In evolutionary terms, homosexuality presents something of a paradox. According to Darwin, any trait that makes an animal less likely to reproduce will die out in a few generations, yet the percentage of people born gay or lesbian remains more or less constant.
Now researchers at the University of Portsmouth believe they may have found the evolutionary reason for homosexual behaviour: it helps us bond with people of the same sex.
A study of predominantly heterosexual men and women found that people with higher levels of the hormone progesterone are more likely to have homoerotic thoughts.
Read more at telegraph.co.uk
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