Coyne describes on page 167 an interesting study done in 1998 by Burley and Symanski in which they tried to manipulate sexual selection among finches by creating a new and entirely novel trait among males to see if females liked it (this is different than merely exaggerating a preexisting feature). They glued a white feather pointing vertically on the heads of males. As it turns out, the females liked it and preferred these artificially modified males! Human body modifications also sometimes result in greater mate attraction. Breast implants, tattoos, and hair styles are all well known examples.
From pages 210 to 220 Coyne provided a very interesting description of the genetic differences between us and our nearest living relatives, and the genetic differences among humans today. While the differences that separate us from chimps are actually substantial when one understands how to interpret the genetic information, the differences among human populations are comparatively nonexistent. There is more variation within races than between them.
Now to the more philosophical problems, which Coyne tackles in the final chapter. While there is research suggesting that "evolution can favor genes that lead to cooperation, altruism, and even morality." Coyne unequivocally states that it is impossible to derive meaning, purpose or ethics from evolution, "It can't tell us what to do, or how we should behave." On pages 230-231 he writes:
The world still teems with selfishness, immorality, and injustice. But look elsewhere and you'll find innumerable acts of kindness and altruism. There may be elements of both behaviors that come from our evolutionary heritage, but these acts are largely matters of choice, not of genes... Evolution tells us where we came from, not where we can go. And although evolution operates in a purposeless, materialistic way, that doesn't mean our lives have no purpose. Whether through religious or secular thought, we make our own purposes, meaning, and morality.That about says it. Evolution gave us the raw materials, and we are active agents in the shaping of our future. We choose which impulses to act on and which to suppress. It is a process of continual growth and change.