Wednesday, March 7, 2012

Gorilla genome and fossil fleas

Just a quick note to alert readers to two interesting items in this week's Nature. First up is the publication of the gorilla genome. Pieces and drafts of this have been available for years, but this is the first (to my recollection) summary of the entire genome project. Scally et al. (the authors) aligned the human, chimp, gorilla, and orangutan genomes and reported a mean difference of 1.37% between human and chimp, 1.75% between human and gorilla, and 3.4% between human and orangutan. No surprises there, although I am quite certain there are probably denials of these results already being written. Scally et al. also reported that
In 30% of the genome, gorilla is closer to human or chimpanzee than the latter are to each other; this is rarer around coding genes, indicating pervasive selection throughout great ape evolution, and has functional consequences in gene expression.
For an evolutionary explanation of this result, I recommend Dennis Venema's essay on Speciation and Incomplete Lineage Sorting. It is not yet clear to me exactly what significance this would have for a creationist model, but I have some research going that should shed some light on that question. Meanwhile, the gorilla genome paper is open access, so you can read it for yourself:

Scally et al. 2012. Insights into hominid evolution from the gorilla genome sequence. Nature 483:169-175.

In other news, Huang et al. report newly discovered Chinese fossils from Jurassic and Cretaceous sediments showing really large fleas with siphoning mouthparts but no powerful, jumping hindlegs. Interesting stuff, and possibly relevant for understanding the origin of these ectoparasites. Check it out (if you have a Nature subscription):

Huang et al. 2012. Diverse transitional giant fleas from the Mesozoic era of China. Nature 483:201–204.

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