Tuesday, August 19, 2008

Hot Off the Press: Evolution 62(8)

Although the article layout still looks like a 13-year-old kid spilled a bag of bad ideas onto a page, a new issue of Evolution arrived in the mail. (Take a look at that crisp and readable 1980s article design.) At least the contents seem unaffected by style.

Liu et al. augment the approach initially outlined most recently in Edwards et al. (2007) and Liu and Pearl (2007; see previous post), and hinted elsewhere, for estimating species trees with multiple-allele sequence data. Brandley et al. argue that reconstructions of ancestral states alone can reveal important insights into the evolutionary history of morphological changes--their number and directionality, for example. Although, they employ a nifty model, it is likely that ignoring some well known violations of the models of character evolution yield spurious results (in this and hundreds of other studies). In other words, I don't buy the regain of limbs in squamates. Still, the regression analyses of traits associated with lizard- or snake-like body form make for nice lecture material. I wonder if they could post the data and code for R instruction? (they did!Hansen et al. expand the earlier models of quantitative character evolution by giving consideration to the shifts in trait optima, in addition to character state shifts themselves. Strasburg and Rieseberg, and Currat et al. examine the magnitude of introgression in an empirical multi-gene study of sunflowers and in simulations of invading/local populations, respectively. Finally, Rabosky and Lovette develop a method for estimating speciation and extinction rates that vary continuously through time, and find that the common slow-down in species accumulations are driven by lower speciation, not higher extinction rates.

2 comments:

Matt Brandley said...

Thanks for the reminder.

Anyone can download the limb reduction data here:

http://socrates.berkeley.edu/~brandley/datasets/datasets.htm

I may put the figures on my website too since they look like garbage in print.

Anonymous said...

Thanks, Matt!