http://www.thestar.com/news/sciencetech/science/article/762699–gay-uncles-important-for-evolution-study-finds
Gay uncles command a vital role in evolution, a surprising new Canadian study reveals.
Dr. Paul Vasey, an evolutionary psychologist at the University of Lethbridge, based his findings on repeated study of the “third gender” fa’afafine in Samoa – men who live as women and are universally accepted in the island’s culture.
Fa’afafine are far more likely to care for and help their nieces and nephews than heterosexual men and women, the study found. But the same nurturing, altruistic behaviour wasn’t there for children who weren’t relatives.