Re: Sauropod Necks As Weapons

["Williams, Tim" <TiJaWi@agron.iastate.edu>]

Dann Pigdon wrote:

> Somewhere along the way sauropods may have become too large to regularly
> adopt a bipedal, or even tripedal, posture, but some (such as
> diplodocids) may have retained features from their (smaller) ancestors
> that did (such as larger hindlimbs than forelimbs).

This raises an interesting point: are the relative lengths of the fore- and
hindlimbs of diplodocids a primitive sauropodomorph character, or a reversal
to the primitive sauropodomorph condition?  I think the evidence supports
the latter: Basal sauropods have limb proportions consistent with obligate
quadrupedalism, so any facultative bipedalism (or "tripodal-ism") adopted by
diplodocids is likely a secondary specialization.

There is a possibility that the short forelimbs of diplodocids were evolved
to put the head and neck closer to the ground, not for bipedal/tripodal
rearing.  Though the two are not mutually exclusive.

And to respond to the original question in this thread: I think it
implausible that the neck would be used as a weapon when the tail could have
served at least as effectively to "swat" an approaching theropod.  Some
sauropods may even have had tails specialized for this purpose ("whiplash"
tails; tail-clubs.)



Tim