Around 2.4 million years ago, humans experienced a mutation in gene MYH16, which led to smaller jaw muscles. This mutation allowed us to
A) develop more complex language skills.
B) devote more of the area of the skull to the brain.
C) change our diet, such as eating more meat.
D) use our hands rather than our teeth in food preparation.

Question

Quizplus · Accepted Answer

The MYH16 gene mutation allowed for smaller jaw muscles, which in turn allowed for a larger braincase and more space for brain expansion. This is known as the "expensive-tissue hypothesis" and suggests that the energy saved from smaller jaw muscles was redirected to fuel a larger brain, which allowed for the development of more complex language skills and other cognitive abilities.

Around 24 Million Years Ago, Humans Experienced a Mutation in Gene