Your fingers may hold a secret of human brain evolution

Researchers are investigating the 'estrogenized ape hypothesis,' which suggests that prenatal estrogen exposure influenced human brain evolution. By measuring the ratio of index to ring finger lengths in newborns, scientists found a correlation between higher estrogen exposure and larger head circumference in boys.
Why it matters
Understanding the biological drivers of human brain evolution provides deeper insight into our species' development and cognitive origins.
Human evolution is closely associated with the development of a much larger brain. New research suggests that greater exposure to estrogen before birth may have contributed to that expansion, and that a possible trace of this hormonal influence can be seen in the relative lengths of a person's fingers.
The report summarizes evolutionary biology research objectively.
Get smarter about the news
Sign up free for a feed built around what you actually care about, Dive Deeper research on any story, and the full text of every article.
Create free accountAlready have an account? Sign in