Re: Cretaceous rodent and earliest NA bird tracks

[K and T Dykes <ktdykes@arcor.de>]

<<World's oldest Rodent fossil found in Thar desert:
http://sify.com/news/fullstory.php?id=14019125>>

I've been looking at this intriguing report, Ben, and I can't help thinking
the author has got some significant details tangled.  Their are several very
odd claims and the language is a bit wobbly.  It states researchers dug
'millions of tonnes of sand' in early 2005.  If so, then their stamina is
startling.  Even a gang of fully spinnached Popeyes couldn't match that
level of industry.  He makes several references to 'PM Dutta'.  I wonder
what PM Datta actually said.

The upper tooth is referred to in the report as a 'molariform', and rodents
do have such teeth.  However, they're much more often technically termed
molars.  'Molariform' includes both molars and the ancestral version which
may, (in some cases), have been subject to replacement.  Narrowly defined
molars aren't replaced.  It also reports the presence of five roots, and
that sounds very un-rodenty, not to mention interestingly strange.  Assuming
the author got the rough age right, (between 142 and 93.2mya is what they
wrote), then this location is presumably Lower Cretaceous.  Coming up with
any relevant Gondwanan mammalian upper teeth for comparisons is going to be
tricky due to the chronic shortage.  That's another detail which makes this
intriguing.
Cheers
Trevor

Mesozoic Eucynodonts, an internet directory
http://home.arcor.de/ktdykes/meseucaz.htm
The Mesozoic - more than just the dinosaur.