As humans have come to dominate the planet, they have modified not only their own evolutionary course but also that of fellow species. Although such alterations help us survive, their unintended evolutionary consequences often produce harmful results that threaten our well-being.
For the vast majority of the history of our kind we were in some ways no more sophisticated than crows, which use sticks to poke around in promising holes. Eventually, of course, we discovered fire and invented stone tools, which then led to guns, pesticides and antibiotics. Using these tools, we encouraged the survival of favorable species such as wheat and yeast needed for beer and cows for meat and milk—a garden of delights.