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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.
I have now downloaded the first part of the supplementary information. Table 3 of http://www.nature.com/nature/journal/v446/n7135/extref/nature05634-s1.pdf lists the calibration points. It contains (at least) the following mistakes:

- *Monotrematum* is probably not a crown-group monotreme. Thus, Monotremata may be younger than 63.6 Ma.
- *Tribosphenomys* is far from being a crown-group rodent! Rodentia (unlike Rodentiamorpha) is younger than 57.25 Ma (...and I wonder where they got such a precise date...). Note that the reference Bininda-Emonds et al. cite makes this quite clear (it coins the name Rodentiamorpha).
- Not that I knew anything, but I'd be quite surprised if *Eodendrogale* were a crown-group scandentian. Thus, the crown-group of Scandentia may well be younger than 44.5 Ma.
- Same for *Dendrotherium* being a crown-group dermopteran.
- The genus *Tarsius* is 44.5 Ma old? Difficult to believe. I'd say a name change is in order.
- *Diacodexis* is a paraphyletic series of species around the base of Cetartiodactyla (which means that at least some of those species should get new genus names). Putting "*Diacodexis* sp." into Suiformes does therefore not look defensible to me, but I'll try to find the reference.
- Obviously, *Pakicetus* is not a crown-group whale. The crown-group of Cetacea (Autoceta) is much younger.
- *Eomanis* is far from a crown-group pangolin...
- I'd be very surprised if *Ageinia* turned out to be a crown-group bat. Thus, chances are high that the crown-group of Chiroptera is younger than 52.2 Ma.
- I'd be surprised if *Riostegotherium* turned out to be a crown-group dasypodid. But that's outside my area of knowledge.
- The crown-group of Tubulidentata consists only of *Orycteropus*. Obviously *Myorycteropus* can't be part of that...
- *Nortedelphys* was indeed described as a didelphimorphian, but I don't buy it. It's "the tooth, the whole tooth, and nothing but the tooth" (as usual in the Mesozoic). In any case, considering it a _crown_ didelphimorphian really stretches it.
- Paucituberculata... all extant paucituberculates are caenolestids, and the fossil is most likely not one of those...
- I bet the fossil notoryctid is outside the crown-group.


Much sloppier work than I imagined.