Re: *Fruitafossor*

[Tim Williams <twilliams_alpha@hotmail.com>]

Christopher Taylor wrote:

>     MacPhee's separation of _Plesiorycteropus_ was due to a lack of
> phylogenetic support for connecting _Plesiorycteropus_ to _Orycteropus_, as
> opposed to e.g. any other ungulate or myrmecophage. However, nor did he 
> find
> any direct evidence that _Plesiorycteropus_ was _not_ related to
> _Orycteropus_.

True.  Interestingly, in a study that appeared recently in Nature, Zack et 
al. (2005) found that _Plesiorycteropus_ and _Orycteropus_ were sister taxa. 
 I'd bet dollars to donuts that the two are closely related.


Nick Pharris wrote:

> Well, molecular phylogenies are pretty consistent in placing Pholidota near
> Carnivora and Xenarthra a long way away from either of those.

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 point of this rambling is that I'm skeptical of this molecular-based 
Pholidota+Carnivora clade.  True, it comes up in almost every 
molecular-based tree; and it does have some morphological support.  However, 
these same molecular analyses typically find very weak support for the 
Pholidota+Carnivora clade (e.g., Murphy et al., 2001).  I'd like to see more 
fossil data.

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 
('Hyopsodontidae').



Tim