Humans May Have a Surprising Evolutionary Advantage: Expressive Eyebrows
Scientists still aren’t sure why early humans had such weird skulls — or why we don’t
By Mary Beth Griggs
It’s one of the first things you notice when you look at archaic human relatives in a natural history textbook or museum. Just above the eyes rests an imposing feature, a prominent brow ridge that juts out above the eye sockets.
But why did many of our distant relatives have this distinct facial feature? Why don’t we have it anymore? Over the years, scientists have suggested plenty of solutions. There are hypotheses that it was a built-in shade from harsh sunlight, or helped shield eyes from rainwater or even fisticuffs. Maybe, researchers suggested, it kept hair or sweat out of an early hunter-gatherer’s peepers. Maybe it helped keep the face from experiencing too much strain when an early human bit down. Perhaps that extra slice of bone was just filler, taking up space between the brain and the face.
Mechanical function
In a study published this week in Nature Ecology & Evolution, researchers from the University of York decided to take a closer look at the latter two ideas. With software similar to what engineers use to model and test strain on…
