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

Re: Giant flightless birds



"Thomas R. Holtz, Jr." wrote:
> At 10:05 AM 5/11/99 -0400, Larry Febo wrote:
> >OK,...here`s something else.There seems to be a trend in the number of
> >digits possessed by theropods. That trend seems to be a loss of such digits.
> >A good reason for lose of digits might be that they simply were not needed
> >as birds evolved more sophisticated wing structures.

The only 'bird-relatives' I can think of that lost digits are 'terror
birds' and Mononykus, both of whom seem to be more efficient at stabbing
things with their claw-stub then with multiple claws.  Are there others?

Birds also have the odd trend of loosing toes...as with the two-toed
ostrich.  Maybe birds as a group have a genetic preponderance to loose
extremities?

> >Again, it seems to make more
> >sense that a terrestrial animal would always be in need of good grasping
> >ability of its forelimbs for ther procurement of prey.
> 
> Tell that to a dog, a hyena, or other jaw-based hunter!!  These animals do
> not use the forelimb to aquire prey: at best they use them to stabilize the
> victim while the jaws do their work.  Interestingly, these predators also
> have very powerful jaws and neck muscles, claws which are not well curved
> (compared to cats), and very long and slender legs: these same features are
> also seen in tyrannosaurids.

My dog uses her front paws to hold bones while she attempts to break
them open to get to the good stuff.  She also eats corn on the cob by
holding the cob.  The grasping ability is still there though it may not
be used to bring DOWN prey as oftin as felines use them.  

As a further note canids dig much more often then felines do.  Perhaps T
rex dug it's nest/den with it's forelimbs.  

-Betty

-- 
Flying Goat Graphics
http://www.flyinggoat.com
(Society of Vertebrate Paleontology member)
-------------------------------------------<,D,><