My 9-year-old daughter has stumped me with a question. She asked why the shape of eyelids differ in different races. She used the example of Japanese versus Caucasian people. Any thoughts?
• The shapes of eyelids, along with other physical features, are the result of evolution – the selecting and deselecting of various traits through time.
A mutation, or random change, in a gene can result in an inheritable physical characteristic that can be beneficial, harmful or neutral. A beneficial mutation may be selected for, so that it spreads from parents to children through a population in a relatively short time in…
