing board and redesign the system.

The hunting abilities of humans and dogs, the tendency of game animals to herd up or take other actions to avoid predation, etc., if disassembled and reassembled with the same actors playing somewhat different roles, give you a sheep herder, a protecting breed of dogs (like the Great Pyrenees or other mastiff type breeds), a herding dog (like a border collie) and a bunch of sheep, cattle, or goats.

Even human hunting with dogs (not herding domesticated animals) involves a reorganization of tasks and abilities, all present in non-dog-owning human ancestors and wolves (dog ancestors), but where the game are, as far as we know, unchanged. Human hunters documented in the ethnographic record, all around the world, had or have dogs, and those dogs are essential for many hunting types. The Efe Pygmies, with whom I lived in the Congo for a time, use dogs in their group hunting, where they spook animals into view for killing by archers, or drive them into nets that slow the game down long enough to be killed. The Efe actually get a lot of their game by ambush hunting, where a solitary man waits in a tree for a game animal to visit a nearby food source. He shoots the animal from the tree with an arrow. But, even then, the dog plays a role, because the wounded animal runs away. The trick to successful ambush hunting is to do it fairly near camp so you can call for help when an animal is wounded. Someone sends out a dog, and the dog runs the animal to ground. And so forth.

Scientist and science writer Pat Shipman has proposed another important element that addresses a key question in human evolution. Neanderthals, who were pretty much human like we are in most respect, and our own subspecies (or species, of you like) coexisted, but the Neanderthals were probably better adapted to the cooler European and West Asian environment they lived in. But, humans outcompeted them, or at least, replaced them, in this region very quickly once they arrived. Shipman suggests that it was the emerging dog-human association, with humans domesticating wolves, that allowed this to work. Most remarkably, and either very insightfully or totally fancifully (depending on where the data eventually lead), Shipman suggests that is was the unique human ability to communicate with their gaze that allowed this to happen, or at least, facilitated the human-dog relationship to make it really work. We don't know if Neanderthals had this ability or not, but humans do and are unique among primates. We have whites around our Irises, which allow others to see what we are looking at, looking for, and looking like. We can and do communicate quite effectively, and by the way generally viscerally and honestly, with our glance. This, Shipman proposes, could have been the key bit of glue (or lubricant?) that made the human-dog cooperation happen, or at least, rise to a remarkable level.

The Invaders: How humans and their dogs drove Neanderthals to extinction, by Pat Shipman, outlines this theory. But that is only part of this new book. Shipman also provides a totally up to date and extremely readable, and enjoyable, overview of Neanderthal and contemporary modern human evolution. Shipman incorporates the vast evidence from archaeology, physical anthropology, and genetics to do so, and her book may be the best current source for all of this.

This is a fantastic book, and I highly recommend it. Shipman also wrote "The Animal Connection," "The Evolution of Racism," "The Wisdom of the Bones: In Search of Human Origins," and several other excellent books on human evolution and other topics. Shipman, prior to becoming mainly a science writer, pioneered work in the science of Taphonomy, developing methods for analyzing marks on bones recovered from archaeological and paleontologic sites, such as those marks that may have been left by early hominins using stone tools to butcher animals.

Seriously, go read The Invaders: How humans and their dogs drove Neanderthals to extinction.

gregladen Fri, 11/13/2015 - 07:44

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Books

Dogs

Evolution of Diet

Human Evolution

Neanderthal

Origin of Modern Humans

Must be a great book! Rushing to buy it!

I once had a dog who communicated with her gaze very efficiently. She had medication for gastric problems, and when she felt unwell, would stare at me until I noticed, then turn her gaze to the top of the fridge where the medication was kept. She then looked alternately at me and the medication until I worked out what she wanted and gave her the tablets. She only asked for her medication when she was unwell, and the tablets didn't taste nice so she wasn't trying to get a treat.

The Neanderthals died out because they tried to domesticate the wrong species. So while H. sapiens was forging his productive relationship with wolves, H. neanderthalensis was engaged in a static staring contest with lynxes that alternated between "what?" and "so bored now".

Magma: Good one!

Two big questions here
A) why the assumption that Neanderthals could not communicate with their gaze? These were tool users, teachers, hunters. People who sat arround fires and had complex social interactions. More importantly, they were capable of socializing with humans. If gaze is key to humans, this suggests Neanderthals shared the ability to communicate and facilitate mating.
2) you need to accept an extremely early date for dog domestication to reach this conclusion. Archaeological evidence points to a date c. 15k bp. While genetic evidence may point to domestication just at the time of human neanderthal interaction, it would have been relatively uncommon and very tentative interaction between humans and wolves.

Added to my "to be read" list. Thanks, Greg.

What about cats?

Magma, you might be on to something.

Thadd, good questions. Shipman's idea does not rely on the quirk that the unique human trait (the whites of our eyes) emerged in humans and not neanderthals, but it is what she suggests as a possibility.

Neanderthals may not have simply been just like humans. Whether we think they were or not is more a matter of fad at this point, though I think no one sees them as senseless brutes any more.

Humans have a collection of traits. There is no clear way to know which needed to co-evolve. Hard to say which unique human traits they may have not had, and visa versa.

i don't have a problem with the dating of dog domestication. It has to be early and widespread if all foragers colonized all lands with them. (If that happened). The archaeological dates do not really inform us. Read Shipman's arguments on that.

Looks interesting! Thanks for sharing.

Every year, I make an introductory lesson on evolutionary biology to my students in physical chemistry. The focus is "what makes humans peculiar animals". And there are lots of features that are peculiar to humans; a very curious species. The whites of our eyes are a nice addition to the list, Others are the prorturing chin, the large number of sweating glands, the lack of a baculum in males, and more. Most are easily explainable in terms of evolutionary biology, some are rather hard: why did we (males) lose our penile bone? There are explanations, but none really convincing

Fascinating post, but I would think it is just an assumption that neanderthals didn't have dogs. The first possible dog is 32k old from Altai, and Hss is not known to live there at the time, though Neanderthal and Denisovan were. Dogs apparently lived in caves with Homo Erectus in China over a hundred thousand years ago, and monkeys have been folmed "domesticating" puppies and indoctrinating them into their clans.

It is my no means clear that modern humans had domesticated the dog before Neanderthals were extinct or virtually extinct.

Meat, Processed Meat and Cancer Risk: Interview

gregladen — Fri, 06 Nov 2015 11:55:50 +0000

Meat, Processed Meat and Cancer Risk: Interview

A few days ago the UN agency in charge of keeping track of cancer risks listed meat and processed meats as to some degree or another likely to cause an increase in cancer risks. I wrote about that here. More recently. I was interviewed by Joshua Holland on the Politics and Reality Radio show about that story. Here is the interview for your listening pleasure:

gregladen Fri, 11/06/2015 - 06:55

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Micro-Evolution In Greenland: Inuit Diet, Weight, and Stature

gregladen — Fri, 18 Sep 2015 08:11:12 +0000

Micro-Evolution In Greenland: Inuit Diet, Weight, and Stature

There is a new paper in Science linking genetic variation in people living in Greenland with long term selection for managing a marine-oriented diet, affecting stature, weight, and probably, physiological processing of omega-3 polyunsaturated fatty acids (PUFAs).

The vast majority of the variation we seen in stature (height) among humans is not genetic. That is a fact hard to swallow by so many of us who were told in biology class that "height is a complex genetic trait with many genes affecting it." It also seems wrong because the classic examples of variation in stature, the Pygmies of Central Africa (short) and the Maasai of East Africa (tall) are assumed to be populations under selection that caused them to be outliers. Of course, the Maasai are really not that tall by modern Western standards, but the story about them being tall, first told by relatively short European travelers who met them in the 19th century, persists, despite the fact that those travelers' offspring, such as Modern Americans and Brits, are in many cases significantly taller than their own ancestors without natural selection being the cause.

But there are some genetic factors that control height and weight and account for some percentage of variation in those phenotypes. Pygmies taken from their homeland and raised among people with unlimited food supply do not grow tall. They may become obese, but not tall, because one of the main genes that regulates growth in almost all humans simply does not function in Pygmies. (One individual Efe Pygmy I've met who was raised among Italian nuns, in Italy, was short but rather wide.) There may be other short statured populations with a similar genetically determined stature. But as far as we can tell, something like 20% (and that is probably an overestimate) of variation in stature in living humans over the last century or so can be accounted for by genetic variation. The rest is a combination of diet and, I suspect, an epigenetic effect linked to maternal size and diet. When a population of relatively short people get unlimited food the next generation is taller. But then, the next generation is taller still. It is as though mothers won't give birth to maximally sized offspring, just somewhat larger offspring, who then give birth to somewhat larger offspring, so the part of the demographic transition where everyone gets taller happens over a few generations. This is a well documented but not very well explained phenomenon, and the explanation I suggest here is merely a hypothesis.

A new study in Science looks at the Inuit people, and some Europeans living in the same place they live, in this case Greenland, and finds a genetic component to Inuit stature and weight. There are also other differences having to do with processing elements of their relatively unusual diet.

The key result with respect to weight and height is shown in the graph at the top of the post. The letters (GG, GT, TT) are the alleles (T is the derived allele). Homozygotes for the derived allele are quite a bit less massive, and a small amount shorter, than those without the allele, and heterozygotes are in between.

Here is the abstract from the paper:

The indigenous people of Greenland, the Inuit, have lived for a long time in the extreme conditions of the Arctic, including low annual temperatures, and with a specialized diet rich in protein and fatty acids, particularly omega-3 polyunsaturated fatty acids (PUFAs). A scan of Inuit genomes for signatures of adaptation revealed signals at several loci, with the strongest signal located in a cluster of fatty acid desaturases that determine PUFA levels. The selected alleles are associated with multiple metabolic and anthropometric phenotypes and have large effect sizes for weight and height, with the effect on height replicated in Europeans. By analyzing membrane lipids, we found that the selected alleles modulate fatty acid composition, which may affect the regulation of growth hormones. Thus, the Inuit have genetic and physiological adaptations to a diet rich in PUFAs.

How long have the Inuit been living this lifeway, in this environment? Actually, not that long. The researchers, in their supplemental information, suggest that it could be as long as 30,000 years, but this is unlikely, or at least, the story is more complicated.

There are several complications to understanding the history of the selective environment of the Inuit, the environment that would have shaped this genetic adaptation. First, the environment has changed. Not only have we gone from an ice age to no ice age during this 30,000 year time period, but with sea level rise during the Holocene, the ecology of the arctic has changed considerably. Large areas of the continent have been inundated by the sea. Prior to that, most of the ocean adjoining land was immediately deep. With the inundation of the continent, vast relatively shallow areas of ocean would exist. Nutrients well up along the continental shelf, but shallow areas are also potentially nutrient rich because of sediments coming off shore. During glacial melt periods, there may have been frequent large scale fresh water incursions which would have had occasional disastrous effects on the local ecology. The position of estuarine settings, which can be very productive, would change. As sea level rise slowed, near shore sediments may have had a chance to build up, causing regional increases in productivity.

The migratory patterns, overall distribution, and abundance of marine mammals and common shoaling fish would have changed dramatically, and multiple times, during the last several thousand years. It would not have been until about five thousand years ago that things would have settled down allowing long term regional foraging adaptations to emerge. Prior to that there may have been periods when the marine environment was significantly more, or significantly less, productive.

Meanwhile, the ancestors of the Inuit themselves moved a great deal during this period. They were not in Greenland, or anywhere in North America, 30,000 years ago, but rather, in an unknown location in Asia. The Inuit ancestors were part of a later migration into the New World. The association (population wise) of true Arctic people and others living farther south is not known.

A second factor is cultural adaptation. When we look at the traditional Inuit foraging patterns and associated technology, together with the preceding prehistoric Thule adaptations, we can't help but to be impressed with the highly specialized effective approaches, both strategically and technologically, to acquiring marine resources. Boats, lamps, harpoons, and processing tools are highly refined and efficient. That material culture and strategic approach, however, is only a few thousand years old. Before that, in the region, were the Dorset, who simply lacked many of these tools. It is possible that the Thule and Inuit had sled and sled dogs, but earlier people in the Arctic did not. And so on. The ancestors of the Inuit, just a few thousand years ago, could not have had as specialized a diet as the traditional (modern ethnohistoric) Inuit. Cultural adaptations changing over time is as important as, if not more important than, the afore mentioned likely changes in environment.

So, I'm not going to argue that these adaptations are not 30,000 years in the making. Rather, I'll argue that strong selection for these alleles could be as recent a few thousand years or even less, and that prior selective environments (the combination of the natural environment and human cultural adaptations to it) may have different and the situation may have been rather complicated for many years. In other words, the new, and very interesting, results looking at the Inuit genome need to be integrated with a better understanding of Inuit history, which is probably going to require a lot more research in the region.

There is a second point I want to make about this paper. We see research suggesting a genetic explanation for a lot of things, but often, in the past, that has involved finding a correlation between this or that genetic variation and a presumed phenotypic feature. Often, the next key step to establish the link isn't, perhaps sometimes can't be, taken. This is the link between the observed genetic variation and a good physiological story. The present research finds genetic variation associated with physiological features that seem to be associated with a marine-oriented diet in an Arctic or Sub Arctic setting. That makes this research really valuable.

____________________________
Greenlandic Inuit show genetic signatures of diet and climate adaptation
Matteo Fumagalli, Ida Moltke, Niels Grarup, Fernando Racimo, Peter Bjerregaard, Marit E. Jørgensen, Thorfinn S. Korneliussen, Pascale Gerbault, Line Skotte, Allan Linneberg, Cramer Christensen, Ivan Brandslund, Torben Jørgensen, Emilia Huerta-Sánchez, Erik B. Schmidt, Oluf Pedersen, Torben Hansen, Anders Albrechtsen, and Rasmus Nielsen
Science 18 September 2015: 349 (6254), 1343-1347. [DOI:10.1126/science.aab2319]

gregladen Fri, 09/18/2015 - 04:11

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Did you ever wonder how you are going to die?

gregladen — Wed, 07 May 2014 11:37:58 +0000

Did you ever wonder how you are going to die?

I'm thinking it will be the food you eat that gets you. Here's why.

Humans eat a wide variety of foods; as a species, the diversity of species we eat is greater than any other animal by a very large margin, with the only quirky exception being the animals that we take along with us, the commensals such as rats and cockroaches. Most primates eat a high diversity of foods, but about two million years ago or a bit less, according to the “Cooking Hypothesis” (which a lot of people think is correct) we took an already diverse primate diet and added to it anything we might encounter in the environment that could be made edible with heat and added that to our diet. More recently, beginning about 10,000 years ago, we applied additional technology and the new practice of plant husbandry to convert other foods, some edible some not, into more useful items for our diet. Humans around the world did this independently over several thousand years, in parallel.

Then we got boats that were capable of doing magical things like sailing up wind, and navigation technologies that allowed humans to be less lost when doing so over great distances. Some humans had done this much earlier at a smaller scale, but by the 15th century there were big wooden boats criss crossing the seas, bringing people to places they had never been before, and along with them the foods people ate all over the world.

Have you looked at photographs of traditional people living in traditional, seemingly timeless, ways in places like Africa, the Amazon, or New Guinea? Look again, and focus on the things that form the backdrop for the scenes shown in those photographs. One of the things you’ll see in many pictures is the plantain, or the banana. You might notice the huge elephant ear leaves of taro plants. If you look closely you might notice cassava growing in the fields, or maize.

Maize was domesticated in Mexico, taro, plantains, and bananas in various different locations across south and southeast Asia. Cassava comes from the lowlands of South America, and potatoes come from the Andes. Some Yams come from Africa, some from South America (I oversimplify a bit). You can’t find a modern traditional diet, as it were, that does not include ingredients from continents other than where the traditional diet lives today, except perhaps in Ethiopia. Everybody eats everybody else’s food all the time. The main determinant of where food is grown is not where it was first domesticated, but rather, the limitations of seasons, rainfall, heat and cold. And even there, the limitations are relaxed. Maize only grows in the colder regions because varieties have been developed to do so, and many plants are grown in regions normally too arid for them, by virtue of irrigation.

Adding all this up – the diverse primate diet, the addition of cooked foods otherwise not edible, the artificially selected crops, and the global exchange of horticultural goods and practices – and you get a huge variety of food, the largest variety of food any species has ever managed to include in its diet. (Other than the rats and cockroaches, of course.)

Despite all this diversity, something has remained more or less the same all along. The “traditional” diet for humans, though much altered with cooking, is relatively low quality. I use the term “low quality” in the way an ecologist uses it. How many usable calories do you get out of a kilo of the food item under consideration? Or, related, how much work do you, using food preparation, chewing, and digestion (including the work done by the friendly microbes living in your gut) to convert that kilo of food into energy?

It is easy to see how our traditional diets are low quality by comparing them to the diets of a handful of primates that live almost entirely off of insects, or tree sap, or nectar. If we look at birds, we see the same thing; many species of birds eat pure sugar of one form or another. A few other animals have very high quality diets. Generally, carnivores have higher quality diets than herbivores. There are no carnivores that use multiple stomachs or habitually regurgitates and re-consume their animal prey in order to digest it. Herbivores that eat grass or leaves spend a lot of time feeding, have massive digestive systems designed by natural selection to digest the hell out of the food, and sometimes they have to “eat” the same food multiple times to get enough energy out of it to survive. Humans are somewhere in between. Some of our digestion is done pre-consumption by cooking and processing, but for the most part our natural, traditional diet takes a fair amount of work to process. We don’t live off of sugar water like hummingbirds and many insects do.

And this is why the leading cause of death in the United States and some other countries has shifted from the usual panoply of causes – infectious disease, accident, homicide, etc. – to our diets. Our diet is the most likely thing to kill us, and lately, the primary mediating factor in this particular cause of death is obesity and/or diabetes.

The “traditional” diet of any group of people, as I’ve already outlined, is relatively recent historically, being the result of 10,000 years of developing plants and a few hundred years of transferring crops and growing methods across the world. That traditional diet was prominent globally through the 19th century and well into the 20th century. The food came from farms, and although many amazing novel technologies were being applied on those farms, such as better plows and various other things that could be drawn behind oxen, a team of ponies or horses, or a small tractor, those technologies did not change the diets too much.

But as technologies developed, farms began to scale up. This is the reason that the New England countryside is graced with young forests criss-crossed with quaint stone walls. Those stone walls were field boundaries in the old days. But as farming scaled up, it became economically inviable to have small fields on small farms. A few other things went wrong on some of these New England farms as well, including some climate glitches and some other economic effects that drove farmers off the land and in some cases into cities where there were jobs working in mills. But some of those farmers took part in the great Westward Migrations, as the country grew, and established a new kind of agriculture in the vast regions of the midwest and plaines.

Add a growing urban market for foods, government help in the form of extension and agricultural colleges, more technology such as combines, railroads to move produce to market, mills to process the produce, add some water (irrigation) as needed and salt to taste. It took decades, but we went from an agrarian economy where the same traditional diet we had been eating was produced on a somewhat larger scale, to an agricultural economy that produces mostly one single thing. This product:

OK, I’m exaggerating there. It isn’t really true that the entire US agricultural system has been converted over to the production of sugary drinks. But sometimes it seems that way. Vast expanses of corn are grown in the midwest and plains, and that corn is used to produce vast amounts of ethanol (as fuel), alcoholic beverages, sugary substances including cola, feed for animals, and some of it even makes it to the table as … well, corn. But lets step back to the original comparison of “traditional diet” and the diet many Americans eat today.

When you eat a traditional meal, a good amount of that food is low quality, relatively hard to digest, carbohydrates with a mix of proteins. There will be a little simple sugar here and there and a bit of fat here and there.

The simple sugars go right away to the liver, where they supplement the body’s immediate energy stores. The complex sugars, the carbohydrates that consist of much larger and more involved molecules, take time to digest and break down to eventually use as fuel. So the sugar gives you a small amount of immediate energy and the complex carbohydrates give you energy over the coming hours.

The fats are simply stored up. If you eat fat, the fat molecules are minimally processed, moved to your hips or wherever, and are pasted there for later use. Or, forever, depending.

When you eat a modern diet, it will have two major difference from the traditional diet. The foods at the two ends of that spectrum of availability will be in greater proportion. Instead of having a bunch of low quality food in the middle, with a little fat (for later) on one end of the spectrum, and a little simple sugar (for immediate use) on the other end of the spectrum, the modern diet will have piles of fat and piles of simple sugar and not much in between.

So, what happens? The fat goes where fat goes, as stated already, but there is more of it. The sugar overloads the liver, which detecting an overabundance of energy, converts the sugar to some form of storage, and some of that is fat that joins up with the other fat. There is also a kind of molecule the liver converts some of that sugar into, stored in your liver, for in case you get hungry between meals. That molecule reduces the chance your body will use any of that stored up fat as energy.

Two thousand traditional calories provides you with energy for now, energy for the next several hours, and a bit of energy for much later. Two thousand modern calories provides you with way more energy than you need for now, and a huge amount of fat that you’ll never use because you are never going to let much time go between meals. Because there is a fast food joint just down the street. And your refrigerator and cabinets are full of junk food.

And that’s not all. Our system of agriculture has all sorts of other negatives as well. The following is from the Food and Agriculture page of the Union of Concerned Scientists:

Food and Agriculture: Toward Healthy Food and Farms
Our agricultural system has lost its way.

Millions of acres of corn, soybeans, and other commodity crops, grown with the help of heavy government subsidies, dominate our rural landscapes.

To grow these crops, industrial farms use massive amounts of synthetic fertilizers, herbicides and pesticides, which deplete our soil and pollute our air and water.

Much of this harvest will end up as biofuels and other industrial products—and most of the rest will be used in CAFOs (confined animal feeding operations) or in heavily processed junk foods, which seem cheap only because their hidden costs don’t show up at the cash register.

Industrial agriculture is unhealthy — for our environment, our climate, our bodies, and our rural economies.

A Better Way: Sustainable Agriculture

There’s a better way to grow our food. Working with nature instead of against it, sustainable agriculture uses 21st-century techniques and technologies to implement time-tested ideas such as crop rotation, integrated plant/animal systems, and organic soil amendments.

Sustainable agriculture is less damaging to the environment than industrial agriculture, and produces a richer, more diverse mix of foods. It’s productive enough to feed the world, and efficient enough to succeed in the marketplace—but current U.S. agricultural policy stacks the deck in favor of industrial food production.

… and there is much much more than that, visit the page.

Yesterday, I went to a symposium hosted at the Humphrey Institute at the University of Minnesota and organized by the Center for Science and Democracy at the Union of Concerned Scientists. A description of the symposium is here and the entire thing was “taped” and will be available. I’m not going to tell you anything major about the symposium now; I’ll wait until the video is available, then I’ll provide you with my thoughts on it. For now I’ll just say it was quite good, eye-opening, and that you’ll definitely want to watch it. In fact, you should feel a little bad that you weren’t there.

Stay Tuned.

gregladen Wed, 05/07/2014 - 07:37

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Evolution of Diet

Origin of Agriculture

Now compunding the above problem is http://www.theguardian.com/environment/2014/may/07/climate-change-food-… rising CO2 levels are reducing the nutrient value of the foods we do grow.

This is really interesting. Any thoughts on how this could counter our enormous effort to destroy the planet?

I think that this was not up to par. Do you claim that 2000 calories of one food promotes more weight gain/fat accumulation than 2000 calories of some other food? Really?

Please see if you can find any *closed ward* studies supporting that premise.

Ole

Yes, essentially. 1000 calories of fat will give you fat. 1000 calories of non-fat complex carbohydrates might do a good job of giving you hours of energy as it is digested, and chances are some of it won't be digested into usable energy. 1000 calories of simple sugar, all at once, is too much too fast to use as energy so some will be converted to stored energy, and depending on what the liver already has stored up, some/much of that will be converted into fat.

It simply isn't the case that 1000 calories is 1000 calories. It depends on what form it comes in and the rate of ingestion.

This is not controversial or even particularly new.

See this, a writeup of the event with the video: http://scienceblogs.com/gregladen/2014/05/21/forum-science-democracy-an…

Catching Fire. The other one.

gregladen — Sun, 24 Nov 2013 09:23:00 +0000

Catching Fire. The other one.

Catching Fire is apparently a very popular book and/or movie that everyone is very excited about. But Catching Fire: How Cooking Made Us Human is a different a book about some interesting research I was involved in about the origin of our genus, Homo.

You can pick up a copy of our paper on this page. We call it "The Cooking Hypothesis." The basic idea can be summarized with these points:

1) Cooking food transformed human ecology. Many potential foods in the environment can't be consumed by humans (or apes in general) without cooking. But adding cooking to our species-specific technology, we can access those foods effectively transforming our ecology to a much greater extent than the vast majority of evolutionary transitions, especially single-event transitions, have ever done. The total number of calories in the natural environment that become available to an ape that can cook goes up by orders of magnitude.

2) This increase in available calories left a biological signal that is very impressive. Two major changes happened in the hominid body (in early Homo erecuts/ergaster). One is an approximate doubling in body size from an earlier Australopithecine or "Early Homo" ancestor. The other is a reduction in tooth size. Less eating equipment with a body demanding so much more in energy to grow and maintain signals a fundamental change in the food supply. There may be more than one way this could have happened, but so far adding cooking to our technology seems to be the best explanation.

3) Related, this is when we see brain size, relative to body size and in absolute terms, increase. Neural tissue is picky, expensive, and costly. Having a significant increase in brain size may be related to the demands (on the brain) of adding cooking to our behavior in that the size increase is allowed by the extra energy. And, it may be related in that the larger brain may provide the capacity to have this behavior.

4) The actual act of cooking, as a technology, may or may not demand a larger brain. But the process of cooking almost certainly involves central place foraging (bringing all the food back to one place, much of the time, to cook it) and delayed consumption (as opposed to eating the food where you find it). The basic pattern for a chimpanzee-like ancestor is to eat the food where you find it. Bringing food into close proximity to other members of your group virtually guarantees direct competition for food, which makes getting to food to begin with a highly questionable thing to do. In order for cooking to work, the social interactions typical of an ape have to be modified significantly. Cooking demanded, facilitated, and made major changes in social structure "worth it" from the point of view of natural selection.

5) These changes in social structure are probably indicated as well by changes in stone tool technology. Early cookers also were early hand-ax makers, for example. Human ancestors went from making primarily expedient, one time use, very simple stone tools to making tools that required a great deal of investment in time and energy to learn the technology, get good at it, and even for the production of individual tools (including acquisition of better than average raw materials in many cases). Once the tools were made they seem to have been used, often, for long periods of time. It is hard to imagine a chimp-like creature carrying around a tool into which she invested time and energy without it being taken away. This is an important transformation.

6) Less visible but very likely is a change in social system which could be called the rise of proto marriage. Sexual arrangements of a human-like kind are very different than for chimp. The ability to allow others to possess food or invest in more sophisticated technologies may be parallel to the ability to have more or less exclusive sexual contracts among individuals. This is indicated independently in the fossil record by a large decrease in sexual dimorphism in body size. In polygynous species like chimps males are often much larger than females, and this seems to have been the case with pre-Homo erectus/ergaster ancestors. But at the same time the body size increase and tooth size decrease happen, we also see a reduction in sexual dimorphism in body size, strongly indicating a major change in social arrangements. The best two explanations for this may be a shift to a gibbon-like pattern of paired-off monogamous adults living more or less alone, or a human-like pattern of paired-off monogamous adults living in larger social groups.

It is an idea that would have caught on. It would have selected for more nuanced communication, and may thus have facilitated the origin of what we now know of as human language and symbolic processing.

So when you are eating your Thanksgiving dinner this year, most of which will be cooked, look around at the people at the table and, briefly, imagine them to be chimps. Then go back to your meal and try to put all those thoughts aside...

gregladen Sun, 11/24/2013 - 04:23

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I read and recommended the book several years ago. Since then a bout of oral cancer , loss of dentition due to radiation therapy, and a years-long regime of liquids have led to even more appreciation of diet technology. Ownership of a Vita-mix is a far cry from the needs of my ancient ancestors. Of course by now, at 71, I've already lived to an age that would have been unthinkable millennia ago, but that has not diminished my appreciation and gratitude for the creativity of the Old Ones.

Greg, Lars Werdelin has an article in the latest Scientific American about the timing of large carnivore extinction in Africa (actually, more precisely, a pronounced and permanent drop in species diversity) and the apparent adoption of hunting by hominids. Does this fit with the proposed timing of the advent of cooking?

The total number of calories in the natural environment that become available to an ape that can cook goes up by orders of magnitude.

Miscellaneous tangents:

* "Cooking" when first invented involved either dropping something into fire/coals or skewering it with a stick to pass it over/through flames, no? Works great for bigger pieces of meat, not so much for gathered seeds, leaves, roots, grubs, eggs, small animals...

* Cooking-quality pottery must have taken generations of acute r&d frustration. The payoff to a gathering economy from being able to make a soup of readily scrounged edibles must have been revolutionary.

* Anywhere with a lot of tubers, the baked-in-mud technique would likely be discovered not long after the invention of campfires. No doubt Africa has at least its share of tubers, but that benefit could only occur after fire-using was established.

* How much advantage would keeping a nice bright fire going at night add up to in terms of predation prevention? Or a nice smoky fire as insect deterrent?

* How much benefit came from cooking as a calorie catalyst as compared to parasite prevention?

* Field observations suggest tendencies to gather around and stare at fires has been strongly selected for during multiple generations of Homo (semi)sapiens.

I didn't mention it in this post but we postulated based on earlier work that tubers and roots etc would be among the first things cooked. Seeds, eggs, etc. don't need to be cooked. Small animals are easily cooked on a fire with no extra instruments.. I've eaten plenty of small rodents, song birds, and bats cooked that way.

(On the same page I pointed to you can see research on tubers that relates.)

Fires don't scare away predators in my experience. At all. Archaeologists have long suggested that this is a role of fire but this is wishful thinking. As a calorie catalist fire has potential (see the Wrangham et all paper).

Lars: I'll have to look at that timing.

Cooking also kills bacteria and other food-borne infectious agents and parasites. Disposal of food wastes in fire, such as by throwing the inedible (to humans) parts of food plants and animals into a fire, also renders them unsuitable for use by flies and rodents.

These factors would have produced changes in disease and mortality patterns over time. Are there any archaeological data on that?

It also occurs to me that the advent of fire would have led to the at-first accidental burning of plants that happened to be poisonous or psychoactive. This would have had to produce the impression that an "unseen force" was striking people dead, making them sick, or giving them visions: an unseen force entirely different to that unleashed by eating the respective plants.

The question is, would early humans have attributed the new "unseen force" primarily to the fire, the smoke, or the plants? And how would that have affected the development of "religious" beliefs early in human history? (Even to this day, the use of incense in churches can be considered a faint echo of the idea that there is a connection between smoke and the deity or spiritual realm.)

Interesting. If purposefully made fire use was a feature of H. ercectus or ergaster, that means that H. sapiens may have been literally eating cooked food for as long as we were a species. So much for the claims of raw food enthusiasts that we were evolutionary adapted to eating raw food (not that I put much stock in those types of arguments in the first place).

Also, regarding your (Greg H) comment that fire does not deter predators: since it seems to be an article of faith (or at least a scientific "urban legend") that it does, how do you think this belief has persisted so long?

BTW, when you wrote you've eaten "bats" cooked on a fire I almost read that as "brats," and thought "big deal." ;-D

Nick

edit: re: "(Greg H)" Gah! I meant Greg L of course. We need an edit button

Nick: Yes, exactly.

How has the belief of fire working on predators persisted? It is one of those made up things, made up by arm chair theorists, who never tested it! I assumed it was likely true until the first time I tried to scare off a predator with fire, and that was the first of a series of failed attempts to do to.

Predators probably avoid human hunters because the penalty of harassing them is severe and extend to kin. But fire per say is only a signal that there may be something to eat.

I wonder if this something else we can blame on Kipling.

@Pierce Butler: I've cooked all kinds of veggies on sticks over a fire. My friends and I do "everything on a stick" parties, where we build a fire and cook wildly creative food on sticks. The bacon rolls are a particular hit, although I don't think Neanderthals had those. And the whole quail were easy and delicious.

Cooking roots in coals is easy and works great, especially if you wrap them first (aluminum foil or large green leaves). Eggs can be cooked either over the fire with tongs (fast, but there's some risk of explosion) or placed in a mildly hot spot near the coals for an hour or so.

Probably the best thing I've tasted from a campfire was the whole chicken, wrapped up and buried in coals under the fire, like they do with pigs in the South Pacific.

Cooking food together is about as human as you can get, and I think it's pretty unlikely our fully human ancestors ever lived any other way.

The Efe Pygmies typically cook using pots that are either traditional clay ones they are theoretically able to make or, more commonly, cheap aluminum trade pots that are used in the region.

One day I asked a group I was living with if they could cook without the pots. I expected them to say yes, but to do things like those suggested here, using sticks for certain things, or putting objects on the coals, etc. Also, I expected them to limit the range of things they would be willing to cook this way.

What happened was instead quite shocking and turned out to be an example of how limited we are in making guesses as to what is possible or not possible, or even difficult vs. easy.

They told me that occasionally they needed to cook without pots, so they had a way to do this.

They made rice, beans, and cooked some meat. They did it all just as you would do it with pots, but they made "pots" out of leaves. It wall went very well and they made it look easy.

I think there is a typo in #6:
"...at the same time the body size increase and tooth size increase happen". Shouln't that be 'tooth size decrease"?

Fascinating hypothesis. Are there implications in this view for possibly finding earlier direct evidence of fire use so early - 1.8 MYA is a lot earlier than the current evidence, isn't it?

Good catch, thanks.

As for the earliest evidence of fire, we are arguing that the body size increase IS a biological signal for that, but I know that is indirect.

The earliest evidence for fire is the burned patches at East Turkana at 1.5 mya. Not every one accepts that, but on the other hand, many who reject that evidence accept Zhoukoudian at 0.6 mya even though we think that is guano burning naturally. But since it is a later date and longer in the literature it is somehow less uncomfortable calling burning sloth shit human hominid controlled fire than patches that look like fire hearths and have magnetic properties consistent with controlled fire direct evidence.

There is also evidence in South Africa over a million.

Just a quick note in response to the commonly made misstatement way up in comment #1 that
Of course by now, at 71, I’ve already lived to an age that would have been unthinkable millennia ago
70-80 was the typical life expectancy (if you survived childhood) three thousand years ago. This is clearly stated in Psalms 90:10 (a historical note, not a supernatural one).
--bks

http://scienceblogs.com/gregladen/2011/05/01/falsehood-if-this-was-the-…

Fires don’t scare away predators in my experience.

A former national park warden in South Africa/Southwest Africa (as it was then) told me that one evening he returned to the camp fire he'd left blazing to deter predators, only to find it surrounded by 5 lions basking in the warmth. A Namibian colleague related that, as a student, one evening she stayed alone at a campsite. A rhino dashed in from the dark then stamped around, dispersing and putting out the fire before leaving.

Apart from using metal or earthenware cooking pots, mopani worms (caterpillars) are cooking by dropping them in glowing embers. It seems the ash also has a preservative function. I've read that in some societies, food is cooked by dropping fire-heated rocks into gourds containing water (and the food).

@Greg #14:
Thank you for those extra data points.
I'll get the book and start following the paths on that fire controlling evidence. I agree that there should be a good (very good) reason or reasons for these roughly contemporary phenontypical shifts in body size, tooth shrinking, and brain growth, etc. That there _is_ >1MYA evidence albeit not fully recognized is great to know. Now to search it out!

Richard: Your comment came through just as I was about to give a lecture on early fire and I worked in your examples.

The idea that Rhinos stomp out fires is a meme I've heard before, and it is part of "The Gods Must Be Crazy" ... still not sure if I believe it but I've heard stranger things (in South Africa!)

Greg: I mentioned 'The Gods Must Be Crazy' to the colleague who told me about the rhino stamping out the fire - she had not seen the film and I don't think she was one to exaggerate, so I'm inclined to believe her.

What about the idea that cooking food pre-digests it so that energy used for the gut is made available for the brain?

Meat'ing future food demands

gregladen — Wed, 30 Oct 2013 09:34:21 +0000

Meat'ing future food demands

My friend and colleague Emily Cassidy gave this TED talk! Her research is some of the most important work being done. Have a look:

gregladen Wed, 10/30/2013 - 05:34

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Emily Cassidy

Food supply

Norman Borlaug knew that his solutions - higher yielding crops and use of chemical fertilizers and herbicides - was only a temporary solution.

Emily Cassidy gave a good talk: well researched and positive. However she should have focussed more on options for population control. The empowerment of women - especially given them control over their own fertility - is of vital importance.

Going vegetarian or even reducing meat consumption is just a temporary fix. Unless humans make conscious decisions to curtail population growth, human numbers will continue to expand to the limits of food supply - until every single calorie captured by the entire planetary ecosystem is consumed by humans, and the world's ecosystem is simply converted into a vast machine to feed the humans. We are halfway there already. Let's not go any further.

Chicken and pork production on a commercial scale is today one of the most repulsive and inhumane forms of factory farming. Do we really want to increase the scale of this misery?

Beyond this, there also lies the questionable future sustainability of the petroleum based systems of food production currently dominant in the industrial world. The late Dr.Albert Bartlett used to give a lecture on these issues, which I recommend to anyone whose interest has been sparked by Emily Cassidy's talk: http://www.youtube.com/watch?v=umFnrvcS6AQ

Good point about the population, but Emily's expertise is in the agricultural system, so that's why she focused on that.

Inherently, swine production is more productive than cattle production, so I can imagine that if more humane ways were applied in both cases, the pork production would still be much higher. (Humane up to the point where you kill and eat them, that is.)

Perhaps I missed it as I'm at work but I did not hear her deal with the use of wasted food. Using "slop" to feed pigs would take calories/protein she is already attributing to human used food and reuse it in meat production - that could seriously change her 10% ratio if the practice were wide spread. The amount of food that is wasted in first world countries is incredible and could go a long way in producing meat - particularly vegetable crop waste (ever look in a supermarket's dumpster?).

Perhaps Emily will chime in here, but I think the 10% doesn't change with waste, but waste is on top of it. (She does briefly mention waste).

Pigs are more efficient producers of meat than cattle because of their life history parameters, but since you can feed them a wider range of things (including slop) that probably makes a difference as well.

Just say Vat Meat. At present we can barely produce artificial meat, but this is considered a problem that can be solved. It will address both the food resource issue and the animal cruelty issue at the same time. Though of course, there is no substitute for family planning and bringing our population down to a sustainable level. This is not an either/or, but an and/both: we need more efficient food production & distribution, and fewer mouths to feed.

Doug Alder,

You are right, feeding food waste to swine would be a great benefit to the efficiency of converting plant stuff to meat. However, many countries have policies against such practices. Many worry about the sanitation of feeding waste to pigs.
Incorporating food waste back into a usable feedstock is something that we should put more investment in, in my opinion.

At one time my daughter worked for a company which made licorice candy. They would make a batch of one flavor, immediately followed by a batch of another. There would be some mixed up product produced in the transition. This was routinely sold to a local pig farmer for pig food.

I recall reading that pigs grow much better on military slop than on civilian slop.

Some years ago, and ecologist, maybe Sokol, did some calculation and concluded the most effective way to slow human population growth was to lengthen generation time; for women to have their first child at an older age.

This is the foundation for the empower women solution, I think. Also providing good healthcare and nutrition for pregnant women and young children cuts down the perceived need to have more children.

Emily Cassidy,

I was reminded of an article I ran across a couple of weeks ago regarding a new fad - table to farm to table - http://life.nationalpost.com/2013/09/17/haute-fowl-chickens-exclusively… - not at all solution to the problem I know but the genesis of my previous comment :)

Greg,

Why isn't the contribution of seafood mentioned? Is it so meager a portion of the world's diet as to not be worth mentioning?

Getting people to give up calorie dense food like cheeseburgers is not as easy as it sounds. Ask you primary care doctor how many obese patients she sees and how many have radically changed their diet.

R.I.

I believe seafood is not mentioned because Emily's work is on agriculture and comparing those systems, and the data set does not include seafood.

New link between exercise and weight loss uncovered?

gregladen — Fri, 27 Aug 2010 12:36:58 +0000

New link between exercise and weight loss uncovered?

A recent paper provides the groundwork to establish a way for exercise to diminish appetite. Or, more likely, for sedentary behavior to increase appetite.

It is well known that exercise burns calories. Personally, I think that's overrated: Strength building raises your metabolic demand, and THAT burns calories. But that is not the main topic at hand. New research indicates that exercise also increases the sensitivity of neurons that are related to the control of the feeling of satiation. Therefore, you feel full rather than hungry sooner and/or more often.

In rodents. So far.

The research team made obese rodents exercise was found to increase the amount of IL-6 and IL-10 protein levels in the hypothalamus, which in turn changed the threshold for the feedback system that ultimately releases insulin and leptin, which are the magic juices that seem to affect hunger and related system. Indeed, leptin has been seen for some time as a key to understanding weight control, has been implicated in various concepts like the "set point" and is linked to numerous rather complex systems. What may be happening here is that insulin and leptin levels act one way in the sedentary person and a slightly different way in the active person.

I'm going the gym.

Oh, wait, OK, I'll finish this blog post first.

Here's what the authors say about the study:

The hypothalamus is a brain region that gathers information on the body's nutritional status and governs the release of multiple metabolic signaling molecules such as insulin and leptin to maintain homeostasis. Overeating and obesity are associated with insulin and leptin resistance in the hypothalamus, and recent studies provide an intriguing link between inflammation and dysfunction of hypothalamic insulin and leptin signaling through activation of IKKÎ², a key player in immune response, and endoplasmic reticulum (ER) stress. This means that strategies to reduce the aberrant activation of inflammatory signaling in the hypothalamus are of great interest to improve the central insulin and leptin action and prevent or treat related metabolic diseases. Using a combination of pharmacological, genetic, and physiological approaches, our study indicates that physical activity reorganizes the set point of nutritional balance through anti-inflammatory signaling mediated by interleukin (IL)-6 and IL-10 in the hypothalamus of rodents. Hence, IL-6 and IL-10 are important physiological contributors to the central insulin and leptin action mediated by exercise, linking it to hypothalamic ER stress and inflammation.

And, if you want to know a LOT more about this process, click here to download a PDF primer on Exercise and Hypothalamic ER Stress.

You can read the paper, published in PLoS Biology, here.

Ropelle, E., Flores, M., Cintra, D., Rocha, G., Pauli, J., Morari, J., de Souza, C., Moraes, J., Prada, P., Guadagnini, D., Marin, R., Oliveira, A., Augusto, T., Carvalho, H., Velloso, L., Saad, M., & Carvalheira, J. (2010). IL-6 and IL-10 Anti-Inflammatory Activity Links Exercise to Hypothalamic Insulin and Leptin Sensitivity through IKKÎ² and ER Stress Inhibition PLoS Biology, 8 (8) DOI: 10.1371/journal.pbio.1000465

gregladen Fri, 08/27/2010 - 08:36

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Nice review. I agree for the most part with this:

"It is well known that exercise burns calories. Personally, I think that's overrated: Strength building raises your metabolic demand, and THAT burns calories."

Most people are considered regular exercisers if they follow the old-school recommendation of 20 minutes a day, three times a week. Go to the Runner's World forums and you'll find that the average participant puts in maybe 15 to 20 miles a week, meaning that he burns about 200 to 300 more calories than he would if sedentary. That's really not much--people like the simpistic approach of saying "That's a loss of one pound every two to two and a half weeks," but in practice a lot of people who have begun exercising consciously allow themselves to eat more, offsetting the potential shedding of poundage.

At my peak I was burning a pound's worth of calories every couple of days (in one calendar year, I averaged 103 miles a week of running), so my situation was different. However, I was never in it for the weight loss. The reality is that for most people diet makes a far greater contribution to weight than does exercise (and I'll omit genetics from the discussion as some like to think it makes no difference).

kemibe, I'm skeptical of your analysis. Maybe the exercise of running alone only burns 200-300 more calories than being sedentary, but what about the additional calories burned from gain in muscle mass? Since I started running 8 months ago (~20 miles a week), my quadriceps have become noticeably larger, which I would guess has resulted in the loss of many more calories while sedentary today, than I would have lost 8 months ago.

I had to cut 3 new notches in my belt over the course of 6 months, and I still eat to satiation.

I am not sure that you two are disagreeing here. On one hand, added activity does not burn off fat at any kind of impressive rate unless you keep your caloric intake low enough that you are dipping into fat reserves often, and/or biking the Tour de France.

On the other hand, whatever activity you do, including sitting there watching TV, will burn energy at a rate proportionate to your muscle mass, so adding muscle mass will give results perhaps better than a longer run, depending.

This leads us to this: If you are going to spend X minutes a day working out, should it be pumping iron to get those quads (and glutes... they're bigger, so they burn even more) larger or do you spend it highly active ("aerobic") to burn off calories?

Answer: Some well designed plan that involves both. Get the muscle mass up fast and use it heavily.

I'd like to know this: What about swimming? The physical exercise is good, but it seems to me that being in a 70 degree pool will burn off a lot of calories just staying warm.

""It is well known that exercise burns calories. Personally, I think that's overrated: Strength building raises your metabolic demand"
Yeah..
But mostly because exercizing muscles use energy; if exercize didn't burn calories there would be no need to increase metabolic rate with strenght building.
So that's not overrated at all!
Best stick to archeology & anthropology..

Nah, Greg's right. Any well-designed weight loss plan will use strength and endurance training both; but of the two modes of exercise the more important component is diet - all the exercise in the world won't make a single bit of difference without actually controlling energy intake. It's fully possible to run a couple 10K's a week and not lose a single gram due to overindulgence in Gatorade or corn chips.

'course, when comparing the effect of diet and exercise it's also important to note that endurance exercise is generally a trivial component of any effective weight loss plan; the important bit is getting your strength training in. Adding endurance exercise to a strength-training plan will enhance results, omitting strength training will worsen them. The key component then, is diet and strength training with endurance exercise done on an "as time allows" basis.

A better diet without exercise is useless.

SamN:

...but what about the additional calories burned from gain in muscle mass? Since I started running 8 months ago (~20 miles a week), my quadriceps have become noticeably larger, which I would guess has resulted in the loss of many more calories while sedentary today, than I would have lost 8 months ago.

This is probably an optical illusion. Running will add muscle only for the severely sarcopenic. Muscle is gained only from high-load low rep exercises to near exhaustion, and running is a low-load high-rep exercise. Increase in muscle mass comes from building more myofibrils [actin, myosin, troponin, tropomyosin mostly] Endurance exercise builds mitochondria which take up only asmall amount of the muscles' mass.
What you are seeing is your muscles showing more definition because you have lost subcutaneous fat. The fact that you had to cut new holes in your belt confirms this - you have lost much of your pinchable fat under the skin and the fat around your internal organs [the bad stuff].
Energetically, running, biking etc burns far more calories per minute during the exercise than strength training. Strength training builds more muscle to expend more energy at rest.

Greg:

What about swimming? The physical exercise is good, but it seems to me that being in a 70 degree pool will burn off a lot of calories just staying warm.

First of all, very few pools are kept anywhere near 70 degrees. You can find lots of lakes at that temperature, but that's just too cold for most water activities for any length of time. Most pools are kept in around 78-84 degrees. Competitive training can be done in slightly cooler water. 84 feels slightly cool, 78 feels cold when you first get in.

And swimming is a good exercise for cardiovascular conditioning, but there have been some suggestions that exercise in water may not have the same salutary effects as an equivalent amount of dry land exercise. It may have to do with the coolness of the water keeping the core temperature down which somehow changes the release of appetite controlling hypothalamic hormones. There has been little or no experimental results to back this up, but it hasn't been rigorously studied AFAIK.

...added activity does not burn off fat at any kind of impressive rate unless you keep your caloric intake low enough that you are dipping into fat reserves often ...

All exercise will cause you to dip into your fat reserves, although high intensity-short duration will utilize fat only during recovery. The longer you exercise, the greater the proportion of fat will be used to support the activity as your muscle glycogen stores wane. [i.e. 35% @ 15 min; 60% @ 60 min; 80% @120 min at the same speed]

I find cycling is the best all rounder .especially for toning the bottom and legs . also when i had a back injury sometime ago my physiotherapist encouraged me to begin cycling once the acute phase was over .I was back to normal soon after

It may have to do with the coolness of the water keeping the core temperature down which somehow changes the release of appetite controlling hypothalamic hormones. There has been little or no experimental results to back this up, but it hasn't been rigorously studied AFAIK.

I'm sure this has already been worked into the Aquatic Ape Theory, but just in case, I may send Elaine a memo...

Hey great post Greg! I especially liked the quote "I think that's (exercise) overrated: Strength building raises your metabolic demand, and THAT burns calories." ... Well written post with some great info put forth in a straightforward manner. Now I know why long sessions on the treadmill were not giving any results! LOL..

Hey Greg
Awsome post i'd like to read more about this but the link in:
You can read the paper, published in PLoS Biology, here. redirects me to a "404 not found" any chance you would check that out?

Thanks

"The best exercise is the one you'll do."
- Covert Bailey

It doesn't matter what form exercise comes in, even if it's the single most efficient way to burn off fat and get fit. If you hate doing it, you won't do it. The key is to find something you like, something fun.

As for eating more when unhealthy less when exercising, it could also be a product of emotion, not just chemical. Depression has a known link to overeating, and when someone is unhealthy, it causes the person to eat more. When someone becomes fit, the person eats healthier and eats less.

http://www.medicinenet.com/emotional_eating/article.htm

It's only anecdotal, but I can testify to that effect in the past year when I decided to make a serious effort at improving my fitness level and losing weight. A year ago and eight kilograms heavier, I ate a lot - not so much junk food, but constant eating. Now that I'm fit, I snack mostly on oranges and apples and drink water instead of packaged "beverages".

I find that when I exercise, I don't get so hungry and I tend to want the healthier foods.
I think moderation in everything is key and we should just change to healthy diets and take some form of exercise a few times a week.

Nice one!

Nyamulagira Volcano and Human Evolution

gregladen — Mon, 04 Jan 2010 14:40:54 +0000

Nyamulagira Volcano and Human Evolution

I had mentioned earlier that the volcanoes of the Virugna region in the Western Rift Valley (as well as other highland spots) have often been islands of rain forest separated from each other by different habitats, including grasslands and wooded savannas. this has produced an island effect that has been a laboratory for evolution, and it is likely that these forest islands (and others in the greater region of east Central Africa and western East Africa) have been the loci of evolution of many endemic species. (See Island Africa: The Evolution of Africa's Rare Animals and Plants by Kingdon for an excellent overview of the Island Effect in highland regions of Central and East Africa.)

It is probably not a coincidence that two of the three subspecies of gorilla live within sight of each other (and of the main subspecies, the lowland gorilla) within this region. The Virunga volcanoes are not old enough to have supported island forests for the evolution of these specific subspecies, but other highlands in the region, or other volcanoes (perhaps in the Eastern Rift) may well have been the location in which they evolved.

And, as it turns out, there is reason to believe that the split between chimps and humans occurred on one of these volcanic mountain tops several million years ago. Or, at least, in an environment geologically similar to the upper reaches of the Virunga Volcanoes. But to tell this story right, I have to go back a few years.

... distant in the background African sounding drum music, distant thunder, polyphonic singing fades to the sound of steel on rock as dozens of workers are excavating elephant bones in the dusty windswept African plain under the watchful eyes of the Rwenzori ...

The Congo. Parc National de Virunga, well north of the Virunga Volcanoes, north of Lake ex-Edward. I was with a fairly large expedition. At the time we had been waiting for crucial supplies, including tents and cots and other accouterments of field life, to arrive in a truck the expedition had purchased in Kinshasa, which was being driven to the field site via the Central African Republic (there are no roads that traverse the Congo). The truck was several weeks late. So, on the occasion that we heard a vehicle on the nearby park road (once or twice a week), we had taken to chanting the name of the driver of the truck (Leo) while facing a mock-up of the truck made by a local school kid, that we had placed in a makeshift shrine under a tree near our dining area.

"Leo... Leo.... Leeeeoooooo...." we were chanting one day, in observance of our cargo cult, as we heard a vehicle driving down the road, well out of sight to the east.

When the sound of the vehicle suddenly shifted, with gears lowering, near the juncture of the main park road and the side road leading down to our research site, we didn't think much of it. The large muddy puddle at that spot caused all vehicles to down shift and slow. But this time, the vehicle in question stayed in low gear and we could hear it getting slowly closer to us... this truck had turned in to the research camp road! It was Leo! Leo had arrived with the tents and cots and the garlic and the other stuff!

But when the vehicle finally came in sight after traversing the 3 kilometer path that lead to our camp, we were very disappointed to see that it was not The Truck driven by Leo with Our Stuff. Rather, it was someone we did not know in a Land Rover.

Visitors.

The visitors turned out to be a chimpanzee conservation specialist on contract with the United Nations and her driver. She was on her way south to the Virunga Volcanoes to habituate the chimpanzees in one of the mountain top forest patches to tourism. That is similar to habituating the chimpanzees to researchers, but instead of wearing khaki's and carrying around notebooks ... so the chimps get used to that ... you wear loud print Hawaiian shirts with cheap cameras hanging around your neck and carry tour books and gin and tonics. So the chimps get used to that. I assume.

Anyway, the chimp conservation specialist eventualy moved on and went to the Virungas. I eventually (several months later) moved on and went to Cambridge Massachusetts, where I lived at the time (plus or minus) when I was not in the Congo.

And my first night in Cambridge had me crashing at the home of Irv DeVore, my advisor, the famous primatologist and forager researcher. Also crashing at DeVore's was Richard Wrangham, famous primatologist who at the time was being courted by Harvard, and was thus visiting from Michigan.

Richard and I had a conversation. It turns out that he had met up with the UN chimpologist in the Virungas at some point when I was at the other end of the park (this park is big ... traversing it the long way is not normally done, but when it is it can take a couple of days and you quite seriously risk your life). This led to an interesting conversation.

Richard and I started to exchange information and ideas. I had been looking at the use of roots by foragers in the Ituri Rainforest, and Richard had found out something interesting about the Virunga chimps:

The upper slopes of the volcanoes have porous soils and rock, and no habitual lakes, ponds or long-lived streams. Water falls from the sky and disappears beneath the surface of the volcano, to come out near the base of the mountain as springs, but in the main not accessible for drinking by the denizens of the high forest itself. Animals that live in the forest get their water mainly from very short lived puddles on the surface or from tree crotches, where branches separate and tiny puddles form, and possibly from canopy plants that hold water. During the two month dry season these sources of water dry up and any animal that requires daily drinking must migrate out of the forest or die.

But the chimps, who do require daily access to water, don't migrate out of the forest. They can't. The habitat they live in is circumscribed and can't leave. Well, individual chimps probably do leave now and then and some of them manage to find other suitable chimp habitats, but for the most part the chimps are trapped in a habitat without drinkable surface water for seven to ten weeks or so per year.

It turns out that the plants that live in this habitat are also water stressed, and some of them have interesting evolved adaptations to this. One viney plant, a kind of yam, has evolved a huge underground storage organ that swells as it collects water all year, then provides water during the dry season.

This yam is about the size of a coffee table or maybe a small couch. That is quite large for a yam. And it is loaded with water.

And ... you guessed it: The chimps dig these tubers up and drink from them during the dry season.

This may or may not impress you but it should. Of all the species of vertebrates, hardly any use roots of any kind for any reason. Probably only mammals. Of mammals, bears, pigs, and rodents include species that use roots to some extent. Among primates it is not generally thought of as a major adaptation. Nearly 300 species of primates have fewer than four or five (including these chimps and humans) that ever use roots. And these chimps are the ONLY chimps known that dig for roots.

There is a lot more to this story than the Virunga chimps or my work with foragers in the Ituri. There is work by other people on pigs and bears, there is work by my friend Betsy Burr on rodents, and there is information from the fossil record. But the conversation I mention above at DeVore's house led, after considerable time dicking around with it, to this: The rise of hominids as an adaptive shift in fallback foods: Plant underground storage organs (USOs) and australopith origins. In which:

We propose that a key change in the evolution of hominids from the last common ancestor shared with chimpanzees was the substitution of plant underground storage organs (USOs) for herbaceous vegetation as fallback foods. Four kinds of evidence support this hypothesis: (1) dental and masticatory adaptations of hominids in comparison with the African apes; (2) changes in australopith dentition in the fossil record; (3) paleoecological evidence for the expansion of USO-rich habitats in the late Miocene; and (4) the co-occurrence of hominid fossils with root-eating rodents. We suggest that some of the patterning in the early hominid fossil record, such as the existence of gracile and robust australopiths, may be understood in reference to this adaptive shift in the use of fallback foods. Our hypothesis implicates fallback foods as a critical limiting factor with far-reaching evolutionary effects. This complements the more common focus on adaptations to preferred foods, such as fruit and meat, in hominid evolution.

I don't think this happened in the Virungas, because as I mention above, they are relatively young volcanoes. It may even be that nothing like this happened at all. The significance of the observation may be simply that chimps can make use of USOs. The last common ancestor of humans and chimps was probably a lot like a chimp. So, the Virunga chimps simply demonstrate that this early population may have been able to use roots for something (water or food) and further demonstrates that the use of this resource could be not only something that some groups use, but that a particular group can survive because of. That is important because of all the interesting things chimps do, like using tools to get termites or various "symbolic" behaviors to communicate, none are done by all groups of chimps, and most or all of these behaviors seem to come and go randomly and do not have a high impact on survival. But the root digging and drinking of the Virugna chimps can't disappear as a strategy in this one group; They depend on it for survival.

It is also not certain that such a context (a truly dry two months or so per year) requires volcanic sediments, but this does seem like a very likely location for such a thing. A similar thing happens on the Kalahari sand sheet, where water is abundant, but only if you are able to get at the water which is meters, or tens of meters, below the surface. However, I am pretty sure that there is not a huge water-abundant tuber of this type in th Kalahari. But perhaps at one time there was.

Evolving away on the upper slopes of a volcano would have other effects a well. Like, unfortunately, occasional local extinction. Of course, it would also be a great place to "discover" fire ... But that is an entirely different story, for another time.

_________________

Recent Kenyan Newsreel:

Earlier film on the Nyiragongo volcano (near Nyamuligira) and the region:

LADEN, G., & WRANGHAM, R. (2005). The rise of the hominids as an adaptive shift in fallback foods: Plant underground storage organs (USOs) and australopith origins Journal of Human Evolution, 49 (4), 482-498 DOI: 10.1016/j.jhevol.2005.05.007

gregladen Mon, 01/04/2010 - 09:40

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It is also not certain that such a context (a truly dry two months or so per year) requires volcanic sediments, but this does seem like a very likely location for such a thing. A similar thing happens on the Kalahari sand sheet, where water is abundant, but only if you are able to get at the water which is meters, or tens of meters, below the surface. However, I am pretty sure that there is not a huge water-abundant tuber of this type in th Kalahari. But perhaps at one time there was.

It certainly doesn't -- there are big parts of the "desert" Southwest that have two-month or longer dry seasons. The "sky island" habitats such as Arizona's Mount Graham are isolated arboreal environments separated by some extremely dry country, and the arboreal biomes indeed include not only deep-rooted plants able to reach groundwater but also tuberous water-storing plants -- as do the lowlands, with plants such as Macfadyena unguis-cati and Antigonon leptopus, which thrive on intermittent rainfall in sandy soils.

Well, what is needed specifically here is a dry season in a rain forest where the groundwater does not produce streams that run all year. All the East African and Central African chimps live in a rain forest with a dry season of about 2 months or so (and when I say "dry" I mean nothing other than "no rain at all") but the streams continue to run because there is enough rainfall.

The cloud forests are one possibility, but there are no "cloud forests" that know of that have no streams or other surface water in central or east Africa (though maybe in Sierra Leone in West Africa).

But yes, there are probably other ways for this to happen. But you need a lot of permeable depth.

If I remember correctly, there was a paper in Science a few years back showing gene flow between humans and chimps up to 2 mya, until we had that little chromosomal accident. Wouldn't that suggest the kind of allopatry you're talking about? "Islands" of this kind would minimize gene-flow between sister species, allowing inter-fertile species to remain isolated for extended periods of time, with intermittent periods gene exchange when the islands became temporarily connected and populations shifted.

It also suggests different kinds of biogeographic isolation that must have been involved in our bushy ancestry -- who believes that if chimps and australopithecines could interbreed, that later Homo's couldn't as well?

That is exactly what I would expect a frog to say.

Your paper is very interesting, particularly the difference between food abundance in rainforest vs savanna. The relative deficiency of edible roots in the rain forest vs the savanna might explain why the people that inhabit rainforest (the pygmies) tend to have short stature, it could be an adaptation for reduced food supply (as also occurs on islands) rather than an adaption for early reproduction. Since non-pygmies in the west go through menarche at less than age 12, earlier menarche would seem to be easier to evolve than differential regulation of growth.

In looking at wikipedia, there are indigenous pygmies in Africa, Asia, South America and in Australia, and they all seem to live in rainforest.

You could call this the "Mole Ape Hypothesis". People would give TED talks about it. You might even get on Oprah. (Oops, too late!)

Curtis Marean was insisting recently that a bottlenecked human population of ~150Kya? survived because they, uniquely, had learned to exploit shellfish. Each bottleneck would have its own success story, because all their descendants would know the secret, but only one group among them survives the next one. Maybe tubers get a bottleneck of their own.

A view of human evolution as a series of bottlenecks each conditioned on a seminal invention starts to resemble your typical cheap TV drama.

Hominid Lost. Then Found. Then Lost Again. Then Found.

It could be better than a lot of what is on TV now.

Cool. Interesting idea. It is fun to get a look at how the science works behind the scene.

The concept of habituating chimps for tourists strikes me as both very funny and a very bad idea. Wouldn't this leave them more vulnerable to human depredation?

Peter: Yes, indeed! It is a questionable practice if you have a lot of poachers.

On the other hand, chimps can learn the difference between poachers/hunters and tourists. In this particular region, habituating the gorillas to tourists changed the local economy and saved the gorillas. Temporarily.

It is no doubt not an easy decision to make.

A view of human evolution as a series of bottlenecks each conditioned on a seminal invention starts to resemble your typical cheap TV drama.

Hominid Lost. Then Found. Then Lost Again. Then Found.
It could be better than a lot of what is on TV now.

So diplomatic. I would have said "couldn't be worse".

But there are people who would insist that the appeal of this sort of presentation amounts to a racial memory: everyone alive today is descended from a long series of subpopulations selected for interest in how the elders survived adversity. Tragically, such interest is equally satisfied by falsehoods; hence, religion. And TV.

Some chimps use digging sticks to dig up tubers during the rainy season; during the dry season these tubers become increasingly poisonous from alkaloids IIRC.

Interesting that the volcanic soil there is similar to coral atoll soils in that both drain rainwater immediately, so a long dry season is difficult. Technically a "rainforest" which has a long dry season is a monsoon forest, a true rainforest produces its own rain throughout the year, reducing but not stopping during the dry season.

Shallow-water habitats as sources of fallback foods for hominins
R Wrangham, D Cheney, R Seyfarth & E Sarmiento 2009 AJPA 140:630-642

"Underground/underwater Storage Organs (rhyzomes) consumed by hominins could have included both underwater and underground storage
organs, ie, from both aquatic and terrestrial habitats."

Some chimps use digging sticks to dig up tubers during the rainy season; Which chimps? Are you referring to the chimps at Tai? That may actually be one of those behaviors that has come and gone rather than that is required for survival and known to have persistence.

There is also a group of chimps that digs for water. But that is a whole other story and they are not really digging for water, IMO, though I'm not sure if the researchers and I agree on that interpretation.

Technically a "rainforest" which has a long dry season is a monsoon forest, a true rainforest produces its own rain throughout the year, reducing but not stopping during the dry season.

Not according to the classification systems of which I'm aware. However, it is worth noting that if you take the minimum required annual rainfall to be a rain forest and apply it to Africa, there is only one tiny itty bitty rain forest in West Africa and not one bit elsewhere. So, we Africanists tend to ignore that and refer to the parts with the closed canopy and all the rain as rain forests. The problem is that when the classifications were worked out the data from Africa was rare and that which existed was not really used. So there is a Brazilain/Borneo standard, if you will.

Yes, the Wranngham et al paper you cite is one of several extensions of the work that Wrangham and I did earlier.

Interesting that the volcanic soil there is similar to coral atoll soils in that both drain rainwater immediately, so a long dry season is difficult.

Yes indeed, very similar!

Musings on the Aquatic Ape Theory

gregladen — Tue, 04 Aug 2009 08:36:02 +0000

Musings on the Aquatic Ape Theory

The Aquatic Ape Theory is being discussed over at Pharyngula. As PZ points out, an excellent resource on this idea is Moore's site on the topic. Here, I just want to make a few remarks about it.

The Aquatic Ape Theory (AAT) is a human evolution Theory of Everything (TOE) and thus explains, as it should, everything. That is a dangerous way for a theory to act, because if it tries to explain everything then it is going to be wrong in a number of places, and it is going to seem (or even be) right in a number of places but only by chance. (Unless, of course, the TOE is totally rad and really does explain everything.)

For these reasons, a human evolution TOE will generally evolve into a zombie that won't die and can't be killed, potentially eating the brains of science geeks and graduate students for decades. Another example of a human evolution TOE is bipedalism. Here, the idea is that bipedalism explains everything. For a long time that TOE ate the brains of graduate students and the general public and even senior scientists. It no longer does for this reason: We now know that bipedalism evolved millions of years before many of the key human traits that we wish to explain. But the zombie is not completely dead. Many human evolutionists still make the claim that bipedalism was a very important step in human evolution, even though a) we can't explain why it happened and b) there is no solid link between bipedalism and anything else. The fact that we are increasingly realizing that bipedalism evolved in many hominoid lineages may make this TOE go away eventually. So, for now, the Bipedalism Zombie doe not consume brains wholesale. It just scoops out a tablespoon here and a tablespoon there now and then.

The AAT is different from the Bipedalism TOE for a couple of reasons. For one, it was rejected a long time ago by almost all serious paleoanthropologists. It is quite possible that the fact that the theory was being promoted (but not originally generated) by a Welsh non-academic female and that she was being aggressive about it probably influenced more scientists (negatively) than many aspects of the theory. That would be unfair, and it probably was unfair. But after a while, the AAT began to demonstrate other reasons for its rejection.

The AAT, in its various forms over time, has addressed almost every general aspect of human anatomy and behavior and made the claim that an aquatic ancestry is the best explanation for that feature. Some of these claims were absurd. For instance, the "fact" that females have long hair was an adaptation to living in the water, where the long flowing locks of females would be used as life lines for her babies and toddlers ('paddlers'?) floating around her.

One of the best possible forms of evidence for an aquatic phase would be to find other mammals that are not presently especially aquatic (or at least no more than humans), look for physical evidence of that adaptation, and then check for that evidence, surviving as physiological atavisms, in humans. Not finding such atavisms is meaningless, but finding them would be spectacular evidence.

For example, elephants may have gone through an aquatic stage, and this is in fact seen ontogenetically in their kidneys. Do human kidneys also show this kind of evidence? Well, no, sorry, they don't. The fact that elephants would have gone through their aquatic phase much longer ago than humans does not help the AAT here.

When the AAT was first proposed, we had a murky view of human evolutionary history. At that time it was possible to suggest a single phase of evolution during which certain conditions prevailed, and from which a long list of human traits emerged. But since that time our understanding of human evolution has become more detailed and many of the human traits are now seen as having emerged at very different times over a multi-million year period of time. For the AAT to continue to explain all of these traits (hairlessness, bipedalism, large brain, head hair, body fat distributions, body size, leg length and form, atavistic webbed feet, seafaring, intense use of coastal resources such as shellfish, etc. etc.) it would have to be the case that our ancestors were 'aquatic' for millions of years.

For the entire time that the AAT has been extant, the theory itself has been rather murky. Just how aquatic? Were the babies born under water or on land? Was mating done under water? Was aquatic lifestyle facultative or did all hominids do this? All day every day? Was all the food aquatic? On top of this, only a few of the usual candidates for typical mammalian aquatic adaptations are seen in humans. Hairlessness and subcutaneous body fat were, of course, considered early on to be hallmarks of the aquatic adaptation. The fact that aquatic mammals do not vary in hairlessness (very much) and humans do is a problem. The fact that body fat distributions are sexually dimorphic seems to have been missed by the AAT. Or maybe not. Maybe there is a version where the females are aquatic and the males are not. They meet on the beach for romance. Thus, the link our species makes, psychologically, between beaches and romance!!! Aha!!! It explains everything!!!!!

Oh, sorry, ... I've got control now, didn't mean to go off like that...

So, you can see where the theory goes, and how in fact it can't be stopped. The AAT is a zombie theory, untestable because so much of what it proposes has not been framed in a testable way. The AAT remains capable of consuming many more, still untapped "connections" and "explanations." The AAT has consumed many brains, and not all of them particularly susceptible. Just recently, I heard from an excellent, unimpeachable source that a very famous person whom you have heard of is an AAT 'believer.' I found it hard to believe, but it is apparently true. Some day I hope to have a little conversation with this person!

AAT: The theory that keeps giving. And eating brains.

UPDATE: See this video just in.

gregladen Tue, 08/04/2009 - 04:36

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Funny. And I'm glad you mentioned the sexism around the negative view many have of AAT: while it's a load of crap, it wasn't a load of crap because Elaine Morgan championed it for a time, it's a load of crap for the many other reasons you nicely outlined.

I have a hypothesis, which is probably testable through literature review/surveys of scientists, that underrepresented and/or oppressed scientists sometimes, in order to get the attention of the white men who are turning their noses up at them, create or champion TOEs at a higher rate than those not in oppressed groups. It's only one of several strategies, mind you; others include fitting in with the dominant behaviors, keeping your head down, leaving the jerks to themselves, etc, but it could be a strategy for a minority of these folks. Right now Margie Profet and Elaine Morgan come to mind, as do a few others that I'd rather not name for pseudonymity purposes. As a female scientist who found throughout graduate school and sometimes even after I was done that when I said something no one heard it, and when a man said the same thing everyone would nod like it was brilliant, I certainly wanted to wave my hands and shriek at times.

Should "many of the human traits are not seen as having emerged at very different times" read "now seen"?

Now and not... too dissimilar in meaning to be so close in spelling. Such things should not be aribrary! (Clearly, language evolved and was not designed.)

Perhaps this explains mermaids:p A fully adapted aquatic hominid:p Urf! Urf! Hack! Sorry. Hairballs.

For instance, the "fact" that females have long hair was an adaptation to living in the water, where the long flowing locks of females would be used as life lines for her babies and toddlers ('paddlers'?) floating around her.

They don't actually try to make the distinction between male and female hair length do they? Did Aquaman have hair clippers? I sure hope that it is understood that head hair length differences in the sexes is a social thing, and that's another discussion...

Maybe there is a version where the females are aquatic and the males are not. They meet on the beach for romance. Thus, the link our species makes, psychologically, between beaches and romance!!! Aha!!! It explains everything!!!!!

Mermaids? Ooh la la!

But seriously, what the hell is so romantic about finding sand in crevices you didn't even know you had a full week after the escapade? ;-)

jj: Yes, they did, briefly. There is a phrase in the literature somewhere ... "The reason for long hair in women is..."

Robert: Mermaids are to the AAT what bigfoots are to regular human evolution, I suppose.

I highly doubt that mating was done in the water. Anyone who has attempted this knows how difficult it is to thrust correctly without just pushing your partner away. It's much easier to do on land.

"a Scottish non-academic female" - who?

Gav, sorry, I totally neglected to mention Elaine Morgan's name. In my little world she is well known and so closely linked to the AAT that I just (incorrectly) assumed.

(Sorry Elaine!!!)

Not wanting to support a TOE, but is the traditional "plains ape" any better supported than "waterside ape" (or, for that matter, "forest ape")? Even if the Olduvai area was plains at the time (was it really? all of it?) that doesn't tell us much; fossils form where they can, not necessarily where the most specimens died.

I see the visceral reaction as, in part, another example of scientists taking their own discomfort at being obliged to maintain two equal theories as itself evidence against the less historically familiar one. If, for personal reasons, scientists need to keep just one default theory in the absence of evidence one way or another, "waterside ape" seems as good as any. It seems to me a good thing, then, for some fraction of anthropologists to hold it that way, while others relax with "plains ape" and others again with "forest ape". Maybe some real evidence will come along to favor one or another, someday.

Plains? I don't like plains, and I never did. Hominids would never have been common, say, on the Serengeti plains. The evidence suggests that early hominids (australopiths prior to erectus) liked wooded savannas and were tethered to water. There is a lot of evidence for that, yes.

The behavior of AAT advocates exposited on Moore's site seems sufficient to justify a visceral reaction, particularly after decades.

I do wonder about taphonomy, though. If we did have coastal-ape or riparian-ape ancestors in addition to the wooded-savanna dwellers, could the evidence of it survive?

Edge ape? Lived in the edge of the forest so can use plans and forest habitat as needed like many good generalists.

Couple points. My web site is just a web site, not a blog. (I don't have the energy to write a blog :)) Elaine Morgan is Welsh, not Scottish.

And the emphasis on savannas among the supporters of the aquatic ape idea doesn't really mesh with what the prominent theories about human evolution have been saying for decades. Those theories tend to be about food-getting and social interaction, and deal with environment only in describing where those activities happened. Those ideas are not environmmentally deterministic as the AAT/H proponents seem to think, and as the AAT/H is. Hominids used a variety of environments, judging from the fossil sites, which is what you might expect for a creature on its way to becoming perhaps the world's supreme environmental generalist. (Is there any other animal, of any kind, which managed, even before modern technology, to use so many different environments while remaining one species?)

Greg

Excellent, devastating post. I despair when this "theory" crops up on the Science or Discovery Channel, which, alas, it often does.

Maybe you could have a look at Bernd Heinrich's Why We Run as another inflated TOE in need of balloon bursting.

Thank you, Mr. Moore. My information was evidently badly out of date.

Somebody should tell Brad Delong to stop referring to himself and his colleagues as "east-african plains apes". Suggestions for the replacement? "Pan-african ground apes"? Is our wide range of habitats our defining characteristic, as apes? Macaques seem pretty versatile.

Macaques do pretty well on the versatility scale, but we shot past them a million years ago and never looked back.

I didn't register your question though: "I do wonder about taphonomy, though. If we did have coastal-ape or riparian-ape ancestors in addition to the wooded-savanna dwellers, could the evidence of it survive?"

I think this is something that also hurts the aquatic ape idea badly. The areas they suggest our ancestors be in are the areas we'd expect to see loads of them fossilized; so how come we have relatively few hominid fossils and from such a range of environments? They only spots where they have claimed for this semiaquatic phase that might not leave lots of fossils is the beach or tidal saltwater areas, and they've pretty much dropped that idea because of the salt load problem and the fact that our reactions to salt are those of an animal which evolved in a salt-deplete environment. Of course that doesn't stop them from sometimes suggesting the fellows were here for this problem and then, when you point out the problem with that they whip them off to another spot entirely. I refer to this ad hoc method as ZING!ability.

Jim, thanks for the comments and clarifications. (Also, I fixed the errors in the post.)

Hey, Greg, you should put this image in there somewhere
http://www.pollsb.com/photos/o/324788-zombie_cat.jpg

Is the very famous person Dan Dennett? He has a chapter on it in Darwin's Dangerous Idea.

I will never tell unless this person agrees to have a public conversation about it, the you'll know.

The AAT is a zombie theory, untestable because so much of what it proposes has not been framed in a testable way. The AAT remains capable of consuming many more, still untapped "connections" and "explanations."

Surely it's not worse than evolutionary psychology for generating untestable "connections" and "explanations"?

They are really similar in the way they are untethered to actual research questions with empirical anchors.

Humans seem far better adapted at long-distance running than surviving in an aquatic environment. It still seems surprising to me that we can outrun any animal, given a long enough distance.

I'll go for "edge ape" too. I edge away from water all the time. But my wife loves it. In our early days she introduced me to snorkling. Now we have kids we don't bother.

"Honeymoon Aquatic Apes" ?

"Maybe there is a version where the females are aquatic and the males are not. They meet on the beach for romance. Thus, the link our species makes, psychologically, between beaches and romance!!! Aha!!! It explains everything!!!!!"

Curiously among Tasmanian aboriginals (original southern coastal route Out of Africa Culture???) men were not allowed to go into the sea, mostly I suspect because this was women's work (gathering crayfish, abalone, other shellfish), men would even be pushed across on boats to islands that the women pushed while swimming (apparently). (Scalefish were not eaten at the time of British colonisation, possibly taboo. Scalefish bones are in the archeological record of middens but not after about 4000 years ago. Some hunter-gather political dispute no doubt. Tim Flannery says they just forgot but I reckon it was political, everything is.

Not Scottish, Greg. I'm Welsh.

Not quite non=academic. It's Dr. E Morgan M.A (Oxon) FLS
FRSL OBE to be precise.

Elaine Morgan's doctorate is an honorary doctorate from the University of Glamorgan. The university's guidelines for proferring these honors are:

Where the contribution is in a field related to an academic discipline, a specific Doctorate (e.g. DSc, DLitt) will be awarded; in other cases, a Doctorate of the University will be awarded.

Morgan's honorary doctorate was a DLitt (Doctor of Letters) indicating they gave it to her for her literary work rather than her aquatic ape work. Not that she's trying to put one over on anyone. :) She does have several honorary fellowships as well.

OK, I changed scottish to welsh a while back (I am a typical confused American who makes silly mistakes like calling Elizabeth the Queen of the British and so on) and I meant non-academic as a compliment, really.

"They are really similar in the way they are untethered to actual research questions with empirical anchors."

Well composed sentence there, Greg, but entirely untrue. Without supporting AAH or any other theory, I'd like simply to point out that indeed, AAH definitely has REAL ACTUAL QUESTIONS (which the theory is "tethered" to) that it hopes to answer with EMPIRICAL (observed) ANCHORS (information).

Example:

Why are we hairless? (Actual Research Question)
Empirical Anchors:
1) sometimes aquatic and subterranean mammals lose much of their hair during evolution because it can no longer thermoregulate temperature properly
2) those same mammals also sometimes evolve subcutaneous fat because it does regulate properly

Valid, actual, empirically driven hypothesis: Maybe homo sapiens are hairless because we evolved in a semi-aquatic environment! Eureka!

human, research questions are the testable sort. "Why" is not testable.

ahuman: Not really. Most of the aquatic ape 'hypotheses' started out as interesting ideas (naked mammal, subcutaneous fat) but when examined more closely and broken down into ontogenetic, functional, and phylogenetic components they don't hold up. For instance, consider the functional aspect of naked skin and subcutaneoius fat. Two problems emerge right away. 1) aquatic mammal surfaces to get naked and underlain by fat, but that skin also covers a body with shortened appendages and other shape changes. The functional shift of interest is adaptation to an environment where the matrix sucks away heat. Changes in body shape are far more important than hair, for instance, yet they don't happen. In other words, functionally, the human skin adaptation is not even close to being explained as an adaptation to spending hippo-amounts of time in the water (to make an appropriate direct comparison).

2) Subcutaneious fat distribuiton, if for thermoregulation, would be distributed uniformly or greater over heat loss surfaces. But in fact, they are distributed (in humans) the exact OPPOSITE way, as would be predicted by an alternative hypothesis: Food storage without losing high thermal LOSS abilities (not retention, as a mammal would require spending a lot of time even in warmish water).

Fat and hair are interesting, but on very preliminary examination it becomes clear that the actual adaptation is heat LOSS (and that also wipes out your naked fossorial mammals from the equation, by the way) for aquatic mammals not just nakedness or having extra fat.

In other words, it's like saying a "long appendage" is good for seeing father away or eating leaves off the top of a tree) like a giraffe) but the appendage you are looking at is a tongue (as in woodpeckers, for probing).

Untethered. Way.

In response to Greg Laden:- Those seals which lost their fur and went the subcutaneous fat route have little fat on their flippers ("heat loss surfaces") - increasing SQ fat makes things rounder and round hands / flippers would be tough to swim with.
The endurance issue is important - I have seen it used to explain our need for nakedness - so that we wont overheat and can run down animals over long distances in the hunt. This is unlikely. On the Savannah, predator/prey chases are all over in a few seconds. Large predators hunting us can all outrun us over short distances - so we would never get the chance to show how well we can run marathons. Lion /leopard/hyena and Usain Bolt and he is just lunch (don't even think about the cheetah).Similarly, even San ("Bushmen") hunting must slow down their prey with poisoned arrows to be able to catch them. It is not possible to run down (while tracking) a healthy plains antelope. On the other hand, a semi aquatic ape which does not have the ability to endure while swimming will simply drown. It is far more likely that we evolved the physiology of endurance (which is far more than just the ability to keep cool) in response to the challenge of swimming than of hunting. Our ease on two legs running now (compared to swimming) should not fool us into believing it was always so. Certainly at first we would have been as clumsy and slow as a chimp on two legs. So what was the immediate one step benefit for doing so? We cannot argue that we started walking on two legs because we knew that in a few thousand generations we would get good at it. Walking in water and keeping your nose out of the water by standing on your hind legs is just such a one step benefit.
If comparing how well and with what enthusiasm humans swim compared to run, we should also compare how well chimps run and swim. Clearly we are relatively hugely better swimmers and they are better runners.

Greg, I don't think you even understand what these ideas are. The "aquatic ape" is a misnomer. It's not one idea, it's several. It's not arguing that our ancestors were "aquatic" in any commonly accepted sense, just more aquatic than the lineage leading to chimps/bonobos/gorillas since the split. It's not necessarily suggesting that this "more aquatic" pressure only occurred as apes, but could also include relatively recent human ancestry.

Admit it. You heard about this idea over a coffee or a beer when colleagues sneered at it and you've been sneering at it ever since, right?

You say "... it was rejected a long time ago by almost all serious paleoanthropologists" so, ok, where was that rejection published?

You mean John Langdon's unscholarly, straw man portrayal that had no reply until recently? (See here http://www.waterside-hypotheses.com/viewtopic.php?f=10&t=133 for a discussion, with John, of my critique of his) Or Roede et al - where the decision "against" was rather marginal and even then the editors made it clear that (like you) they were considering a "full on" aquatic ape, not the concept that perhaps our ancestors were subjected to slightly more selection from wading, swimming and diving than the chimps?

You mention the "bipedalism TOE" which, I agree, has been used to explain everything, but you fail to notice the overlap here - the wading hypotheses has to be one of the most obvious and plausible, and least anthropocentric, ideas on hominid bipedal origins.

Perhaps in a future blog you might cite that paper where the idea was "rejected" by paleoanthropology because I've been doing a PhD on the subject for years and I cannot find one that so much as even discusses it specifically.

Finally, you ape PZ's incritical backing of Jim Moore's masquerading web site and label it as "excellent". I doubt either of you have even read it.

If you had, you'd note the nauseating hypocrisy throughout - e.g. he criticises Elaine Morgan for not using page numbered citations when almost all of his gossip takes the form "aquatic proponents tend to say x about y" - with no citation at all.

Normally, in science, we use the scientific, peer reviewed literature to refute ideas. Here, I note, the bar has to be lowered so much that the biased twistings of an ex-car mechanic without any academic training in science other than a nepotistic link to Nancy Tanner, can substitute with impunity.

You, like Jim Moore, should be ashamed of yourself for trying to pull the wool over people's eyes like this.

Algis Kuliukas

Algis, your uniformed hubris made me laugh this morning. Yeah, it was a lot like sneering at ideas over a beer but it was actually getting a PhD in the study of human evolution and stuff! But yes, there was sneering and there was beer.

Hey, here's a new bit of information: When we put my baby in te water, he sinks right to the bottom. He's been taking swimming lessons or otherwise swimming with his grand dad or mom once or twice a week sine he was about 6 months old (he's now 2 1/2). He still sinks right to the bottom if he is not being held or wearing a flotation device. I'm told this is normal for human children.

Therefore your ideas are rong!!!!11!!

I first heard about AAT in _Time Magazine_ in the early 70s. _The Descent of Woman_ was a delight to read, even if, as Steve Gould said about the Gaia hypothesis, "It's poetry, not science." (Personal communication, 1986.)
I think in general that to avoid political confusion in the general American-speaking population, one should avoid the term "theory" except in cases when it is a proven hypothesis, such as gravity, relativity, and natural selection.
Re: AAT: Do other species of great apes have a diving reflex? "I'm just askin'" (âthe B-52s).

The "Diving Reflex" is a mammal wide trait, it would seem, although no one has ever tested anything on all mammals, it is known in a wide variety of mammals. It is also found in many birds (I don't know of any birds it is not found in, but again, no one has ever tested anything on every bird).

It is activated by cold and not warm water, so I suppose one could wonder about the evolution of hominids in tropical regions vs. the cold-water diving reflex! In any event, the diving reflex is probably plesiomorphic for mammals, or vertebrates, or some other large taxonomic category, so it is not helpful in identifying the AT "theory/hypothesis" (both words have been used at different times by its proponents)

Greg thanks for confirming that your bias against this idea is based on a sneering session and that you are somehow proud of this ignorance.

Oh, so because your baby sinks (N = 1) suddenly that data must override everything else, is that it? Oh and you "were told this was normal for human children"? Brilliant! Kind of like the argument "well my grandad, who's 75, smokes 20 a day, and he's ok. I was told this was normal, so I'm skeptical about all that cancer stuff."

Blimey, Greg, with aquaskeptic arguments like this, who needs science?

Your final point (it seems, made after a one too many of those beers) was damning...

"Therefore your ideas are rong!!!!11!!"

It's the paucity of the arguments against waterside hypotheses - as you admirably show here (I note, not one word about Jim Moore's masquerading web site - I bet you haven't read more than a few sentences of it) - that most convince me that it is probably right to some degree.

Algis Kuliukas

Two chimps walked into a bar ...

gregladen — Thu, 12 Feb 2009 14:43:12 +0000

Two chimps walked into a bar ...

... and made a real mess of the place when one of them spotted the jar of pickles on the counter. They fought over it until one of them had almost all the pickles and the other one had a number of bruises and a tiny fragment of one pickle that the other chimp dropped by accident.

That would be the way it would happen if two chimps walked into a bar. Or imagine two chimps, and each finds a nice juicy bit of fruit out in the forest. And instead of eating the fruit, because they are not hungry, they carry it around for a while (this would never happen, but pretend) and then accidentally run into each other. What would happen? Same thing. Event though neither chimp actually needed the fruit and each chimp had its own fruit, the dominant chimp (between the two) would end up with both pieces of fruit.

This is why chimps could not possibly cooperate in any effort to scour the forest for various edible items, bring them all back to a central place, share and then cooperatively process the food items, and ultimately produce a meal that is eaten by all of the chimps on an as needed basis. Humans do that but chimps can't. Explain this and you explain one of the major features of human evolution...

Some of us think that about two million years ago, an ape-like hominid ancestral population for humans gave rise to individuals with the novel capacity to do the following:

1) Make and control fire;

2) Cook food on this fire; and

3) Cooperate enough that individuals could in fact bring food morsels to a central place for processing and sharing.

The consequences of this nexus of novelties would be significant. There would be much more energy in the environment available for consumption because cooking converts a lot of inedible biomass into edible biomass. This could supply the necessary nutrients for bodies to grow larger and be maintained at larger sizes, which might be useful in the predator-rich environment of Africa. Note that where we can determine cause of death for australopiths, or at least guess reasonably what it might have been, predators are typically involved. This seems to stop happening with the larger bodied Homo erectus following this transition.

Another consequence is the extra nutrition to support the growth and maintenance of a large, costly brain.

These early human ancestors would have to have a way of cooperating rather than (almost) always competing over things like food. This could result in behaviors supportive of more complex and sophisticated technologies being regularly used, as we in fact see in the archeological record. The novel food sources plus the additional technology together would support this species' movement into additional habitats previously not occupied by hominids. We also see this happening just at this time in the archaeological record.

For various reasons I won't go into here, this would also have surely changed the overall social organization among these hominids, and we suggest that this may have been the origins of something not entirely different from modern (more or less monogamous) marriage.

(Here is a copy of a paper that discusses this idea in some detail.)

gregladen Thu, 02/12/2009 - 09:43

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It's simple. The female hominid discovered fire and how to use it. Filing in the blanks becomes easy now.;-)

Most likely exactly that. Female primates generally are the technology savvy where there is technology being used by a species. Mother to daughter transmission is key in all of these species . With CPF (Central Place Foraging) Mo-Da transmission may become less relatively important, but it would be key early on.

It would be later in prehistory that males would start bonding with each other across time using various phallic artifacts like spear points and such.

Explain this and you explain one of the major features of human evolution...

impulse control. chimps don't have it, and humans may have developed it through a filter of symbols. this NOVA had a good breakdown:

http://www.pbs.org/wgbh/nova/apegenius/

a chimp is given a choice of two candy dishes with different amounts of candy. the one that the chimp chooses is given to a *second* chimp, while the chimp-chooser gets the other dish. the chimp-chooser invariably *always* reaches for the dish with more candy, no matter how many times it learns that by trying to pick more, it gets less

repeated with symbols (numbers representing candy, instead of candy), the chimp-chooser "gets" the game, and starts picking the lower number, thus getting more candy

i probably explained that badly. Happy Monkey anyway!

Do mother chimps bring "home" edibles for weaning/post-weaning chimplets?

No, they don't bring stuff 'home' .. the weannies attempt to take the food from mom (right out of her mouth often) and mom tolerates it to varying degrees.

No, they don't bring stuff 'home' .. the weannies attempt to take the food from mom (right out of her mouth often) and mom tolerates it to varying degrees.

..and in a broader sense, this differs from Homo sapiens weenies, how?

Damned weenies.

and we suggest that this may have been the origins of something not entirely different from modern (more or less monogamous) marriage.

consider that in most mammals, the female stops being sexually receptive as soon as she becomes pregnant. This does not happen like that in humans.

Two things strike me as very different in humans: 1) the aforementioned ability cooperate effectively and 2) very long period of dependency for the young.

Whereas in a non social but intelligent mammal (racoon for instance) having the male around would just be more resources required, and the mother can survive reduced food intake long enough to get the young mobile, with humans, keeping the male around can inprove reproductive success. Perhaps then, females who did not 'turn off' had a reproductive advantage over those that did. Bingo 'long term mating'

Darwin had noticed that while in most animals males competed for females, there seems to be some female competition in humans. My understanding is that he seemed to think of it as a reversal, but in essence it is a parallel competition. Males compete for the scarce resource (a fertile female) females compete for a scarce resource (a male who will actually stick around and provide resources for the young). This would suggest that makup, hair dressing, jewelry and killer heels are actually an indirect byproduct of this long term mating strategy.

Or, more precisely, that this mating strategy produces impulses that purveyors of Overpriced Crap can hijack to sell people things they don't need and didn't want.

I spend a lot of time with captive chimps. Sharing, as Greg noted, is not often practiced. And fights can break out over food. But one thing I have noticed is that they don't fight over non-food "stuff."

They get non-food enrichment items (blankets, clothing, stuffed animals) and one of the girls might carry an item around for hours or even days. But when she puts it down and another chimp picks it up ... nothing. No reaction. No trying to get it back. I've never seen them get emotional about stuff.

Gerry. Obviously you have not given them a Nintendo.

But seriously, interesting point.

One of the things that occurred to me during your presentation last night was that in addition to providing more energy with less food through cooking (shifting resource allocation from the gut to the brain,) waiting for the dinner grew into an opportunity for greater socialization among the group at "dinner time."

This may venture a bit deeply into evolutionary psychology; but here goes.

With the increased time of socialization, the small group developed more complex communication tools over time. I'm thinking language here. Would it have also created the sort of mechanical solidarity that engenders the growth of larger groups into tribes and bands?

Do we know enough about neandertals to say whether or not they cooked their food? If not, would that help explain the ascendancy of the cro-magnons?

I did feel a little sorry for the people last night who didn't know this was available here. You did well, but the time for talking about any part of this was so short.

But Lynne did a great job telling people to get to this blog, so hopefully people will look around.

AFAIK male chimps in the wild bring back meat from hunting trips and share it out among some of those (especially females) who didn't go on the trip. (See many books and articles on chimp behavior in the wild.)

My impression is that they are very Machiavellian in their choice of recipients and "cuts" of meat involved, however that may be the bias of the particular authors I read on the subject.

I know Goodall was probably over-enthusiastic in her early conclusions regarding meat-sharing ("chimps always share meat while never sharing anything else"; paraphrase), but there is much evidence for meat sharing and a good deal of speculation (and debate) regarding the origins/motivations.

A quick search located The Predatory Behavior and Ecology of Wild Chimpanzees, as well as Meat sharing among the Gombe chimpanzees: harassment and reciprocal exchange. The latter attempts to demonstrate that meat sharing is primarily in response to harassment.

While searching, I also discovered Chimpanzees Share Forbidden Fruit, which documents sharing of plant food by males. This appears to be limited to human crops "raided" by parties of males, who clearly take risks and know it in making these raids.

Somewhat in line with the article's conclusions, I would suggest that in general food is shared when its acquisition involves status-enhancing activity, as a means of trading individual demonstrations of prowess for enhanced status within the community. This is roughly parallel with similar food-sharing by human hunters (no time to find links, but see various descriptions of San lifestyles). Indeed, one description I read of responses to successful hunters involved verbal harassment to encourage sharing that was very analogous to that described by Gilby (see link above).

My suggestion, then, is that chimpanzees (and bonobos) posses the same Machiavellian sharing impulses as humans, including the recognition that contributions to the group welfare can be traded for enhanced status within the group.