[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Rép : Post–K-Pg Radiation of Placentals -- open access!!!



I'm planning to write a review of this paper once I've finished reading the so-called supplementary information. However, as has been mentioned, it's a book of 131 pages, so I haven't had time to read more than half of it yet!

But the really important thing is that the "paper" behind the paywall is, in reality, just an extended abstract. It presents the showiest results and has all the pretty pictures, but that's it. The _entire_ "materials and methods" section is in the allegedly supplementary information.

In a comical turn, this "supplementary" information has _its own_ supplementary information ("appendices S1 to S4"), which isn't even hosted on sciencemag.org, but on morphobank.org!

Do you realize what all this means, dear colleagues, laddies and gentlewomen?

It means THIS IS AN OPEN-ACCESS PAPER!
Here you go: http://www.sciencemag.org/content/suppl/2013/02/07/339.6120.662.DC1
Then cackle madly and click on "download supplement"!

(As an aside, if the very Late  Cretaceous mammal _Protungulatum
> coombsi_ belongs in the genus _Protungulatum_, then based on the
> published phylogeny, this pushes back the origin of crown placentals
> into the Mesozoic. But the Supplementary Material is skeptical
> regarding _coombsi_ being bona fide _Protungulatum_.)

In particular, *P. coombsi* is known only from "the tooth, the whole tooth, and nothing but the tooth", so its affinities are difficult to evaluate.

_Protungulatum donnae_ is not  actually "new"; it was named in 1965.

As its name indicates, it was immediately thought to be "the first ungulate". It was also thought to be Cretaceous in age for a long time.

At last year's SVP meeting, during a discussion of the age of *Purgatorius*, Bill Clemens recited "the four horsemen of the apocalypse": "*Protungulatum*, *Oxyprimus*, *Mimatuta*, *Baioconodon*!" They show up immediately after the boundary in western North America and must have immigrated from elsewhere, in keeping with the statement by O'Leary et al. that the repopulation of North America must have been accomplished by "immigration from refugia".

Tarsal bones referred to this  critter indicate it was terrestrial
> (in keeping with euungulate affinities).

Warning: mammalologists are usually happy to refer isolated tarsals to taxa otherwise known only from isolated teeth if they have the expected size. The relationship between tooth size and the sizes of various tarsal bones is apparently well known and fairly constant, so this is less scary than it sounds like; but there are bound to be occasions where this practice puts the LOL in mammalology.

The superficially shrew-like  "placental ancestor" depicted in the
> article was inferred by the Science study to be scansorial (probably
> primitive for crown therians, i.e. placentals + marsupials). It's
> interesting to contemplate that therians became scansorial and
> arboreal at about the same time (or likely before) theropods are
> inferred to have headed into the trees. Coincidence?

The dryolestidan *Henkelotherium* was also arboreal or scansorial. But I don't think dryolestidans are known from before the Middle, perhaps even Late, Jurassic.