Brains are the New Brawn in Human Evolution

Over the years, humans have traded in brawn for better brains. In today's society, big muscles simply aren't as important as a good set of smarts.

A recent study conducted by researchers at Shanghai's CAS-MPG Partner Institute for Computational Biology showed that accumulation of metabolites grew faster in brains and muscles throughout the course of human evolution. These small molecules of sugar, vitamins, amino acids and neurotransmitters, are produced during metabolism and important during DNA and protein synthesis.  

"Metabolites are more dynamic than the genome and they can give us more information about what makes us human," said Khaitovich, via a press release. "It is also commonly known that the human brain consumes way more energy than the brains of other species; we were curious to see which metabolic processes this involves."

Based on an analysis of 10,000 metabolic molecues, researchers said they believe that humans switched energy-consumption between muscles and brains that helped many acquire better cognitive skills, while others built stronger muscles, but weaker brains. 

The research team conducted several tests on chimpanzees, macaques, university students and even professionals. Findings showed that time was responsible for weak muscles for better brains in humans. 

Researchers hypothesize that weak muscles were the price that many humans paid for better brains.

"Our results suggest a special energy management in humans, that allows us to spare energy for our extraordinary cognitive powers at a cost of weak muscle," summarized Dr Kasia Bozek, the lead author of the study. 

More information regarding the findings can be seen via the journal PLOS Biology.