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Showing posts from January, 2010

Feathered dinosaur developments

Recently, three papers have been published on the subject of feathered dinosaurs and the evolutionary origin of birds. In the first, Alexander et al. made a model of Microraptor to test its gliding capability. Microraptor is one of those weird four-winged feathered dinosaurs. The paper is interesting, but the videos are really fun to watch. What I'd like to know now is what advantage does four wings have over two? Or is it just another way to get from here to there?

In a paper published online in Nature, Zhang et al. looked at fossilized melanosomes in feathers of both birds and feathered dinosaurs. The headlines about this paper that I've seen are treating this as if Zhang et al. have resolved what color these critters were. The far more significant discovery is summarized in the abstract of their paper:
Here we report that melanosomes (colour-bearing organelles) are not only preserved in the pennaceous feathers of early birds, but also in an identical manner in integume…

Chimp and human Y chromosomes radically different?

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Very interesting article in Nature today:

Hughes et al. 2010. Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content. Nature 463:536-539.

From the abstract:
Here we finished sequencing of the male-specific region of the Y chromosome (MSY) in our closest living relative, the chimpanzee, achieving levels of accuracy and completion previously reached for the human MSY. By comparing the MSYs of the two species we show that they differ radically in sequence structure and gene content, indicating rapid evolution during the past 6 million years.Wow. "Remarkably divergent?" "Differ radically?" That's impressive. Given creationists' general obsession with the similarity of the chimp and human genomes, I expect this report will become a hot topic on creationist websites and in upcoming issues of creationist journals.

But how radical is radical? Well... pretty radical. The diagram at the top of this post is from Figure 1 in the Hug…

Evolution and health care

I often hear folks tell me that evolution doesn't have anything to do with real science, like for example medicine. I sympathize with that. In my own experience, many folks in biomedical research know little about evolution. On the other hand, general ignorance of evolution does not mean that evolutionary theory cannot inform medical research. Witness the latest supplementary issue of PNAS, dedicated to an "Evolution in Health and Medicine Sackler Colloquium." The papers appear to be open access, so enjoy. A few that might be of interest to creation biologists (or at least of interest to me):

Holmes. 2010. The comparative genomics of viral emergence. PNAS 107:1742-1746.

Carneiro and Hartl. 2010. Adaptive landscapes and protein evolution. PNAS 107:1747-1751.

Nesse et al. 2010. Making evolutionary biology a basic science for medicine. PNAS 107:1800-1807.

Speaking in England

I'm off to England in March, where I'll be speaking at a variety of venues in southern England. Check out all the details of my visit at Paul Garner's blog:

Todd Wood: March speaking tour of the UK

That is all. Have a nice weekend!

More genomes than I know what to do with

OK, I give up. I've been going over the maize genome in my spare time, which is why I haven't blogged about it since I don't really have any spare time lately. Then I saw three parasitoid wasp genomes in Science, and I thought that'd be cool to talk about. Then the soybean genome was published in Nature, and this week, it's the panda genome also in Nature. So I give up. I'm still holding out hope that I'll be able to do something substantive for the maize genome, but for the others, I'm just going to give a brief rundown.

Parasitoid wasps lay their eggs on other critters, and when they hatch, the young gradually consume and eventually kill their hosts. If I recall correctly, this was one of the sticking points that Darwin mentioned: How could natural theologians argue for a loving God when such unpleasant things like parasitoids exist? Three species of the parasitoid wasp genus Nasonia now have their genomes published. What do we find? About 17,…

Deleterious mutation rates in humans

Interesting article in yesterday's PNAS by Michael Lynch. He tried to estimate the mutation rate in humans and its consequence on human fitness and health. His conclusion?
Finally, a consideration of the long-term consequences of current human behavior for deleterious-mutation accumulation leads to the conclusion that a substantial reduction in human fitness can be expected over the next few centuries in industrialized societies unless novel means of genetic intervention are developed.
Fascinating.

Lynch. 2010. Rate, molecular spectrum, and consequences of human mutation. PNAS 107:961-968.

Just another day in the museum...

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Nothing out of the ordinary here.

HDHPNPR

So the platypus is weird, right? It's a mammal, but it lays eggs. It secrets milk, but it doesn't have any nipples. It's got that big duck-looking beak, and for those really in the know, it's got a cloaca, a single opening for excretion and reproduction. It's also one of the few venomous mammals, with a spur on its hind legs that can inject venom. It's reportedly quite painful to be stung by a platypus. I wouldn't know. I've never had the privilege.

In a recent issue of the Journal of the American Chemical Society, Kita et al. report on some of the protein toxins present in platypus venom. One in particular is good at causing calcium influx in human nerve cells. They call it venom peptide 1 or heptapeptide 1. It's just seven amino acids (Histidine-Aspartate-Histidine-Proline-Asparagine-Proline-Arginine, abbreviated HDHPNPR), but it's a significant component of the venom and probably packs quite a punch.

What's the creationist applica…

2010 BSG/CGS Call for Abstracts

The 2010 joint conference of the BSG and the Creation Geology Society will be held on the campus of Truett-McConnell College on July 28-30, 2010. We are currently soliciting abstracts on any biological, geological, or related theological/philosophical topic. Abstract guidelines:
Abstracts should not be longer than 700 words. Examples of published abstracts can be found in the Conference Proceedings issues of the Occasional Papers of the BSG (OPBSG). (see Author Guidelines).Abstracts may include references (which are counted in the 700 word limit), but they must be formatted according to the guidelines of the Occasional Papers.Abstracts must include a complete summary of the paper. That includes an introduction, methods, results, and conclusion where appropriate. Abstracts that do not include results or conclusions will be immediately returned for revision.Abstracts should be written in English.Names and affiliations of all authors should be included. Authors working independently sh…

More evidence of genomic modularity

Regular readers know of my affinity for all things related to genome evolution and transposition, partly because of my rejection of the common creationist model of mendelian speciation and partly because my understanding of comparative genomics within baramins demands it. Recent studies are beginning to shed light on theoretical links between stress, transposition, and speciation. Over the holidays, there were two additional papers published on this subject.

First, in a paper in Nature, Horie et al. found evidence of bornavirus insertions in mammalian genomes. This is of interest because prior to this, bornaviruses were not known to integrate into genomes. This observation is related to a point I brought up in my review of Liu and Soper's endogenous retrovirus paper in ARJ, where I wrote,
Another implication would be exploring the origin of other viruses. What about DNA viruses? Could they ultimately originate as escaped genomic elements from other critters? Do we know of any ot…

Linnaeus as a second Adam

My assistant came into my office the other day and said, "You're reading Zygon?" I said, "Yes, and it's actually an interesting article, too!" I admit it: Zygon baffles me. Zygon bills itself as a "Journal of Religion & Science," which in theory is something that could be quite helpful. Indeed, they often have comprehensible articles on topics that I just don't care all that much about, but every 200+ page issue is usually choked with articles that come across as pretentious, postmodern blather. Maybe I'm just out of the loop, but I doubt it.

In any event, since one of our goals at CORE is to archive information related to creation/evolution and religion/science, I am a member of the Institute on Religion in an Age of Science, which includes a subscription to Zygon. I skim the issues and stick them on the shelf, but finally I found an article that was not only readable and interesting but also helpful! I'm still recovering fr…

Dawkins, giraffes, and knowing God

Paul Garner just put up a new post on the laryngeal nerve of the giraffe. Dawkins has been using this example as evidence of evolution, but Paul says it could be explained by intrabaraminic diversification. You should read it; it's a good write-up. It should be noted that the laryngeal nerve takes an odd route in all mammals, but as Paul says, "the emphasis upon the giraffe means that that point tends to get rather lost."

A few of the numerous comments on that post are sort of interesting. (I'm so glad I don't deal with comments here!) A few points to note:

Do I think it's plausible that horses would travel around the world in 90 years? No, of course not. We're not talking about just migration, we're talking about dispersal. Is it plausible for a very small species of horse to disperse transcontinentally in less than a century? I don't see why not.

Saying that "I asked Todd Wood about these intermediate forms a while ago ... and he admitt…

Random bits #6

It snowed again here in east Tennessee. Twice in one winter. That's unusual. While I wait for the sun to come up so I can decide when I'm going to work, here's another installment of random articles that struck my fancy.

First up, the Zoological Journal of the Linnean Society has an article by Fitzgerald on the fossil whale Mammalodon. It was brought to my attention by the ScienceDaily headline "Australian Fossil Unlocks Secrets to the Origin of Whales", which might lead one to believe that it was another intermediate form between land mammals and whales. It's not. Mammalodon is just a funny-looking toothed mysticete, which is a kind of intermediate. Living whales can be divided into toothed whales (odontocetes) and baleen whales (mysticetes). The fossil record shows that mysticetes with teeth actually existed in the past, and Mammalodon is one of them. My own research on toothed mysticetes implies that they aren't in the same baramin as modern my…

fossil tracks

OK, the timing on this one is weird. The latest issue of Answers magazine has a short piece by Kurt Wise on trilobite tracks that occur in layers beneath the earliest trilobite fossils (see p. 48). "Why would dozens of feet of rock have tracks but not the animals that made them?" asks Wise. He proposes that the Flood uniquely solves this dilemma:
What if, when the "fountains of the great deep were broken up" (Genesis 7:11), the spreading waters surprised the trilobites living on the ocean bottom? As the water became muddy, trilobites scurried about in terror, leaving their tracks behind them. Then as a layer of mud covered their tracks, they climbed through the mud and left tracks on the next layer - repeating this process until they finally succumbed in exhaustion and were themselves buried and preserved.Now the latest issue of Nature has an article by Nied┼║wiedzki et al. titled "Tetrapod trackways from the early Middle Devonian period of Poland." T…

Acts & Facts & Answers

I'm back from my holiday travels, and what a time I had! It's always good to get away and get refreshed for the new year. I thought I'd kick things off by drawing your attention to some interesting items in recent creationist publications.

First, the latest issue of Answers magazine is themed around fossils. As usual, they've got actual experts writing about their own fields. Marcus Ross and Kurt Wise have several articles on various paleontological topics. I was also pleased with the coverage of the dinosaur dig at Hanson Research Station on pp. 56-59 by John Upchurch. It's so encouraging to see outstanding creationist research being celebrated and valued. I hope it continues.

Also delightful - and surprisingly pointed - was Andrew Snelling's article "Order in the Fossil Record" (pp. 64-68). Andrew tackles head-on the claims that the geologic column is a false, evolutionary, uninformitarian idea imposed on layers of rock that do not support it…