We have plenty of evidence for evolution, plenty of fulfilled predictions, and no pieces of evidence (e.g. Precambrian rabbits) that would have disconfirmed it. Scientists disagree on minor points, like the importance of genetic drift or the precise cause of the Cambrian explosion, but there's no controversy on the big ones. So why is it that people find evolution so hard to accept? Most of the opposition comes from religion. Creationists create fear of evolution by claiming that it robs us of purpose, causes us to behave "like animals," and sanctions the killing of those who are weaker than us.
None of this is true. Evolution is a description of how life changes over time; it says nothing about whether such change is good or bad. It tells us how things are, not how they should be. It's not somehow "wrong" to defy natural selection by caring for the weak—that would be like saying that it's wrong to defy gravity by jumping or firing rockets into space.
|Burn the heretics of our holy prophet Newton!|
The idea that support for evolution would make us behave "like animals" is a non-starter. Animals exhibit an endless variety of behaviors, many of them altruistic. Perhaps creationists think that evolution would cause us to act like rhesus monkeys, who will starve themselves before allowing one of their companions to experience an electric shock?
Of course, it's true that humans have behaviors that are hard-wired as a result of natural selection: that's the realm of evolutionary psychology. Coyne criticizes this field for venturing too far into speculation, but he suggests eating, sleeping, sex, parenting and the favoring of relatives as uncontroversially inherited instincts. Another such instinct, the relative promiscuity of men compared to women, might seem to validate creationist concerns. But this behavior exists whether we accept evolution or not—and humans have higher mental faculties to override these urges and societies that can shame the cheaters.
What about purpose, then? How can we go on living without the notion that we were created by a loving God? Simple: we make our own meaning. We can love our friends and family, enjoy art, food and sport, and revel in the wonders of our universe. While evolution says nothing about meaning, it does grant us a vast appreciation for the extraordinary journey our species has taken to get to this point.
I think it would be appropriate to bring this series to a close with the quote from Richard Dawkins that begins this chapter:
"After sleeping through a hundred million centuries we have finally opened our eyes on a sumptuous planet, sparkling with color, bountiful with life. Within decades we must close our eyes again. Isn't it a noble, an enlightened way of spending our brief time in the sun, to work at understanding the universe and how we have come to wake up in it? This is how I answer when I am asked—as I am surprisingly often—why I bother to get up in the mornings."