How Evolutionary Biology Explains Why we Get Sick
Medical research has focused, properly and powerfully, on how the body works and what part of the mechanism is awry in a person who has a disease. Evolutionary medicine adds a whole new perspective by asking a new question: Why has natural selection left our bodies vulnerable to disease? Why do we have wisdom teeth, narrow birth canals, narrow coronary arteries, and limited abilities to control infection and cancer? The old answer was that natural selection is just not strong enough to make the body better. This is only one of six reasons why we get sick. Some problems are because we live in an environment very different from our ancestors. Others reflect trade-offs that prevent perfection in any trait. Especially interesting are problems that result because of genes that benefit their own futures at a cost to our health. Responses like pain, fever and cough are not diseases at all, but useful defences shaped by evolution. Randolph Nesse is one of the world’s preeminent researchers in the relatively young field of evolutionary medicine. By integrating evolutionary thinking into the health sector, he is transforming medicine in fundamental ways. At Falling Walls, Randy demonstrates how natural selection can explain not only why so many things in our bodies are working perfectly well, but also why some of our functions are hard-wired to fail. And how this knowledge can improve human health.