A large metazoan phylogenetic analysis published by Dunn et al. last spring sparked a great deal of attention and seemed to both support some long-held beliefs about the evolution of animals, but also interestingly placed ctenophores at the base of the tree. Now, another paper, this one in PLoS Biology and featuring two of my colleagues at the AMNH as authors, sheds some interesting new light on this huge and important question. Central to the new analysis is the inclusion of a really bizarre and shockingly simple metazoan - Trichoplax, an amoeba-shaped creature made up of just three layers of cells without any internal structures at all, which glides along and chomps on bacteria. The inclusion of this taxon, along with a massive analysis that included nuclear and mitochondrial sequences, morphology, secondary structure data, and evo-devo characters now splits animals into two broad clades: the bilateria, which include ecdysozoans, lophotrochozoans, and deuterostomians) and then the diploblasts, which are the cnidarians and ctenophores, the porifera and the placozoans, represented by "cousin Blob", Trichoplax, as the basal lineage to this group. This scenario proposes that these two very different bauplans of animals evolved in parallel, not in the ladder-like progression favored by many other studies.
Looks like it's time to re-write some textbooks.
Wednesday, January 28, 2009
Tuesday, January 27, 2009
Money, dough, bullion, $$$, Benjis, and jobs for graduates! Woo-hoo! Did you get half Very-Goods, half Excellents, but were left out to dry for FY2008 at NSF or NIH? Are you about to graduate, and the post-doc offers and job postings you expected never materialized? I don't want to jinx anything, but it looks like it paid off to fawn over Obama after all.
FY2009 should already be way better with the NIH receiving nearly $4 billion and NSF $3 billion if the stimulus package passes. There is also a chance that the new Prez, by all indications a friend of science [1,2,3,4], will seek steady increases. If you haven't already seen it, this letter written to Obama by 49 Nobel laureates argues for something along those lines, as well.
Maybe I'm an eternal optimist, but this looks pretty good, guys. I just hope it doesn't turn into $50 million grants for tired work and Eppendorf bling-bling in a handful of labs. (I hope it's declared unpatriotic to buy pre-cast gels.)
Thursday, January 8, 2009
R! For those of you who haven't seen, here's the latest nod to the popularity of R--by the New York Times. My favorite part of the article is the Cheney-style defense of SAS, relying on shoddy logic and shameless scare tactics (so 2008!). Also noted: while coding mistakes by evolutionary biologists are unlikely to kill anyone, loss of any customers does siphon off cash from the SAS Institute.
Yes, it's been quiet around here, mainly because everyone is shooting for the January 9th NSF deadline.
Thursday, January 1, 2009
I'm so glad to start 2009. After leaving my friends' party tonight, I actually managed to snag a cab in New York City. For the 45 or so blocks, the Pakistani driver and I yacked on and on about life, love, marriage- but mostly about our goals and aspirations for the new year. When we finally reached my building and had to part ways, we said to each other, in a manner of speaking, "This was nice - I hope I get to see you again someday..." and as I paid him, he passed along his medallion number - 2N46. Could he possibly realize the significance, i.e., 2N=46- the number of human chromsomes - what a unique medallion he has?? I just know that I won't forget it- and, in this important year of Darwin's 200th birthday, what a nice way to start the year... Happy New Year everyone. May we all resolve to find our commonalities and move beyond our differences, and make this a special and important new year,
Posted by Susan Perkins at 3:04 AM