Bipedalism
Bipedalism is shown
through several different post-cranial elements (including the pelvis, lumbar
vertebrae, femur, fingers, and toes). Interestingly, bipedalism can also be
determined through the cranium. Specifically, in the cranium, the foramen
magnum can be evidence of a hominin/individual being bipedal or not. If the
foramen magnum is shifted forward, then it can be evidence of bipedalism. Scientists
believe this forward shift is an adaption to for the skull to be able to
maintain its’ “ balance
of the head atop the cervical vertebral column,” (Russo & Kirk, 2013).
Daubenton was the first to recognize this forward shift in 1764, which was later
confirmed by Broca (1872) and Topinard (1890). Although there is heavy controversy towards
using the shifted forward foramen magnum since the discussion of its presence in
the Taung child. One reason people are hesitant to use this method due to the
inconsistencies present within the position of the foramen magnum in primates alone.
However, based on the numerous studies conducted on the position of the
foramen magnum in different hominins, bipedal mammals, and humans it’s undeniable
to acknowledge a pattern. These studies found that humans, bipedal rodents, bipedal
marsupials, and various other bipedal mammals have a pattern of anterior facing
of the foramen magnum. This method/pattern of determining bipedalism in species
is a newer concept but be used in future cases to understand the evolutionary
map and the human fossil record.
Citation:
“Human Skull Evolved Along with Two-Legged
Walking, Study Confirms.” UT News, 9 Nov. 2018, news.utexas.edu/2017/03/17/human-skull-evolved-along-with-two-legged-walking-study/#:~:text=Researchers
confirm that the evolution,key feature of the skull.&text=Compared with
other primates, the,foramen magnum, is shifted forward.
Russo, Gabrielle A., and E.Christopher Kirk. “Foramen Magnum Position in Bipedal Mammals.” Journal of Human Evolution, vol. 65, no. 5, Nov. 2013, pp. 656–670. EBSCOhost, doi:10.1016/j.jhevol.2013.07.007.
great job here! and nice research with the Russo and Kirk paper. I really like that one. I like how you note that it isn't a perfect inicator and that there is debate here. I honestly wonder if we need to rethink our stance(!) on the relevance of bipedalism in early hominins. Are we concentrating too much on this and not on other aspects? I don't know but i think that in the next 10 yrs there may be a shift away from bipedalism as the earliest thing we expect to see in hominins.....
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