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HYRACOIDEA, how do I love thee



Spot the difference between the list's moderated and unmoderated versions. Kelly
Milner-Halls would never previously have gotten away with disgusting sexual
innuendo;-)

As for the hyraxes, yes, some mammalogists (notably Prothero, Manning et al.)
now insist that they should be included amongst the perissodactyls
(perissodactyls are horses, tapirs, rhinos and their extinct relatives). They
point to marked similarities between the two groups: hey, when Owen created the
name _Hyracotherium_ he actually had perissodactyl-hyracoid similarities in
mind! If this relationship is correct, hyracoid-tethytherian affinities are
scuppered (tethytheres are proboscideans, sirenians and desmostylians) and the
appealing notion of a hyrax as a 'hamster-sized elephant' must be tossed aside.

_Hyracotherium sandrae_, a teeny tiny little horse that weighed 3-5 kg, is the
closest either perissodactyls or tethytheres got to 'hamster-sized'.

It's worth pointing out that, while proboscideans are closely related to two
amphibious/aquatic groups (the sirenians and desmostylians), it is not correct
to state that elephants are descended from aquatic ancestors. I say this because
those who advocate the 'aquatic ape' theory often use elephants as models of
descent-from-aquatic-ancestors (elephants and humans share a few irrelevant
characters, in particular breast and genital morphology). Early proboscideans
like the moeritheres may perhaps have been amphibious (they have been
reconstructed like that, but I'm not convinced, and there have even been
suggestions that _Moeritherium_ is actually a basal sirenian) but they are
divergent. Late Palaeocene proboscideans like _Numidotherium_ don't appear much
to do with an amphibious or aquatic lifestyle. Further, it's increasingly
recognised that the shovel-tusked mastodonts like _Platybelodon_ were not marsh-
dwelling water-weed eaters, but in fact stripped trees off bark and lived their
lives on dry savannahs!

Of course, if you follow French ichthyologist Francois de Sarre and his Initial
Bipedalism theory - kind of 'Humans Came First' - all mammals are direct
descendants of marine tetrapods. And bipedal ones that used their brains as
floats at that. Of course.

Dong initially suggested that _Dilophosaurus sinensis_ had a beak for tearing
open dinosaur bellies. Presumably this was prior to lab preparation. If not, did
he have any justification for the idea? The skull (figured in _Vertebrata
PalAsiatica_) is chunky macropredatory theropod and looks wholly unsuited for
a beak, but nevertheless the idea is interesting as certain artistic characters
(it all began in 1978 with a little sketch in a _Science_ article...) have been
restoring their coelophysoids (sensu Holtz 1994) with beaks. Yes, I'm writing
this so I can justify the forwarding of this post to a list called 'dinosaur
list'.

"It's over sir, the rebels are fleeing into the woods"

"I thought I told you to run away"
"Come on John, give me some credit"

"I don't know which species is worse..."

DARREN NAISH