Eyebrows often signal disbelief, amusement, curiosity, dismay. But it wasn’t always that way. Early humans had thick, bony brow ridges that were far less nimble than ours, incapable of expressing much. Scientists have long thought those brows served some structural purpose, like support for chewing prehistoric food. But when Ricardo Miguel Godinho, an evolutionary anthropologist at the University of York, made digital recreations of a skull believed to be 300,000 to 125,000 years old, he found no evidence that its brow ridges provided practical benefits. The findings suggest that the human brow has always been a primarily social tool.

Sea turtles find birth places years later

Sea turtles use the Earth’s magnetic fields to navigate back to the area where they were born decades earlier, said a study that used loggerhead genetics to investigate their travels. After swimming for years in a giant loop from nesting grounds in North Carolina and Florida to North Africa, the turtles find their way back to nest on beaches within about 40 to 50 miles of where they were born. The study suggests that the turtles learned their home beach’s distinctive magnetic signature, through what is called geomagnetic imprinting.

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