Molly no mates 'thrives on sex with strangers'

A SPECIES of fish which has survived for 70,000 years despite having no males to mate with is defying the laws of evolution, say city scientists.

Amazon Molly fish, which are all female and are found in rivers in Texas and Mexico, interact with males of other species to trigger reproduction. However, no male DNA is passed on to the offspring.

University of Edinburgh researchers say the fish ought to have become extinct within the last 70,000 years. Dr Laurence Loewe, of the university's School of Biological Sciences, said: "This fish really has something special going on and some special tricks exist to help this fish survive.

"Maybe there is still occasional sex with strangers that keeps the species alive."