To Determine Whether the Differences Between the Human and Chimpanzee

Multiple Choice

To determine whether the differences between the human and chimpanzee genome are a result of natural selection or mutation and drift, geneticists compare synonymous and nonsynonymous substitutions. Genes that have evolved because of selection should show what pattern?

A) fewer nonsynonymous substitutions than synonymous substitutions
B) more nonsynonymous substitutions than synonymous substitutions
C) no difference in nonsynonymous and synonymous substitutions
D) There is too little information to answer this question.