Equality of opportunity has long been an American ideal, and the expansion of opportunity to women and minorities in the last half century has been a major success. But other obstacles to advancement remain, and recently, socioeconomic inequality has actually increased. The United States now has less social mobility than more other wealthy nations; it can and must catch up by following their lead.

Drosophila transformed developmental genetics and cell biology. Now the fruitfly is poised to help biologists decipher how the brain works.