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Re: Dinos' loss was not mammals' gain

Olaf R. P. Bininda-Emonds, Marcel Cardillo, Kate E. Jones, Ross D. E. MacPhee, Robin M. D. Beck, Richard Grenyer, Samantha A. Price, Rutger A. Vos, John L. Gittleman & Andy Purvis: The delayed rise of present-day mammals, Nature 446, 507 -- 512 (29 March 2007)

So... they constructed a gihugrongous supertree, and fed it into a molecular dating program after aligning 66 genes for as many species on the tree as possible. I don't see why we shouldn't just regard the results as yet another set of molecular divergence date estimates. 30 calibration points were used. I'll try to get the supplementary information tomorrow to check what they are.

The calibration points were used as minimal ages only*. Had they used maximal ages, too, I bet the results would have been different.

* One exception: the Bathonian age of *Ambondro mahabo*, narrowed down by fiat to 166.2 Ma, was used as the precise age of the mammalian crown-group. Having a fixed age for the root makes molecular dating easier, but I can't see how that justifies putting so much confidence in the Middle Jurassic terrestrial fossil record...

There are only three outgroups in the tree: *Gallus gallus*, *Xenopus laevis* and *Xenopus tropicalis* (...isn't that *Silurana tropicalis*?). This increases the risk for their branch lengths having unwanted effects on the branch lengths in the ingroup.

Just over 3 months from reception to acceptance, and just under 2 from acceptance to publication. Fast.