In a careful paper, John R. Hibbing makes a strong case that political scientists—who have learned lessons from many other disciplines—need to make room for biology. While his paper is reassuring on many counts, two matters cause concern. First, Hibbing argues that the open acknowledgment of the biological basis of group differences would lead to greater tolerance. It is easy to adduce examples to suggest that it is unrealistic to expect that people, especially people with political concerns and objectives, will begin to focus on the diversity within groups rather than the differences between groups. Second, it is not clear the extent to which investigations into the biological basis of politics would illumine the great questions of political analysis.