Re: Complaining

[GSP1954@aol.com]

A number of galloping mammals, large ungulates included, have stronger 
(more robust boned) arms than legs, probably to help carry the big heads and 
necks sometimes with horns and antlers. A lot of galloping mammals have weaker 
arms than the legs - small ungulates, cats, rabbits, and so forth (not sure 
about canids, they look fairly equal fore and aft). But rabbits are small 
things with hyperflexible backs, and with fairly strong arms they can gallop 
on. Hadrosaur arms were very slender relative to mass and I doubt even juvies 
could gallop on them, much less the grownups. Add to that their rigid 
dorsal columns and lack of a galloping heritage in the more strongly bipedal 
small ornithopods, and galloping hadrosaurs are biomechanical madness. 

GSPaul


In a message dated 4/30/13 12:06:03 PM, biologyinmotion@gmail.com writes:

<< Good point - though the arms don't necessarily need to be as strong as 
the legs; they merely need to be capable of bearing full load during the 
absorption phase of the gallop.  For most galloping animals (especially large 
ones), this necessitates that the forelimbs have a similar load bearing 
capability to the hind limbs.  However, it is possible for the hind limbs to be 
especially robust as primary propulsion structures and the forelimbs to be 
rather weaker but still capable of bearing the prerequisite loads.  Lagomorphs 
are probably the most obvious example.


None of that, of course, suggests that hadrosaurs would gallop 
quadrupedally.   >>

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