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



Several popular accounts discussing therapsids mention the presence of
'whisker pits' - little foramina on the snout bones that prove the
presence of vibrissae.  They have been reported in _Cynognathus_ and
_Prebolosodon_ for sure, and some workers have gone as far as citing
them as evidence for a furry pelt in these animals. This in itself
seems reasonable _if_ it can be shown that 'whisker pits' are really
proof of whiskers: and I recall reading that such a correlation could
not be made in the anatomy of certain seals. If anyone knows any more
on this, or could help with information on the presence or absence of
whisker pits and/or vibrissae in any tetrapod, please do tell. Many


Most of us interested in dinosaurs have a vested interest in other
areas of vert palaeo, so I don't think I deserve scolding if I mention
the recently published work of Thewissan et al. concerning the
evolution of osmoregulation in the earliest whales (recent
_Nature_). Thewissan et al. have shown that the salinity of water
imbibed (during tooth formation) can be revealed by analyzing oxygen
isotopes. They found that _Pakicetus_ and the new (in press) genus
_Nalacetus_ were still drinking fresh water - I think that
_Ambulocetus_, though found in marginal marine strata, was still
coming inshore to drink freshwater - and it wasn't till _Indocetus_, a
form about 4 Ma later than _Pakicetus_, that drinking sea water became
regular for whales. I don't recall if _Rodhocetus_ was mentioned -
this taxon is important in that it was found in pelagic sediments well
off the continental shelf.

That's enough jabber from me.

"Uck - human females are so repulsive"
"Women - can't live with 'em.. can't kill 'em"