Our human ancestors from thousands of years ago has some very different facial features than we do today. They looked more aggressive, a trait that was enhanced by their fierce-looking eyebrows. Hominins from 200,000 to 600,000 years ago had a more pronounced brow ridge. This made them look aggressive in order to inspire dominance. According to researchers, those were similar to how antlers work for a male deer. However, those times are long gone and now, humans have evolved to display a smooth and mobile forehead along with hairy eyebrows.
But what happened in-between? How did the very pronounced brow ridge transform into expressive and mobile eyebrows? Researchers have previously proposed an answer for this. In the past, the brows ridge served as a filler for the space between the eye sockets and the brain case. It was also a stabilizer for the skull to be able to chew on the very hard foods that our ancestors ate. However, a new study, which the journal Nature Ecology and Evolution recently published, something else might have happened. That brow ridge was actually a sign of dominance and aggression, not a support for the skull.
The evolution of eyebrows on the human face
According to researchers, over the past 100,000 years, the human face became smaller and smaller. When the forehead began smoothing, we also began growing hairy eyebrows. It was something needed for our developing communication skills. The fact that eyebrows are able to express so many emotions helped the increasing populations communicate even through a language barrier.
According to Paul O’Higgins, the senior author of the study, it seems that the ancient and prominent brow ridge was not a support for the skull. Instead, it was actually a tool to communicate aggression and dominance. As survivability relied more and more on communication, that brow ridge slowly disappeared. This is most likely the reason why humans today have eyebrows and not a prominent and scary brow ridge.
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