01 April 2011

34th Carnival of Evolution

Welcome to the 34th Edition (1 April 2011) of the Carnival of Evolution, and welcome to Quintessence of Dust. It's nice to be hosting this fine carnival, and to see that it's still going strong.

I've organized the carnival under some chapter and section headings that I got from some old Victorian's magnum opus, but I think you'll find the topics require no further creative embellishment.


On the Imperfection of the Geological Record

Before you read anything else, check out this major new fossil find, discussed over at Panda's Thumb. This one's really appropriate for today. Tomorrow, not so much.

Miscellaneous Objections to the Theory of Natural Selection

Larry Moran over at Sandwalk has begun a series explaining, again, why creationist writings on so-called "junk DNA" are misleading (deliberately so, in my view). Larry takes apart a recent "inverview" of Jonathan Wells on the subject of Wells' forthcoming book, which Larry calls "the upcoming train wreck." Train wrecks, of course, are often caused by human error. This is not the case with Wells' works of propaganda. Ick. Anyway, keep tabs on Larry's series, called "Junk & Jonathan."

Another favorite subject among ID creationists is the vague notion of "Complex Specified Information." Vacuous drivel? Largely yes, but I think that in some sense it's a useful concept. Joe Felsenstein, in a guest post ("Uncommon Dissent") at Panda's Thumb, explains why he thinks so, too. Further antidotes to creationism can be found at Playing Chess with Pigeons; Troy answers the silly question "Does being the 'fittest' mean eliminating the less fit?" The cartoon is pretty funny.

At BioLogos, you'll find some seriously smart scientists (who happen to be Christians) working hard to dispel ID myths. Dennis Venema is a friend of mine and a superb science writer, and he's in the midst of a series on "Evolution and the Origin of Biological Information." In "Part 2: E. Coli vs. ID" he discusses Richard Lenski's work in the context of ID misinformation. Go.

Instinct

At Epiphenom, Tom Rees explores kin selection and hypotheses concerning altruism and even religious behavior. He discusses a recent article on "Sixteen common misconceptions about the evolution of cooperation in humans" in a post called "The evolution of nice." It was kind of him to do that for us. At Pleiotropy, Bjørn is unimpressed by a recent paper on a similar subject. Writing on "The trouble over inclusive fitness theory and eusociality," he expresses agnosticism regarding kin selection in the evolution of eusociality. I share his discomfort with projects that mix science and "theology," even though I think I qualify as an "infamous accommodationist."

Organs of Extreme Perfection

The Department of Systems Biology at Harvard Medical School runs a cool blog called "It Takes 30." (And yes, they explain the strange name.) One great recent post tackled the interesting question of how chemotaxis might have evolved in bacteria. Chemotaxis is simply movement toward a chemical attractant, sort of like following the smell of brownies. Because it involves two main components – sensing the attractant and moving through space – it presents one of those chicken-and-egg problems that creationists love to crow about. The post summarizes a fascinating new paper which concludes that motility arose before chemical attraction, and suggests that this early motility would have been random (i.e., undirected) but strongly beneficial. An excellent post, earning bonus points for a sly title: "The random walk of evolution."

Where, oh where have all the stromatolites gone? I won't tell you what they are, or where they've gone, or even why you should care. Greg Laden takes care of all of that, with some excellent photos. Key words: biofilms and snails. Seriously, I won't tell you anything more. Read about Lester Park Stromatolites at Greg's place. And at Denim and Tweed, Jeremy discusses recent work showing the cascading effects of bird near-extinction on plant communities: think pollination and co-evolution. Jeremy's blog is full of similarly great stuff.

Organs of Small Importance

Yoda said "size matters not," but I'm told that women often claim otherwise. If you think I'm being witty as I introduce a post on, say, Devonian megafauna, guess again. Human penises are the subject of an extensively-documented post at Observations of a Nerd, where Christie surrenders to her "inner scientist" and asks the one burning question we all secretly wish someone would answer: "does penis size even matter from an evolutionary perspective?!" The map that inspired her quest is fascinating. It's a great post, called (of course) "Is Bigger Really Better?"

Variation under Nature

Okay, so what about brains? Does size matter in that department? Zen Faulkes at NeuroDojo reviews (critically) some recent studies of the importance of brain size in behavioral complexity, studies done in orb-weaver spiders, which make cool webs but vary in size over three orders of magnitude. "Oh, what a tangled web we weave"... because of small brains?"

Don't like spiders? Ah, then maybe you'll prefer Carl Zimmer's interesting tale about a certain kind of animal with saliva that has yielded biomedical bounty for decades. The animals are pit vipers, their saliva is venom, and the stuff you can get from that venom will amaze you. Gene duplication, alternative splicing, anticoagulants... oh yeah. Collecting the samples looks like fun, too. It's "How a pit viper saved millions of lives" and it's only at The Loom. If you'd prefer worms, go to Genome Engineering to read a little about "The genetics of wriggliness." But come on. Don't be a wuss. Check out the vipers, too.

Struggle for Existence

Now here's a remarkable fact: "of the hundreds of disease-causing microbes or pathogens that we know of, none are archaea." That's a quote from "Why are there no (or almost no) disease-causing Archaea?" The post at Byte Size Biology discusses a recent paper that offers a potential explanation. A nice bonus: one of the authors of the post appears in the comments.

Natural Selection; or the Survival of the Fittest

"Everything's just the same, unless it isn't." Is evolution about change? See The Mermaid's Tale for a thoughtful discussion of concepts of stasis, change and drift.

Michael Scott Long provides a brief summary of some new work that suggests that dispersal of individual organisms as a significant evolutionary influence, alongside natural selection (for example), in his post on Cumulative Spatial Sorting.

Recapitulation and Conclusion

You HAVE to check out some of the delightful posters that have been created for Darwin Day at the Essig Museum of Entomology at UC Berkeley. They're included in "Evilution" at The Dispersal of Darwin, and created by Ainsley Seago, a "beetle biologist" according to Michael. My favorite is over on the right.

Thanks for attending our carnival. Next month's edition will appear on or about 1 May at Lab Rat. See you there, and drop us a line if you'd like to host in June.

No comments: