> Are elephants really near the physical limits? Remember that the
> limits of size of an animal also depends a lot on its geometry; a
> two-legged creature cannot get as big as a four-legged one, and the
> way the bones connect play a great role in the strength of the
> structure.
>
> (BTW, it is hard to call dinosaurs a hypothesis, since we do indeed
> have their sizeable bones)
AN elephant's bones are near the tolerance limits for those bone designs using
those bone materials. A Giraffe exerts much more stress on its neck bones than
an elephant does on any of its own. That a giraffe's neck is engineered like a
cantilevered truss is much more of a natural engineering feat than the shock
absorbing capabilities of the elephant. The reason why dinosaurs that we know
popularly (most were actually quite small) are so big is that they developed at
a time when all or most of the continents were part of the Pangea super
continent. Studies have shown that there is a direct correlation between the
evolved sizes of animals and the size of the land mass which they inhabit. For
example the wooly mammoth, of which frozen remnants have been found in the
tundra of Siberia, which was larger than the elephant, and carried much more
mass in its tusks than current elephants, as it was slowly killed off by post
ice age man, the last refuges in which its fossils were found to have lived most
recently ( from what I've heard as recently as 4000 BC) were small islands in
the arctic ocean north of Finland. As their food supply was restricted by the
size of their domain as it was cut off from the mainland by rising seas, they
slowly evolved into a 'mammoth' of only 3 or 4 feet in height.
-- TANSTAAFL!!! Michael Lorrey ------------------------------------------------------------ mailto:retroman@together.net Inventor of the Lorrey Drive MikeySoft: Graphic Design/Animation/Publishing/Engineering ------------------------------------------------------------ How many fnords did you see before breakfast today?