Human evolution, at first, seems extraordinary. How could the process that gave rise to slugs and oak trees and fish produce a creature that can fly to the moon and invent the Internet and cross the ocean in boats?

Consciousness turns out to consist of a maelstrom of events distributed across the brain. These events compete for attention, and as one process outshouts the others, the brain rationalizes the outcome after the fact and concocts the impression that a single self was in charge all along.

In culture after culture, people believe that the soul lives on after death, that rituals can change the physical world and divine the truth, and that illness and misfortune are caused and alleviated by spirits, ghosts, saints ... and gods.

For all the tribulations in our lives, for all the troubles that remain in the world, the decline of violence is an accomplishment that we can savor - and an impetus to cherish the forces of civilization and enlightenment that made it possible.

Climate change could produce a lot of misery and waste without necessarily leading to large-scale armed conflict, which depends more on ideology and bad governance than on resource scarcity.

But in most cases even the possibility that the correlations reflect shared genes is taboo.

Natural selection is not the only process that changes organisms over time. But is the only process that seemingly designs organisms over time.