evolution
pharyngula | January 30, 2007Zimmer describes some of the more recent work on Flores Man — people are still arguing over whether the fossil is of a peculiarly abnormal human with microcephaly, or whether there was a species of 'miniaturized' Homo living on the islands of the Pacific. Trying to establish common characteristics of microcephalics is an interesting project, but it doesn't answer the question. We need more fossils! Among the good news Carl mentions is the report that more excavations will be underway this year.
mikethemadbiologist | January 29, 2007I recently posted about creationists who want their 'biology' courses to be taken seriously by universities. Josh takes to task a libertarian who states "if we chose to mandate what is taught about human origins, and we are true democrats, we should mandate equal time for creationism and evolution." So, I found on the internets a description of Biology for Christian Schools, a creationist textbook, written by the textbook's authors.
Creationism should never be viewed in the abstract, but as the mindless indoctrination that it is. Hold your breath and dive in; the passage destroys the…
jrosenhouse | January 29, 2007The stereotype about acedmics living in ivory towers does have a germ of truth to it. For the latest example, have a look at biologist J. Scott Turner's take on the ID situation. He was writing in The Chronicle of Higher Education.
He begins:
I'd never had a heckler before. Usually, when I'm asked to give a talk, I discuss my research on termites and the remarkable structures they build. Usually, I'm glad just to have an audience. x But what I'd learned from termites had got me thinking about broader issues, among them the question of design in biology: Why are living things built so well…
oracknows | January 28, 2007I haven't seen a Broadway play in quite a while now, but it may be time for that to change. In the New York Times, I came across an ad for a revival of Jerome Lawrence and Robert E. Lee´s 1955 courtroom drama Inherit the Wind:
This revival of the play stars two great actors, Brian Dennehy as Matthew Harrison Brady and Christopher Plummer as Henry Drummond. For those who aren't familiar with the story, Inherit the Wind is a heavily fictionalized account of the Scopes Monkey Trial of 1925, not to mention a great American play. Previews begin March 19, and the play opens on April 12. I think I…
mikethemadbiologist | January 27, 2007Sara Robinson raises an interesting solution to "end the Intelligent Design fiasco", one that has been discussed here at ScienceBlogs before. Her suggestion is to have universities declare: "Teach what you like, it's all fine with us. But if you put ID in your science courses, we will not accept those courses as adequate for admission to our campus."
I think there's a legitimate argument here: if your religious views make it impossible to accept multiple lines of evidence supporting a well-documented theory, then, yes, you should be discriminated against, in that you are not remotely…
jrosenhouse | January 25, 2007The current issue of Nature features this interesting essay by Nigel Goldenfeld and Carl Woese. The essay's point is that recent discoveries about genomic interactions among microbes, particularly the phenomenon of horizontal gene transfer (HGT), is forcing us to reevaluate certain basic concepts in biology. They write:
One of the most fundamental patterns of scientific discovery is the revolution in thought that accompanies a new body of data. Satellite-based astronomy has, during the past decade, overthrown our most cherished ideas of cosmology, especially those relating to the size,…
clock | January 25, 2007The latest re-post of my BIO101 lecture notes (this one originally from June 05, 2006). I know I will have to rewrite everything about the Three Domain Hypothesis, but you also tell me if I got other stuff wrong or if this can be in some way improved for the classroom use.
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BIO101 - Bora Zivkovic - Lecture 4, Part 3
In the first two parts of this lecture we tackled the Origin of Life and Biological Diversity and the mechanisms of the Evolution of Biological Diversity. Now, we'll take a look at what those mechanisms have produced so far - the…
jlynch | January 24, 2007Darren Naish ("Tetrapod Zoology") has joined our merry band. Wander over, say "Hi", and learn about the evolution of vampires.
evolvingthoughts | January 24, 2007
Tetrapod Zoology, which has been one of my favourite blogs for some time now, has finally moved into Da House! It will get fine tuned, as things go on, I'm sure, but the look and feel are secondary to the wonderful content. Go find out about blood-eating birds.
clock | January 24, 2007Most of our anti-Creationist battles are over efforts to infuse Christian religion into K-12 education. One common battlefield is the courtroom where our side has (so far, until/unless the benches get filled with more clones of Priscilla Owen) won. But another place where we can stop them is the college admission office.
Sara Robinson of the Orcinus blog (which everybody should read daily) revisits, in more detail than I ever saw on any science blogs at the time this first started, the legal battle between the University of California and the Calvary Chapel Christian School over what…
grrlscientist | January 24, 2007
Titanis Walleri, Terror bird.
artist's rendering.
Image: University of Florida.
University of Florida paleontologist Bruce MacFadden said his team has determined that a prehistoric 7 foot tall flightless "terror bird," Titanis walleri, arrived in North America from South America long before a land bridge connected the two continents. The bird apparently island hopped to North America on islands that make up the mountains that now form mountains on the isthmus of Panama.
"It was previously thought that Titanis immigrated to Texas across the Panamanian land bridge that formed about 3 million…
mikethemadbiologist | January 24, 2007A while ago, Bora referred to a short article about David Sloan Wilson, whose research program examines group selection (among other things). Any discussion of group selection is almost always contentious, largely because there is a fundamental confusion (or conflation) of two different phenomena: the evolution of groups and selection among groups (i.e., group selection).
Evolution of groups is a fascinating and fundamental issue in biology, whether it be the evolution of multicellular organisms from single cell organisms, or the evolution of behaviors that create coordinate group behavior…
grrlscientist | January 24, 2007A paleontological treasure trove of fossils was discovered recently in a cave in the Nullarbor Plain in southern Australia. This discovery includes mammals, birds, reptiles and a marsupial lion, Thylacoleo carnifex (pictured), and 23 species of kangaroo, including eight of which are new to science. These fossils date back to between 400,000-800,000 years ago.
The creatures apparently fell to their deaths through openings in the dusty surface of the plain that periodically opened and closed over millennia.
"Sitting in the darkness next to this skeleton, you really got the sense of the animal…
grrlscientist | January 24, 2007tags: Y chromosome, genetics, Britain, African
A study of the human Y chromosome found that seven men with a rare Yorkshire surname carry a rare genetic signature found only in people of African origin. Researchers Turi King and Mark Jobling from Leicester University found that the men appear to have shared a common ancestor in the 18th Century, but the African DNA lineage they carry could have reached Britain centuries earlier.
This discovery was the result of genetic research that analyzed the relationship between the Y chromosome and surnames. The Y chromosome is normally found only in…
grrlscientist | January 23, 2007tags: Microraptor gui, microraptor, biplane, bird flight, evolution
The ancestors of modern birds are thought to have been small, feathered, dinosaurs, the theropods. One of these small feathered dinosaurs is Microraptor gui, a feathered dromaosaur that lived 125 million years ago in what is now China. According to the evidence, Microraptor gui was one of the earliest gliders. But unlike modern birds, it appears to have utilized four wings, like a biplane, because it had long and asymmetric flight feathers on both its hands and feet.
According to initial interpretations, Microraptor flew…
evolvingthoughts | January 23, 2007
Not Darwin. Not Lamarck. Not the Greeks. A French physicist and mathematician...
Pierre-Louis Moreau de Maupertuis (1678-1759) was an interesting man. He devised what we now know as the principle of least action, and showed that the earth was flattened. Some other things he did, however, changed biology forever.
In 1735, the first edition of Linnaeus' Systema Naturae was published. Linneaus put out at least 13 editions of this in his lifetime, and the famous 10th edition was adopted in the 19th century as the "gold standard" - if Linnaeus named a species, that was its name thereafter…
jlynch | January 22, 2007
Scanning electron photomicrographs of two fossil embryo specimens from the 600-million-year-old Doushantuo Formation in South China.
From EurekaAlert:
A decade ago, Shuhai Xiao, associate professor of geosciences at Virginia Tech, and his colleagues discovered thousands of 600-million-year-old embryo microfossils in the Doushantuo Formation, a fossil site near Weng'an, South China. In 2000, Xiao's team reported the discovery of a tubular coral-like animal that might be a candidate for parenthood.
In the February issue of Geology, the journal of the Geological Society of America, Xiao will…
razib | January 22, 2007My post below, Group selection & the naturalistic fallacy, elicited some interesting comments. First, I mentinoed W.D. Hamilton's allusion to a relationship between fascism & group selection. Here is what he said:
'Liberal' thinkers should realize from the outset that fervent 'belief' in evolution at the group level, and especially any idea that group selection obviates supposedly unnecesssary or non-existent harsh aspects of natural selection, actually starts them at once on a course that heads straight towards Fascist ideology....
(page 385, Defenders of the Truth)
I believe I…
evolvingthoughts | January 22, 2007
Fitness. Of the many concepts of evolution, this is perhaps one of the more widely misunderstood. It comes from the unfortunate slogan written by Herbert Spencer and urged on Darwin by Wallace and others: survival of the fittest. People think it means the strongest, or the most aggressive, and that it means evolutionary theory is a tautology. We'll look at these in a bit. but first, what does it really mean in evolutionary biology?
Fitness is a property of a competing variant in a population. It means that X, whatever it might be biologically, is increasing in its frequency in a population…