behavioral biology
gregladen | June 30, 2010June is almost over, and with nary a comment from this blog on rape. But June is the month we normally discuss this important problem. So to comply with that idea, I'm going to point you to a couple of posts from last year. If you've not read them, please have a look. Especially read the comments. Things got ugly, but they also got interesting.
A rape in progress
"I am a scientist observing the culture of the Namoyoma people. I am sitting in a shady spot just outside the village, writing up some notes, and I observe a disturbing event. Four men are trying to drag a young woman from the…
gregladen | October 26, 2009Do Individual Females Differ Intrinsically in Their Propensity to Engage in Extra-Pair Copulations?
A repost
Now, this is truly important applied science, in PLoS.
While many studies have investigated the occurrence of extra-pair paternity in wild populations of birds, we still know surprisingly little about whether individual females differ intrinsically in their principal readiness to copulate, and to what extent this readiness is affected by male attractiveness.
Oh, it’s about birds … well, it’s still interesting.
For decades, and even to this day, much of the discussion of behavioral…
gregladen | October 15, 2009Constructivism. Determinism. It is all a bunch of hooey.
A recent paper published by PLoS (Culture Shapes How We Look at Faces) throws a sopping wet blanket on widely held deterministic models of human behavior. In addition, the work underscores the sometimes spooky cultural differences that can emerge in how people see things, even how people think.
A Repost
The following is from a PLoS press release:
Because face recognition is effortlessly achieved by people from all different cultures it was considered to be a basic mechanism universal among humans. However, by using analyses…
gregladen | September 25, 2009The Anglo Boer War (in what is now South Africa from October 11th, 1899 to May 31st, 1902) was a turning point in European style military history. Previously, infantry would operate in large blocks that would move forward, turn and open or close ranks, and winning an infantry engagement would involve getting your columns around the side or back of the enemy's columns, or simply overrunning them head on. This worked in part because although everybody had a firearm of some kind, the firearms held few bullets, took time to reload, and were inaccurate, and since they tended to be inaccurate,…
gregladen | September 2, 2009Today's falsehood is the idea that individual animals act for the benefit of their own species.
Let me give you an example. When I was a kid, I watched a nature show about cougars. The show 'documented' a single female cougar going about doing cougar-things and being generally cougar-like. At one point she had cute little baby cougar kittens.
Then a flood came. The stream near her chosen lair swelled its banks and threatened to drown the kittens. So, she carried one of the kittens up the hill to a new lair. She went back to get the second kitten, and the flood waters were even higher…
gregladen | August 31, 2009Good morning and welcome to another installment of "The Falsehoods." Today's falsehood is the assertion that the poor have more babies than the rich, or that the poor just have more babies to begin with. In comparison to ... whatever.
Now, before you rush off to the Internet and find some table or graph that shows higher fertility in women of lower SES than higher SES, or a high birth rate among Nigerians, I want to acknowledge right away that such evidence is easy to find, and it is easy to take that evidence and construct the obnoxious sentence that titles this post. Yes, that is all…
gregladen | July 27, 2009Is the Natural World a valid source of guidance for our behavior, morals, ethics, and other more mundane areas of thought such as how to build an airplane and what to eat for breakfast?1 When it comes to airplanes, you'd better be a servant to the rules of nature (such as gravity) or the airplane will go splat. When it comes to breakfast, it has been shown that knowing about our evolutionary history can be a more efficacious guide to good nutrition than the research employed by the FDA, but you can live without this approach and following FDA guidelines will not do you in. A naturalistic…
gregladen | June 30, 2009This post was originally titled "Mail Order Brides and Hypergyny." I was prompted to revisit the post because it received a a rather astonishing comment that I chose not to allow, but I did post it on my Facebook page where any attention it would receive would be from the thoughtful people that make up my Facebook community rather than just anybody out there on the Internet. Also, I recently received a complaint from a reader that Scienceblogs.com has been showing a lot of ads for "mail order brides," and this post was originally partly a response to that.
I should also mention that in the…
gregladen | June 30, 2009 Although the paper addresses Tanzanian lions, this is a photograph of a Namibian lion Starting some years ago, we began to hear about revisions of the standard models of lion behavioral biology coming out of Craig Packer's research in the Serengeti. One of the most startling findings, first shown (if memory serves) as part of a dynamic optimization model and subsequently backed up with a lot of additional information, is the idea that lions do not benefit by living in a group with respect to hunting. They live in groups despite the fact that this sociality decreases hunting effectiveness…
gregladen | June 2, 2009Or to put it more accurately, yet another study seems to show that girls learn from their teachers, parents, and peers that they are not supposed to be good at math. Sterotypes can be fulfilled. Pleas stop doing that, everyone.
Here is some press on this story.
University of Wisconsin-Madison researchers continue to find evidence that shows there is no innate difference in the math ability of males and females.
"There is a persistent stereotype that girls and women are just not as good at math as boys and men," said UW-Madison psychology professor Janet Hyde. "And the data we have…
gregladen | May 14, 2009Why does a soldier throw himself on a hand grenade to save the lives of a half-dozen unrelated fellow soldiers? Why does someone run into a burning building they happen to be passing to save a child they don't know? From a Darwinian perspective these seem to be enigmatic behaviors that would "select against" such individuals (or more properly, select against the heritable component of this behavior).
There are several possible explanations for this....
...The most important one might be that this sort of behavior doesn't really happen very often. It is so rare that it can be ignored and…
gregladen | May 12, 2009According to a study just coming out in the Journal of Sexual Medicine, "variations in emotional intelligence--the ability to identify and manage emotions of one's self and others--are associated with orgasmic frequency during intercourse and masturbation."
In short, the study found:
Emotional intelligence was not associated with ... age and years of education, nor did we find a significant association between emotional intelligence and potential risk factors for [female orgasmic disorder] FOD such as age, body mass index, physical or sexual abuse, or menopause. We found emotional…
gregladen | April 28, 2009Gallup has taken on the task of explaining, in ultimate terms, the evolutionarily designed features of the human penis. He works this as an engineering problem from the perspective of evolutionary psychology, which is always a little bit dangerious, but gallup isn't quite the arm waiver that a lot of other EP's are, so he may be doing it right.
Gallup's work is written up an an all-too-sophomoric Scientific American article by Jesse Bering which just barely falls short of explaining this important biological phenomenon in terms of a pair of headlights, a flashlight, and a little red waagon.…
gregladen | March 25, 2009As you know if you read my blog, Trivers Willard is an important theoretical construct which has been tested numerous times. TW works in some species, not in others, and overall, that should be predictable (accroding to TW).
It turns out that finches control the sex of their offspring, and do so in a way that TW would predict, apparently. There is a paper in Science that I'll probably eventually get to writing up for you, and in the mean time, here's a quick news report from Scientific American.
See if you can figure out how Trivers Willard is working here, and why the important…
gregladen | March 6, 2009I'm starting to worry that the last few Friday Weird Science write-ups by Scicurious (who seems, these days, to be the primary blogger at Neurotopia) have been of papers that I happen to have read. Just so you know: Thousands of papers are published per week across the diverse sciences, and although Scicurious tends to deal with life science and I tend to read life science, the chances of this particular harmonic convergence across bloggers regarding papers published over the last decade is statistically almost zero. More likely, Scicurious and I just have similar taste ... or lack thereof…
gregladen | February 25, 2009The male and female human brains are different. Some of the better documented differences are similar to differences seen in other mammals. They are hard to find, very small, and may or may not be of great significance. Obviously, some are very important because they probably relate to such things as the ability ... or lack thereof ... to bear offspring. But this is hardly ever considered in the parodies we see of these differences.
[Repost from Gregladen.com]
You have all seen the sometimes funny, sometimes not cartoon depictions of these differences, for example this one:
Obviously,…
gregladen | February 25, 2009Go to any bar and you'll see a lot of males standing and sitting around not mating. I'll bet you would have guessed that the reason they are not mating is that no females will mate with them for one reason or another. But there is the distinct possibility that they are very inconspicuously resisting mating opportunities. It turns out that males can do this .... avoid mating without conspicuous resistance ... more easily than females. For obvious reasons.
This could be why what has become (inappropriately) known as "reversed sexual aggression" often goes unnoticed, and a recent study of the…
gregladen | February 25, 2009 Why is there no Birth Control Pill for men?
The answer I'd like to propose can be summed up in two closely linked words pilfered from the question itself:
Men. Control.
Myriad aspects of life can be understood by recognizing a single critical fact, and the layered, sometimes complex, deeply biological effects of that fact. Males, by definition, can't have babies.
All mammalian males contribute to the reproductive endeavor, but often this contribution consists of a single cell, one per offspring. True, that cell contains a haploid copy of the male's DNA, the quality of which is…
gregladen | February 24, 2009Is chimpanzee food sharing an example of food for sex?
One of the most important transitions in human evolution may have been the incorporation of regular food sharing into the day to day ecology of our species or our ancestors. Although this has been recognized as potentially significant for some time, it was probably the Africanist archaeologist Glynn Isaac who impressed on the academic community the importance of the origins of food sharing as a key evolutionary moment. At that time, food sharing among apes was thought to be very rare, outside of mother-infant dyads. Further research…
gregladen | February 24, 2009Why did humans evolve hairlessness? Hair (fur) protects mammals from heat and cold, what would be the benefit from losing this asset?
I think the most commonly held theory is that fur works on quadrupeds, but once you stand upright, it is less effective, and less fur works better. For later time periods, clothing works better than fur because it is more adaptable. Consider that whatever fur-based system human ancestors had was based on needs in the tropics where it does not get that cold, so it is not hard to imagine that clothing is much more effective.
Recent studies of body parasites…