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WMAP results: Cosmology from the CMB

The cosmic microwave background is the radiation left over from the big bang. It's very uniform, 2.725 Kelvin everywhere. We're moving with respect to it, so there's a doppler shift, and we see that as a dipole moment in the Temperature. When we subtract that out, we see variations on the order of 30 microKelvins! WMAP is a satellite (Wilkinson Microwave Anisotropy Probe) that measured these anisotropies, and they just released its year 5 data. First off, with the uniform and dipole parts subtracted out, and with the foreground from the galaxy also taken out, here's the map of the microwave…

The Ebb and Flow of Lunar Science

The picture above is what the Moon would look like if you wore gravity glasses. We've been following the Grail Mission for some time now, and new results are in. NASA has made a very detailed gravity map of the moon. The Grail mission involves the use of two space craft flying next to each other, keeping track of their relative position by the use of radio signals. As they pass over the moon's surface, they also interact with the Moon's gravity. The complex dynamic of interaction between the twin spacecraft and the moon is measured by highly sophisticated and sensitive equipment, the data…

Okay, One More

I have a couple hours before I have to get hit the road, so let me throw out one last summation on the missing explosives. The videotape provided by the Minneapolist TV station, taken on April 18th, has now been conclusively shown to contain footage of the very explosives that are now missing. David Kay, first head of the Iraq Survey Group, was on CNN last night and said the following: Well, at least with regard to this one bunker, and the film shows one seal, one bunker, one group of soldiers going through, and there were others there that were sealed. With this one, I think it is game, set…

TRPV1 Ion Channels

I noticed that PZ posted one of our take-home exam questions on Pharyngula and so I decided to make an entry with my answer (I okayed this with PZ first although he did warn me of the certainty of harsh reader criticism). The question referred us to a recent article in Nature about TRPV1 ion channels and asked us to describe TRPV1 ion channels and the testing that was done on them. The transient receptor potential cation channel (TRPV1), also referred to as vanilloid receptor subtype 1, is a ligand-gated cation channel (2). This means that the channel contains organic molecules that can…

How to admit you're wrong

We all make mistakes. And even the most humble among us can be a little self-righteous when it comes to our pet projects. But when was the last time you came across a self-righteous pseudo-skeptic who had the decency to admit to getting it completely wrong? Meet Steven Goddard of The Register, a peculiar little news outlet published in London. Sort of. Goddard wrote a piece that appeared on Aug. 15 under the bold headline "Arctic ice refuses to melt as ordered." As anyone who has been following the plunging arctic sea-ice extent graphs at the National Snow and Ice Data Center can attest, this…

Attack of the killer tomato fungus driven by mobile weapons package

In Robert Louis Stevenson's classic story, Dr Henry Jekyll drinks a mysterious potion that transforms him from an upstanding citizen into the violent, murderous Edward Hyde. We might think that such an easy transformation would be confined to the pages of fiction, but a similar fate regularly befalls a common fungus called Fusarium oxysporum. A team of scientists led by Li-Jun Ma and Charlotte van der Does have found that the fungus can swap four entire chromosomes form one individual to another. This package is the genetic equivalent of Stevenson's potion. It has everything a humble, Jekyll…

Resistance to an extinct virus makes us more vulnerable to HIV

Immunity to viral infections sounds like a good thing, but it can come at a price. Millions of years ago, we evolved resistance to a virus that plagued other primates. Today, that virus is extinct, but our resistance to it may be making us more vulnerable to the present threat of HIV. Many extinct viruses are not completely gone. Some members of a group called retroviruses insinuated themselves into our DNA and became a part of our genetic code. Indeed, a large proportion of the genomes of all primates consists of the embedded remnants of ancient viruses. Looking at these remnants is like…

Higgs Hates Us?

Supposedly there's no such thing as bad publicity, and indeed just about every large organization from business to charity spends tremendous amount of time and money trying to get noticed by the public. You'd think therefore that it would be a good thing that particle physics gets the press it does. You'd think, but then you see news stories like this, from which we can get the gist by quoting the second paragraph: ...Then it will be time to test one of the most bizarre and revolutionary theories in science. I'm not talking about extra dimensions of space-time, dark matter or even black…

Snowy Decibels

There's a list of books a cultured person is supposed to have read. Its size and composition vary depending on who you ask, but roughly speaking there exists a Western canon containing works by authors with names like Shakespeare and Dostoevsky and Milton and Sophocles. There's something of a Nerd Canon too. The names of the authors of its works are more like Asimov and Feynman. It's a list that's certainly not all science and science fiction, though those are much more strongly represented than in most general lists. To me knowledge no one has ever written such a list up, but it exists…

The Positive Manifold: Reactive Control in Fluid Intelligence?

What neural mechanisms underlie "fluid intelligence," the ability to reason and solve novel problems? This is the question addressed by Gray et al. in Nature Neuroscience. The authors begin by suggesting that fluid intelligence (aka, gF) is related to both attentional control and active maintenance of information in the face of ongoing processing (i.e., working memory). Each of these concepts, in turn, has been associated with the functioning of the lateral prefrontal cortex - a region that has been massively expanded in humans compared to even our closest evolutionary relatives. To…

Travis The Chimp, Humanity versus Chimpanzity, Evolution, and Responsibility

Denyse O'Leary is nattering on over at Uncommon Descent - and several other places - about some sort of connection between "Darwinists" or perhaps "Darwinism" and the recent and tragic case where a pet chimpanzee attacked and mutilated one of the owner's neighbors. A large portion of the various posts seems to revolve around Denyse's love of the tautology "only people are people." The rest seems to consist of an attempt to find some way to blame the attack on the scientific community as a whole, or at least on "Darwinists." Frankly, I'm having an even harder time understanding O'Leary than…

Did the "Marsupial Lion" Climb Trees?

Restoration of the skull of Thylacoleo. From The Ancient Life History of the Earth. Thylacoleo was one strange mammal. A close relative of living koalas, kangaroos, and wombats, the largest species of Thylacoleo were lion-sized carnivores that stalked the Australian continent between 2 million and 45 thousand years ago. Despite its popular nickname "marsupial lion", however, Thylacoleo was quite different from any feline predator. Even though its long forelimbs were tipped with retractable claws its skull more closely resembled that of a koala, with curved incisors set in front of a pair…

Is it sexist to think men are angrier than women?

Earlier today we asked readers to imagine an angry face. Then, in a surprise poll, we asked what gender the face was. So far our results match those of a study led by D. Vaughn Becker: over three-fourths of the responses were "male." In the published study, there was no difference in the response based the respondent's gender. Both men and women are much more likely to think of a male "angry" face than a female one. If we'd asked you to picture a happy face instead of an angry face, the results would switch almost as dramatically in the opposite direction: Most people say happy faces are…

Deep brain stimulation evokes long-lost memories

Canadian surgeons have made a serendipitous discovery. While using deep brain stimulation to try suppressing the appetite of a morbidly obese patient, they inadvertently evoked in the patient vivid autobiographical memories of an event that had taken place more than 30 years previously. They also found that the electrical stimulation improved the patient's performance on associative memory tasks. These unexpected findings raise the possibility that deep brain stimulation could be used to treat patients with Alzheimer's Disease, and the research team is now beginning a small clinical…

What's in the air?

Good question ... what IS in the air? The simple answer is that the air ... the Earth's atmosphere ... is about 78% nitrogen, 21% oxygen, with a tiny amount of some other gases including water vapor. Then, there's dirt. I want to talk a little about the oxygen, one of the other gases (carbon dioxide to be exact), the water vapor, and the dirt. Oxygen The oxygen is one of the most important parts to us because we (and all the other animals) need it to breath. To me, what is most interesting about the oxygen is that in the old days ... before any animals or plants evolved but life…

Early, somewhat controversial hominid walked like an Australopith

The ape human split is a bit of a moving target. In the 1970s and early 1980s, there were geneticists who placed it at very recent (close to 4 million years ago) and palaeoanthropologists, using fossils, who placed it at much earlier. During the 1980s, the ape-human split moved back in time because of the importance of sivapithecus, then later in time when Sivapithecus slipped and fell out of the hominid/hominin (human ancestor) family tree. Meanwhile the geneticists were moving towards a more and more recent split. At one point not too long ago, all the evidence converged with the split…

Phylogeny Friday -- 11 April 2008

Drosophila Are Not Fruit Flies Edition As I have mentioned before, Drosophila are not fruit flies. Tephritids are fruit flies. Drosophila feed on rotting fruit, while true fruit flies feed on fresh fruit. That makes true fruit flies agricultural pests. Drosophila, on the other hand, are connoisseurs of the finer things in life -- wine, beer, cheese, and the like. In addition to rotting fruit, Drosophila also feed on mushrooms and crabs. Yes, crabs. Well, they don't actually feed on the crabs, just like they don't actually feed on the fruit. The flies and their larva are more interested in…

A Universal, One-Shot Flu Vaccine?

A Better Grip: T Cells Strengthen Our Hand against Influenza Clinical Infectious Diseases, 52 (1), 8-9 DOI: 10.1093/cid/ciq018Flu vaccines are important and useful, but also relatively ineffective compared to many other vaccines. Immunity is imperfect, there are many 'strains' of influenza in a given year only some of which are addressed by the available vaccine (though often the most common ones) and one year's vaccine does not provide immunity to subsequent years' influenza because the virus changes so much. Well, actually that's not exactly true: The influenza virus has various…

A contest gets a winner: common creationist claims refuted

Once upon a time, in vague exasperation at a persistent creationist, I opened up two of his questions to the Pharynguloid horde in a contest to see who could answer them most clearly and succinctly. I shouldn't have done this; I'm lazy, and this was too much like grading term papers. Still, there were a lot of good answers, so it was a worthwhile effort. The winner, judged for clarity, brevity, and accuracy, was Calilasseia, an infrequent commenter here who clearly needs to increase his or her frequency. I've sent off an email in hopes of a reply with a mail address, or if Calilasseia notices…

Stochastic training wheels

The idea of stochastic training wheels sounds a bit scary, but I am alluding to the series of posts on stochastic dynamics adapted from chapter 5 of Evolutionary Genetics: Concepts & Case Studies by John Gillespie. Using Gillespie's terminology the posts were: Boundary Process Origination Process Genetic Drift Genetic Draft Random Environment There was also another factor which Gillespie points to, which didn't have a particular section and rather loomed over all the other parameters, and that was Deterministic Selection. Of Gillespie's parameters only one is highly dependent on the…

Evolution of Rape Avoidance Just-So Stories Are Stupid

That's not very civil of me, but it is honest. Having said that, behavior is obviously based in biology, and it does stand to reason that some behaviors will have been influenced by natural selection. Admittedly, I'm biased against evolutionary psychology: I think, in general, the claims made are far too strong and the confounding variables inadequately controlled (in my really snarky moments, I think evol psych is a justification for middle-aged faculty to sleep with their younger graduate students). A recent Slate article which asks "Have women evolved to protect themselves from…

Attack of the flying steamer ducks

I like ducks, and I particularly like steamer ducks. Again, here we revisit some Tet Zoo ver 1 text that was originally published in 2006 as part of the Ten Birds Meme. The most widely distributed of the four Tachyeres species*, the Flying steamer duck T. patachonicus inhabits both the fresh and marine waters of the Falklands and southern Patagonia and Tierra del Fuego. While all other steamer-ducks are flightless, T. patachonicus is (obviously) not, and in contrast to its flightless relatives it has proportionally bigger pectoral muscles and lower wing loadings. But what makes the species…

New Type of Antibiotics Designed Not to Cause Resistance

If you work in infectious diseases in a hospital -- or frankly if you work anywhere in a hospital -- the emergence of antibiotic resistant bacteria is a serious problem. You have to be constantly aware of what the right drug is to prescribe to ensure its maximum effectiveness, and -- though rare -- there are some bacterial infections for which we have no good drugs. This is why I was very intrigued about researchers trying to design antibiotics that would not create resistant bacteria: Vern L. Schramm, Ph.D., professor and Ruth Merns Chair of Biochemistry at Einstein and senior author of the…

Keeping 'em alive

One of the frequent complaints I hear about real medicine is that it is dangerous. Of course, it's true---so is riding in a train, but it sure beats walking. And that's the danger of this particular fallacy---yes, medicine is a sharp tool, but it's also an effective tool, so we must use it properly. And this is where the tools of evidence- and science-based medicine can give us a hand. The potential harms of modern medicine must be approached carefully. If they are ignored or approached in an ineffective way, we'll miss an opportunity to save lives. This comment is typical of the type of…

Species description: Creationists

I was bemoaning to Paul Griffiths and Sahotra Sarkar, admittedly over a beer, that unlike them (they are both birdwatchers), I lacked a special organism I could be expert about. This is a grievous fault in a philosopher of biology, so we wondered what I could choose as my "target organisms". Sahotra suggested I name and describe creationists (well, actually he suggested he would, but I'm stealing this from him) as a species. It's important to do this, so that when we describe the behavior of these creatures (pun intended) in the wild, we know exactly what we are discussing. One wouldn't want…

Objects changing right before our eyes -- and still not being seen

Take a look at the short movie I've linked below (Click on the picture to play. QuickTime required). The movie shows a virtual gripping device (two red balls) lifting rectangular objects and placing them on a conveyor belt. Do you notice anything unusual happening as the objects are being moved? This is a recording of the image seen by a volunteer using a virtual-reality headset and two force-feedback devices to simulate moving objects by picking them up with a thumb and index finger. The force-feedback devices offer resistance so that the volunteer feels as if he is lifting real objects…

Duncan and Maltz letter to the AEI

Keiran Healy observes that the U Chicago Federalist Society acted with integrity when Lott libeled Donohue. In the comments, Michael Maltz posts the letter that he sent with Dudley Duncan to the AEI about Lott and the reply they received: October 21, 2003 Christopher DeMuth President American Enterprise Institute 1150 Seventeenth Street, N.W. Washington, DC 20036 Dear Mr. DeMuth: As you are doubtless aware, a number of commentators have recommended that AEI initiate an inquiry into allegations of unprofessional and unethical behavior by John R. Lott, Jr., an AEI Resident Scholar. They…

The science of dreaming

Most people don't know that Sigmund Freud was a frustrated neurologist. Before he abandoned himself to abstraction, the father of psychoanalysis was a practicing physician, intent on developing "a neural model of behavior." (Kandel Interview) But Freud found neuroscience too blunt a tool, in the early twentieth century, to serve his purposes. If brain science had been further along at the turn of the century, we might have been spared the Oedipus Complex and the concept of penis envy. But we may also have missed out on his theory that dreams are a form of wish fulfillment--a hypothesis that…

Korean genetic relationships

There's a new paper, The Peopling of Korea Revealed by Analyses of Mitochondrial DNA and Y-Chromosomal Markers: Methodology and Results We analyzed mitochondrial DNA...sequence variation in the hypervariable segments I and II...and haplogroup-specific mutations in coding regions in 445 individuals from seven east Asian populations...In addition, published mtDNA haplogroup data...mtDNA HVS-I sequences...Y chromosome haplogroup data...and Y chromosome STR da...were analyzed to elucidate the genetic structure of East Asian populations. All the mtDNA profiles studied here were classified into…

Bottled Water Sales: The Shocking Reality

The numbers are in for 2012, and they are shocking. The Beverage Marketing Corporation, which tracks sales and consumption of beverages, is reporting that sales of bottled water grew nearly 7 percent between 2011 and 2012, with consumption reaching a staggering 30.8 gallons per person. And since I (and some of you) consume almost zero bottled water every year, there are people out there drinking far more than the average. Thirty-six years ago, this industry didn’t exist. Americans drank fewer than two gallons of bottled water per year, and almost all of that was in the form of water from big…

Fisking William Kristol on Gay Marriage

The more I read from conservatives and their arguments against gay marriage, the more I'm convinced that there simply isn't any there there. The latest is from William Kristol, who, along with Joseph Bottum, writes this article in the upcoming issue of the Weekly Standard. The article is almost purely rhetorical, with virtually nothing of substance offered in terms of legal arguments. It begins: In an act of astonishing self-righteousness and self-congratulation, the Massachusetts Supreme Judicial Court has forced the question of marriage upon the entire United States. Okay....were they wrong…

Science and Religion, Again

In a post from 2012, I wrote the following as part of a discussion about reconciling science and religion: Too often the defender of reconciliation acts as though his job is done as soon as he has tossed off a logically possible scenario that includes both God and evolution. This was specifically in response to an interview with philosopher Elliott Sober, in which he breathlessly reported his finding that science could not absolutely rule out the possibility that God was guiding the mutations in the course of evolution. Adorably, he seemed to think this represented a genuine contribution…

The Twitter Creationist Time Machine!

It's reassuring to know that it's not just other atheists who hate me, but that I also still piss off the creationists. In addition to the mob of atheist dudebros howling at my door, there has been a recent resurgence of creationist loonietarianism in my email. It seems to have been triggered by a Seventh Day Adventist pastor, Doug Batchelor. SDAs are really among the battiest of the batty; their young earth creationism isn't simply a product of ignorance and gullibility, but is literally enforced doctrine. They had a nineteenth century prophetess, Ellen White, who insisted that she had seen…

Orbits, Periodic Orbits, and Dense Orbits - Oh My!

Another one of the fundamental properties of a chaotic system is dense periodic orbits. It's a bit of an odd one: a chaotic system doesn't have to have periodic orbits at all. But if it does, then they have to be dense. The dense periodic orbit rule is, in many ways, very similar to the sensitivity to initial conditions. But personally, I find it rather more interesting a way of describing key concept. The idea is, when you've got a dense periodic orbit, it's an odd thing. It's a repeating system, which will cycle through the same behavior, over and over again. But when you look at a state…

Parasites keep red tides at bay

Over the past decade, some coastal waters have started turning red with alarming frequency. The cause is not some Biblical plague, but dense concentrations of microscopic algae called dinoflagellates. Red tides can often contain more than a million of these cells in a mere millilitre of water. Many are harmless and essential parts of the ocean environment, but others produce toxins that can kill local wildlife and risk the health of humans who eat their poisoned flesh. These "harmful algal blooms" are more common in warm waters that mix poorly and are unusually rich in nutrients. Their…

"Horned" crocodile may have preyed upon prehistoric humans

A Cuban crocodile (Crocodylus rhombifer), photographed at the National Zoo in Washington, DC. No one knew what happened to William Olson. At about three in the afternoon on April 13, 1966 he had been swimming with his friends from the Peace Corps in the part of the Baro river that ran through Gambela, Ethiopia when he suddenly disappeared. The last person to remember seeing him was hunter Karl Luthy. One moment Olson was standing in the river, pressing his body against the current, and the next he was gone. Luthy could not be sure, but he was almost certain that Olson had been taken by a…

A date with Lucy (and Ida, too)

Against all hope I brought my camera along with me. Special exhibitions do not usually let you take photos, and soon after I arrived at the Discovery Times Square Exhibition with Amanda and her boyfriend J I was forced to hand over all my equipment. No cameras, no cell phones, no food, keep your hands and arms inside the vehicle at all times, &c. Despite my disappointment, however, it was hard to be sad. I was going to see "Lucy", perhaps the most famous hominin fossil ever discovered, and the B-slab of "Ida", a much older fossil primate that kept me rather busy during the past month. I…

Compulsive Gambling a possible side-effect of Restless Leg Syndrome drugs

Restless Legs Syndrome is a neurological disorder, in spite of what you might think from the ridiculous ads on television. RLS is a syndrome where the individual has weird sensations in their legs while they are trying to relax. These sensations can be just unpleasant, or they can be quite painful. The result is that the individual has trouble sleeping -- leading to a marked reduction in their quality of life and ability to function. RLS is treated with drugs similar to Parkinson's drugs -- drugs that function as dopamine agonists. It is known that a rare side effect of Parkinson's…

The Trouble with Magic Bullets

Antibodies are often thought of as magic bullets, and as far as bullets go, they are about as magic as you can get. Antibodies are proteins that are manufactured by specialized "B-cells," and their main feature is that they stick to things. At first glance, biochemical stickiness does not seem all that magical; there are innumerable examples of proteins that have evolved to interact with one another or with other types of molecules. But while natural selection can take millions of years to refine an interaction, your body can mount an immune response and generate antibodies against almost any…

New cells in the adult brain migrate long distances by crawling along blood vessels

The journey undertaken by newly generated neurons in the adult brain is like the cellular equivalent of the arduous upstream migration of salmon returning to the rivers in which they were hatched. Soon after they are born in the subventricular zone near the back of the brain, these cells migrate to the front-most tip of of the olfactory bulb. This is the furthest point from their birth place, and they traverse two-thirds of the length of the brain to get there. The first leg of this epic journey - the departure of the newborn cells from the subventricular zone - involves some of the…

All work and no play

make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work and no play make Evil a dull monkey. All work…

The USA is still yielding lots of new extant tetrapod species

The naming of new amphibian species is a fairly routine thing. This doesn't mean that - despite the global amphibian crisis - amphibians are actually ok and that we can stop worrying; it means that we haven't been paying enough attention, and indeed many of the species that are being named anew are endangered, or threatened, or with tiny ranges. The current edition of Journal of Zoology includes the description of a new plethodontid salamander (aka lungless salamander): the Patch-nosed salamander Urspelerpes brucei Camp et al., 2009. The big deal about this entirely new species is that it's…

Darwin Crossing The Atlantic

 Behold this humble passage by Darwin, which is what immediately follows his discussion of the octopus. This passage is a touchstone to several important aspects of what Darwin was doing and thinking, and is a poignant link to what Darwin did not know: Repost with slight modifications ST. PAUL'S ROCKS.--In crossing the Atlantic we hove to, during the morning of February 16th, close to the island of St. Paul. Ah, sorry to interrupt. Saint Paul's Rocks are in the Atlantic roughly half way between South America and Africa. That geographical information should give you a hint of why…

Region & race; opinions & values

In the post below I combined some of the Census Regions for reasons of sample size. But I decided to do this again without combining, but removing some of the questions because of small sample sizes. Again, I also limited the sample to whites between 1998-2008. But, I added another category: blacks. Michael Lind said: Drum's creepy bigotry becomes clear when other groups are substituted: "There are, needless to say, plenty of individual blacks who are wholly admirable. But taken as a whole, black culture is [redacted]. Barack Obama can pretty it up all he wants, but it's a [redacted]." Or…

Which nations support open borders...Vietnam...and more

The World Values Survey has a question about immigration policy with four options: - Let anyone come - As long as jobs available - Strict limits - Prohibit people from coming I used WVS 2005-2008 from 57 countries first. Then I filled out the countries with the Four-wave Aggregate of the Values Studies, the combined file of the four waves carried out by both the EVS and WVS. I bring this up because there are discrepancies between the two where there are duplications. Again Vietnam is at the top of the list. Perhaps Will Wilkson should have picked another country to trade in his American…

Are parrots actually pigeons?

Historically, an apparent absence of transitional forms has made it difficult to reconstruct the evolutionary affinities of the different modern avian 'orders'. As you'll know if you've been keeping up with the results of the various big molecular and morphological analyses - and who hasn't - the avian cladogram is gradually coming together, though areas of debate and disagreement remain. One of the most vexing areas has been the origin of the parrots, or psittaciforms. An idea frequently mooted in the ornithological literature is that parrots are close kin of pigeons and doves - the…

Ask a Scienceblogger: Sensation and Perception Basics

There are some great questions coming in to Ask a Scienceblogger! If you (or your kids?) have a question you want answered by a scienceblogger drop by Page 3.14 (the blog of the SB overlordz) and leave your question in the comments on this post. Tyler asked: It's said that the left hemisphere of the brain controls the right half of the body and vice versa. Does this apply to the processing of audio and visual stimulus of the ears and eyes as well? Does the left half of the brain process what the right eye sees and vice versa? There's actual a few questions in here, so let's break this apart…

At last, the rhinogradentians (part I)

I am always surprised when I meet zoologists who aren't familiar with Harald Stumpke's* famous 1957 book Bau und Leben der Rhinogradentia, a volume translated into English by Leigh Chadwick in 1967 as The Snouters: Form and Life of the Rhinogrades (and referred to from hereon as 'Stumpke 1967'). For the few who don't know, this legendary text discusses in marvellous detail the biology, lifestyle and evolution of the snouters (aka rhinogrades or rhinogradentians), a bizarre and unique group of small mammals originally thought endemic to the south Pacific Hi-yi-yi archipelago, an island group…