Sauropod necks and rearing

[GSP1954@aol.com]

Again a long discussion on a subject without proper reading of the 
literature. Specifically my 1998 paper Terramegathermy and Copes Rule in the 
Land of Titans, Modern Geology 23:179-217. In it I point out the following. 

For a century people have been prattling on about how sauropods saved oh so 
much energy by standing still and using their long necks to sweep for 
vegetation. And no one has ever done the calculations to show this is true. 
The "science" of paleontology marchs on. Very long necks are rarely evolved 
because they are costly in terms of growth and maintainence, as well as the 
extra respiratory work needed to breath through elongated trachea. At the 
same time the energy saved by using a long neck to reach a short plant that 
can be reached simply by walking up to the plant like any sensible low 
feeding herbivore is trivial. A mere few ounces worth of food. Until someone 
bothers to do some actual science and publish estimates showing that 
sauropods really did save significant energy by using long necks to reach low 
plants rather than just taking a few more steps it is not science. 

As for rearing sauropods I plotted data showing that most sauropods had 
posterior dorsals stressed for bipedalism in the same manner as kangaroos and 
giant slothes, and much stronger than mammals that rear only occasionally in 
the wild such as horses and elephants (published photos show them rearing to 
feed). There is a long line of excellent studies demonstrating the 
specialized rearing adaptations seen in many sauropods for rearing dating 
back to old Riggs about 100 years ago. There has never been a study providing 
conclusive evidence that any sauropod could not rear. That this subject 
remains controversial is more a sign of failure to appreciate the anatomical 
evidence driven by inherently speculative opinions that animals so big could 
not stand on two legs, or blood pressure problems were too severe, than the 
existence of a real problem. 

Concerning giraffes, there is abundant evidence that they regularly high 
browse, especially bulls, often to the extent of increasing risk of predation 
by stretching the head and neck to the vertical maximum (check your Dagg & 
Foster 1974, and J Du Toit 1990 Afr. J. Ecol. 28:55-61). 

As for sauropod neck posture that's been messed up badly by some recent work, 
but currently the only sauropods shown to have horizontal necks, diplodocids, 
have strong rearing adaptations, and in all other sauropods there is good 
anatomical evidence that the neck could be elevated at least 45 degrees, and 
perhaps subvertically. 

Greg Paul