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TagClint Penick

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Researchers Still Puzzled: Why Did Human Brains Shrink?

Human brain volumes decreased by 10% in the last 40,000 years, coinciding with spectacular intellectual achievements

We conventionally associate big brains with intelligence. But the evidence from the present day and from history is uncertain: It’s something of a well-known secret among anthropologists: Based on measurements of skulls, the average brain volume of Homo sapiens has reportedly decreased by roughly 10 percent in the past 40,000 years. This reduction is a reversal of the trend of cranial expansion, which had been occurring in human evolution for millions of years prior… For instance, a 1988 Human Biology paper analyzed more than 12,000 Homo sapiens crania from Europe and North African. It showed cranial capacity decreased in the past 10,000 years by about 10 percent (157 mL) in males and 17 percent (261 mL) in females. A similar…