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

Re: *Fruitafossor*

True. Interestingly, in a study that appeared recently in Nature, Zack et
al. (2005) found that _Plesiorycteropus_ and _Orycteropus_ were sister taxa.

Though... that wasn't exactly the focus of their study.

Molecular phylogenies are also pretty consistent in finding a clade that
includes ruminants, whales and hippos to the exclusion of other
(cet)artiodactyls. Yet this ruminant+"whippomorph" clade is not supported
by the paleontological/morphological evidence. Even Boisserie et al. (2005)
reject a unique relationship between ruminants, hippos and whales; instead
they find an (anthracothere+hippo)+whale clade that is closer to pigs than
to ruminants.

The bootstrap support for all this is less than 50 %. Ruminants come out in an unresolved trichotomy with (pigs + (anthracotheres + whales)) and *Diacodexis pakistanensis* (so it's no longer the position of the whales that's problematic, it's the position of the ruminants! The irony!), and camels* are absent... not to mention truckloads of Eocene and later artiodactyls that are funky to various degrees...

* The sistergroup of Ruminantia in morphology; the sistergroup to all the rest of Cetartiodactyla in all molecular analyses.

There is hope. The Afrotheria clade, which is canonical in molecular
phylogenies, has come under attack from morphological studies - but it
appears to be accruing support from the fossil record. For example, Zack et
al. (2005) recently found a link between macroscelideans (elephant shrews)
and a group of North American 'condylarths' called apheliscines

Plus, they find one potential synapomorphy for (the above clade + Paenungulata + Tubulidentata)! :^)