PRINCETON UNIVERSITY PRESS, FEBRUARY 2016Human life has changed immensely over the millennia, but never so much or so quickly as in the last century. For almost the entire 200,000-year existence of our species, Homo sapiens, biology controlled us. We gathered fruits, nuts, and plants, hunted and fished for the animals that were available, and like the wildebeest or zebra, we moved on when resources ran low. Even after the advent of farming and civilization, and the development of cities, we were still very vulnerable to the whims of the weather, and to famine and epidemics.
But in just the last hundred years or so, we have turned the tables and taken control of biology. Scourges such as smallpox, a virus that killed as many as 300 million people in the first part of the 20th century (far more than in all wars combined) was not merely tamed, it was eradicated from the planet. Tuberculosis, caused by a bacterium that infected 70-90% of all urban residents in the 19th century and killed perhaps one in seven Americans, has nearly vanished from the developed world. More than two dozen other vaccines now prevent diseases that once infected, crippled, or killed millions, including polio, measles, and pertussis. Deadly diseases that did not exist in the nineteenth century, such as HIV/AIDS, have been stopped ...
