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Re: ... vs energy deficient gigantothermy (boo hiss)



----- Original Message -----
From: "Tim Williams" <twilliams_alpha@hotmail.com>
To: <david.marjanovic@gmx.at>; <dinosaur@usc.edu>
Sent: Monday, May 07, 2001 10:44 PM
Subject: Re: ... vs energy deficient gigantothermy (boo hiss)


> >- I've forgotten whether *Steropodon* or *Kollikodon* is estimated at 1 m
> >(the respective other was more normal platypus size, AFAIK), but have any
> >others turned up from Cretaceous Australia?
> >- Has the 1-m-estimate turned out to be wrong anyway?
>
> I think 1m long is excessive for _Steropodon_ - unless it had a very long
> tail.   I've seen an estimated head-to-tail length of 35cm quoted for this
> animal, which puts it close to the modern platypus.  This appears to be at
> the lower end of estimated body lengths.

Ah! Thanks! (Did I confuse it with *Kollikodon*?)

> _Steropodon_ and _Kollikodon_ may not be the only Cretaceous monotremes
> named from Australia.  Originally thought to be a pantothere,
_Teinolophos_
> may be a third genus of monotreme from EK southern Australia.
> _Teinolophos_'s jaws and teeth are much *smaller* than those of the other
> two.
>
> _Ausktribosphenos_ (which is known from at least seven jawbones, last
count)
> is probably a eutherian - perhaps an early erinaceimorph
("proto-hedgehog").

*Ausktribosphenos* is certainly an australosphenidan, like monotremes,
*Ambondro mahabo*, possibly gondwanatheres and probably *Teinolophos*. These
evolved tribosphenic teeth independently of boreosphenidans (placentals,
marsupials, and similar mammals). Have a look or two at

Luo Zhexi ["Zhe-Xi Luo"], Richard L. Cifelli & Zofia Kielan-Jaworowska: Dual
origin of tribosphenic mammals, Nature 409, 53 -- 57 (4 January 2001)