Hymie sent me a link to an article on "A New Germ Theory" that is fascinating. One of the more controversial points Paul Ewald makes is that homosexuality may be caused by a virus rather than a genetic component. If it were genetic it would not be as common as it is because homosexuals only reproduce about 20% of the time so the genes that cause it would have disappeared over time. He also makes the same point about schizophrenia being caused by a virus rather than genes because people with schizophrenia don't reproduce as often as non-schizophrenics. Unlike his wishful thinking about homosexuality several scientists believe they may have discovered a virus which causes schizophrenia. It's a fascinating read which provoked more questions than it answered.