evolution
razib | August 5, 2007Update III: John Hawks comments.
Update II: Here is the paper. The abstract:
A common assumption in the evolutionary scenario of the first Eurasian hominin populations is that they all had an African origin. This assumption also seems to apply for the Early and Middle Pleistocene populations, whose presence in Europe has been largely explained by a discontinuous flow of African emigrant waves. Only recently, some voices have speculated about the possibility of Asia being a center of speciation. However, no hard evidence has been presented to support this hypothesis. We present evidence from…
oracknows | August 4, 2007In case you haven't seen it yet...
Sad.
I can't believe Behe is still using the mousetrap analogy for "irreducible complexity" when the very concept has been so thoroughly debunked over the last several years.
oracknows | August 4, 2007I really, really wish the Discovery Institute would stop putting out idiocy like this:
We have blogged in the past about the growing numbers of doctors who are skeptical of Darwinian evolution to explain the complexity of life.
Those numbers are continuing to grow, and conesquently doctors are beginning to organize themselves and reach out to others who hold similar positions. Physicians and Surgeons for Scientific Integrity (PSSI) has for sometime had a website at www.doctorsdoubtingdarwin.com. Recently they have begun using the site to organize and promote conferences about Darwinian…
oracknows | August 3, 2007Michael Behe, that Don Quixote of "intelligent design" who never tires of tilting at windmills of "fatal flaws" in evolutionary theory that he think he's identified, did quite a bit of tilting at HIV in his book.
Watch his blathering taken down by a pre-graduate student named Abbie. It's so good it's been republished at Panda's Thumb.
Enjoy.
evolvingthoughts | August 3, 2007
So I'm home from Ish, and the front part of my brain is giddy and tired while the rest has just shut down. I don't travel well, I'm afraid.
One thing that I came back fired up over are the unfinished projects I have running. So I intend to finish them. They are, in no particular order:
1. Denying that genes have information [heresy #1] Status: Written and needing to be submitted.
2. Denying that functions in biology exist outside models [heresy #2] Status: Written but badly in need of a rewrite.
3. Denying that essentialism ever existed in biology [#3. Four more and I get a free auto…
pharyngula | August 1, 2007Since I was asked what a cnidarian "head" is in reference to this work on multi-headed cnidarians, I'll answer. In short, they don't have one.
Longer answer: the paper in PLoS describes a procedure for generating homeotic mutations in cnidarians by manipulating the expression of Cnox genes in hydrozoans. Knock outs of various cnidarian Hox-like genes and the medusae develop extra manubriae, or the tentacled part at the oral end of the animal, which the authors colloquially call "heads" (and they do usually put the word in quotes). These structures aren't homologous to the things we consider…
loom | July 30, 2007Last update of the day: Tomorrow's New York Times has a profile I wrote about Martin Nowak, a mathematical biologist at Harvard. Nowak uses games to understand how cooperation evolved--whether that cooperation is between people or between cells or between genes. I've written about Nowak in passing before--his work on language evolution turns up in my book Evolution: The Triumph of an Idea, and there's a bit on his research on cancer evolution in an article I wrote last year for in Scientific American. But I was very curious to talk to Nowak and figure out how all these topics fit inside the…
razib | July 30, 2007 Were Neanderthals our enemies or lovers?:
One difficulty in working out how these ancient humans rubbed along is that there is a lack of clear evidence of close encounters. That changed two years ago when a paper was published by Prof Paul Mellars, of Cambridge University, and his student Brad Gravina, suggesting the two kinds of human lived together at Grotte des Fées at Châtelperron in France.
The study was criticised but the Cambridge team published a detailed rebuttal. "The importance of the new paper is that it confirms at least 2,000 years of coexistence/overlap between Neanderthals…
pharyngula | July 30, 2007
People are always arguing about whether primitive apes could have evolved into men, but that one seems obvious to me: of course they did! The resemblances are simply too close, so that questioning it always seems silly. One interesting and more difficult question is how oysters could be related to squid; one's a flat, sessile blob with a hard shell, and the other is a jet-propelled active predator with eyes and tentacles. Any family resemblance is almost completely lost in their long and divergent evolutionary history (although I do notice some unity of flavor among the various molluscs,…
pharyngula | July 26, 2007A few years ago, everyone was in a tizzy over the discovery of Flores Man, curious hominin remains found on an Indonesian island that had a number of astonishing features: they were relatively recent, less than 20,000 years old; they were not modern humans, but of unsettled affinity, with some even arguing that they were like australopithecines; and just as weird, they were tiny, a people only about 3 feet tall with a cranial capacity comparable to a chimpanzee's. This was sensational. Then on top of that, add more controversy with some people claiming that the investigators had it all wrong…
pharyngula | July 25, 2007Feeling pragmatic? Is your focus entirely practical, on what works and what will get the job done? Are you one of those fighters for evolutionary biology who waves away all the theory and the abstractions and the strange experimental manipulations, and thinks the best argument for evolution is the fact that it works and is important? This book, The Evolving World: Evolution in Everyday Life(amzn/b&n/abe/pwll) by David Mindell, does make you sit down and learn a little history and philosophy to start off, but the focus throughout is on the application of evolution to the real world. It…
sporte | July 25, 2007Not content with his recent exploits in human experimentation and cavorting with Plosites in San Francisco, Professor Steve Steve jetted across the country once again, last week, hitting both both Blacksburg, VA and Seattle, WA, and creating pandemonium wherever he went.
And raising the question - how does he get back and forth across the coast so quickly?
Will you find out below? Will you ever find out? Who knows what you'll find out when you see- oh no! what's he doing? Steve! You'll get sunburned! Noooooooo!
Steve! Not in front of photographers!
Professor Steve Steve bears it…
pharyngula | July 24, 2007A correspondent just reminded me of this classic paper from the literature—it's the only contemporary scientific work I know of that managed to combine a discussion of the induction of a tissue by TGF-β and BMP proteins with a discussion of the Hebrew noun tzela to suggest that the book of Genesis wasn't talking about thoracic ribs at all. All us sneering atheist professors who've had to exhibit human skeletons to show the creationists in our classrooms that men are not missing a rib apparently should have been pointing a little lower — where humans are missing a bone.
This comment on the…
razib | July 24, 2007Update II: John Hawks leaves a comment.
Update: Kambiz has much more comment.
Were neandertal and modern human cranial differences produced by natural selection or genetic drift?:
... Here we use a variety of statistical tests founded on explicit predictions from quantitative- and population-genetic theory to show that genetic drift can explain cranial differences between Neandertals and modern humans. These tests are based on thirty-seven standard cranial measurements from a sample of 2524 modern humans from 30 populations and 20 Neandertal fossils. As a further test, we compare our results…
scientificactivist | July 24, 2007If we learned anything from the Atlas of Creation, it's that we can refute any evidence, regardless of how scientifically sound it is, just by putting a red X across it and writing "FALSE". Jeremiah McNichols reflects on this at his blog Think In Pictures... and then he takes it one step further. McNichols is selling merchandise to give you the same powers of refutation as the Atlas's own Harun Yahya. Check it out here. All proceeds go to the American Association for the Advancement of Science (AAAS), so it's for a good cause.
Besides, who wouldn't want to be able to do this?
Evolution…
mikethemadbiologist | July 24, 2007A colleague has told me about some interesting data that people are far less likely to request an antibiotic for a chest cold than for bronchitis even though they're the same thing. With that in mind, here's something from the archives.
One cause of the evolution of antibiotic resistance is the inappropriate use of antibiotics in clinical practice. A recent study concluded that antibiotic therapy did not result in eliminate bronchitis any faster than not using the antibiotic:
A study found that bronchitis sufferers who are otherwise healthy do not get better any faster by taking antibiotics…
razib | July 23, 2007The Mastodon paleogenomics paper is out on PLOS:
We obtained the sequence from a tooth dated to 50,000-130,000 years ago, increasing the specimen age for which such palaeogenomic analyses have been done by almost a complete glacial cycle. Using this sequence, together with mitochondrial genome sequences from two African elephants, two Asian elephants, and two woolly mammoths (all of which have been previously sequenced), we show that mammoths are more closely related to Asian than to African elephants. Moreover, we used a calibration point lying outside the Elephantidae radiation (elephants…
loom | July 23, 2007Last week the world press took note of a fish hauled up off the coast of Zanzibar. (AP, Reuters). Why did they care? Because the animal was one of the most celebrated fish of the sea: it was a coelacanth.
The coelacanth is an ugly, bucket-mouthed creature. At first scientists only knew it from its fossils, the youngest of which was 70 million years old. In 1938, however, a flesh-and-blood coelacanth was dredged up near East London, South Africa. The five-foot long beast had many of the hallmarks of fossil coelacanths, such as hollow spines in their vertebrae, peculiar lobe-shaped fins, and a…
pharyngula | July 23, 2007The first review of my talk yesterday is in! Too bad it is from somebody who wasn't there and who is a world-class fool. Yes, it's Michael Egnor again, and he's got a lengthy post up with the pretext of giving me advice on future talks, but is really an attempt to preempt my arguments and chide me for my crazy materialist position. He doesn't even come close to any of my arguments, and he makes false assumptions all over the place about what I and the audience think. I'm used to straw men from creationists, but this is ridiculous.
Here's what I actually said at the talk.
The first half was…
mikethemadbiologist | July 21, 2007Again. ScienceBlogling razib discusses some noises various biologists are making about levels of selection (I've touched on this topic before in the context of group selection). Sweet Baby Intelligent Designer, save us from this madness.
I've been through this before--hell, I've even published stuff related to the topic**, and there isn't much there except for intellectual masturbationuninteresting and bad philosophy. If it doesn't provide me with testable hypotheses and the conceptual tools to do so, it's just not useful. That's what happened the last go around with this in the late 80s…