No Evidence That the Shift to Farming Made Males and Females More Physically Similar
Published:10 Jun.2021 Source:PLOS
Scientists have proposed that males and females started to become more similar in size and shape after the origin of farming due to natural selection. However, a new evolutionary and genomic analysis by George Perry of Pennsylvania State University and colleagues, published in the journal PLOS Genetics, finds no evidence that this occurred.
The males and females of many species often have slightly different sizes and shapes -- think lions and lionesses, for example. The same is also true for humans, with adult males being slightly taller and heavier on average than females. Some scientists think that the differences between the sexes used to be greater, but that the shift to farming and a more equal division of labor about 10,000 years ago created evolutionary pressure that pushed males and females to become more similar. Others, however, think that any changes that have occurred in that time are just due to chance.