A new study goes to confirm a previously debated theory. Research shows that bipedalism or walking on two legs led to an evolution of the skull. This was shown thanks to one of its most specific elements, the foramen magnum, a large hole.

Research on the matter was carried out by University of Texas at Austin scientists. They released their study results earlier this week. This was published in the Journal of Human Evolution. Gabrielle Russo, formerly of the University of Austin, now of Stony Brook University was part of the research.

The Connection Between The Skull And Bipedalism

A much-debated theory revolves around the foramen magnum. This is the large hole at the base of the human skull. The spinal cord is known to pass through it. Some scientists claim that this element evolved thanks to or alongside bipedalism. Or more exactly, it may have helped humans balance their heads “directly atop the spine”. However, other researchers contest this theory.

The current study went to offer further proof to support the idea. Some of the controversies revolve around the fact that the foramen magnum was believed to be shifted forward solely in humans. But according to this new study, this may not necessarily be so.

The team studied the forwards-shifted foramen magnum of humans. At the same time, they studied this same element in their bipedal fossil relatives. Also, they studied the skull and its foramen magnum in 77 other mammal species. These included primates, marsupials, and rodents.

Then, the researchers went to compare their results. They likened the hole’s position and orientation across these many species.

Human Skull Shares Foramen Magnum Features With Other Mammals

According to the study, this large hole is a common element across more than just one species. More exactly, it was noted both in humans and primates. Furthermore, it was also observed in kangaroos, jerboas, and springhares. All of these species have a more forward-positioned skull hole. At least when compared to their quadrupedal closest relatives.

“The question of how bipedalism influences skull anatomy keeps coming up partly because it’s difficult to test the various hypotheses if you only focus on primates.”

This is all according to Chris Kirk. He is an anthropologist part of the University of Texas at Austin and research member. Kirk also pointed out the following fact. He claims that the evidence linking the skull evolution to bipedalism grows if the animal spectrum is increased. According to him, research should look at the “full range of diversity across mammals”.

This will show that the two factors go hand-in-hand and influenced one another. Russo states that, for the study, the team used multiple skull metrics. She considers this “convincing evidence” as it helped capture a “real phenomenon”. That of the forward-shifted foramen magnum across several mammalian species.

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