Re: Long Bone Scaling in Neosauropod Dinosaurs

[Glen Ledingham <glenled@yahoo.com>]

I agree: camels are off-topic, except as they apply to
dinosaurs.  However, since you have questions:

Dromedaries are "stiltier" than the others.  The real
exception, which I should have remembered, is
Alticamelus from Rancho La Brea.  On the other hand,
A. might have wandered in from the very hot desert.

Compared with a modern rhino or hippo, an elephant's
legs are long.  I probably should have included
baluchitheres, which had long but heavy legs.  

One could say that human legs are stilt-like, compared
to bonobos and australopithecines.

Lastly, for some very "stilty" dinosaurs, look at
ratites, which live in open ground, and herons which
wade.

My point was that long legs are adaptations
to/advantageous in different habitats, and I suspect
that this applies to neosauropods.

Glen Ledingham  

   
--- "T. Michael Keesey" <keesey@gmail.com> wrote:

> On 8/29/07, Glen Ledingham <glenled@yahoo.com>
> wrote:
> > Long-legged mammals seem to have evolved their
> stilts
> > for a number of reasons:  elephants and giraffes
> for
> > reaching goodies, moose for walking through bush
> and
> > bog, camels to lift their bodies away from hot
> ground.
> 
> Maybe this is a bit off-topic, but ... most living
> camelids don't live
> in hot desert areas. Of the six living species, four
> live at high
> altitudes (Lama glama, L. guanicoe, Vicugna vicugna,
> V. pacos), one
> lives in a variety of dry climates both cold and hot
> (Camelus
> bactrianus), and only one lives exclusively in hot
> desert areas (C.
> dromedarius). All of them have stilt-like legs, so
> isn't it more
> likely that C. dromedarius' usage is an exaptation?
> Or is hot desert
> the ancestral habitat, with the montane species
> being derived? (I
> don't know a lot about camelid evolution.)
> 
> >  Perhaps the neosauropods did the same.
> 
> I have to say that the legs of elephants and
> neosauropods don't look
> all that much like "stilts" to me (with the possible
> exception of
> brachiosaurid forelimbs, although even those are
> more like columns
> than stilts). What is the definition of "stilt-like"
> here? (Apologies
> if this was mentioned and I missed it.) Are human
> legs "stilt-like"?
> 
> -- 
> Mike Keesey
>