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

Mononykus again

Apparently the fossorial interpretation of the functional anatomy of Mononykus 
derives solely from the fact (if it is one) that the only parallels to this 
anatomy (apart from birds) are found in digging animals (cp. Judy Molnar).  
However, comparative studies are merely useful, not definitive.  The neck is 
particularly troublesome in the fossorial interpretation (cp. Holtz), but the 
claws taking over the manus completely, and yet lacking any shovel-like shape, 
make them radically unsuited to digging in earth.  But are they unsuited to 
"digging" in bark?  Bark stripping is, after all, a kind of digging, but one in 
which shovel-like manus are probably a hindrance.  Furthermore, is it not true 
that the dentition of root and bulb eaters is at least to some extent what we 
might call "molarized"?  This does not fit the dentition known for Mononykus 
(cp. Holtz).  

Matt Wedel writes, "... don't modern animals that search for bugs under bark 
tend to have really, really long appendages?  ...  What really puzzles me isn't 
why the claw is so big, it's why the arm is so short."  In birds, the longer the
wings the less the proportional downward ("inward") force that can be applied to
flapping its wings.  Eagles and condors soar a great deal -- the real champions 
of flight, song birds and hummingbirds, have very small wings.  If a great deal 
of penetrating force is needed for the sharp Mononykus claws to insert below the
targeted strip of bark, then the same muscles used by birds in down-flapping 
come into vigorous play.  Furthermore, a backward jerking motion of the body 
might also utilizing these muscles to some degree as well, and short, muscular 
arms would also be an advantage in such a technique.  There is nothing in the 
design of the claws to suggest that they could not also be used in the fashion 
attributed to the Aye-Aye (cp. Molnar); and it would be wrong almost a priori to
suggest that such claws would not be multifunctional.  (Although they would be 
inefficient in egg stealing [cp. Martin Human]; and the habitat is wrong [cp. 
Holtz] for prying open mollusks [cp. Schneiderman], not to mention -- forgive 
the pun -- the manipulation problem).  The disappearance of hands in favor of 
manus made entirely of claws could be understood both as the result of the added
utility of such claws, and the deleterious effects of infection from bark 
splinters embedded in the soft tissues of the manus.