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Re: Giraffatitin brancai Vs Brachiosaurus brancai Vs Brachiosaurus altithorax



>>The only paper I know of describing this skull is apparently Carpenter
and Tidwell, 1998, in Modern Geology, Vol. 23, pp. 69-84.<< --- Ken Kinman

Yup.... I was searching the archives of the list this morning and found the post from Tidwell.

And while I'm still in a Brachio sort of mood...... I was thinking about the restoration change from the mildly sloping swan-like neck to the "lets stick it straight out at an angle like a warped 2x4".... Is this just playing on the percentage of ossification of the elongated cervical ribs dictating how flexible the neck actually was.... or... is there something else going on here that I don't know about? I know that with a back angled up between 25-35 degrees, in order to get the neck to look like a more vertical S, it would require some hefty flexibility at the base of the neck, not to mention the bottom third of the necks vertebral column would really have to be straining. If memory serves, Kent Stevens figured out a slope in the neck between 10 and 15 degrees per vertebra? And I was looking at the cervical vertebrae........ The first 6 have low, rounded neural spines... but when you get to 7 there is this huge triangular-looking spine that looks nothing like the others! ! before it. This I'm guessing is where the big dorsal neck elevating muscles were anchored... longer lever arms....simple mechanics....

With this tall neural spine, and the longer vertebrae at the base of the neck, is this more of the real reason why recent reconstructions have the neck in a straighter orientation, with a slight slope and with a thicker dorsal side made up of bulging muscle close to its base? Did the neck form more of a gentle curving over after the 7th cervical with it's hugh neural spine?

Kris