Re: Re: News Flash: Ungulates and Dinosaurs Together 80 million Years Ago (fwd)

[Thomas_R_HOLTZ@umail.umd.edu (th81)]

Betty Cunningham writes:

>According to an AP news wire (courtesy of Darren Naish):

>> > In his study, Archibald said that rat-sized tooth fossils recovered
>> > from the Bissekty Formation in Uzbekistan resemble the shape and
>> > characteristics of teeth found in animals that lived millions of
>> > years later. The teeth had the flat, squared grinding surfaces
>> > similar to what is found now in the teeth of herbivores. Archibald
>> > said that fossils from 65 million years ago show that the diversity
>> > of ungulates then alive led to eventual development of animals as
>> > varied as antelopes, whales and elephants.
>
>   ok, but-um- I seem to remember a NOVA special on genetics that
>discussed how the cow's stomach (what makes a cow an ungulate) was

No, Ungulata is the clade of hoofed mammals.  I think you are thinking about
"ruminant".

>developed to process grasses into more easily digestable stuff for the
>animal's system to cope with, ONLY GRASSES WEREN"T AROUND AT THE TIME
>if these are 'ungulate' teeth, right?
>   So, what were these animals eating that would account for grazer's
>teeth?  Wouldn't that sort of teeth seem to indicate (by the meager
>understanding of ungulates that I have) that these animals chewed a
>cud?  Isn't that a rather advanced characteristic?

I think what Archibald was saying is that the Uzbekistani teeth show
synapomorphies of Ungulata.  Most mammalian lineages have unique dental
characteristics, making them easy to identify from a tooth or two.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661

"There are some who call me...  Tim."