text: The avocado tree is 'transgender' and has overnight sex changes, a botanist has discovered. Professor John Warren discovered avocado trees switch from male to female in a matter of hours. Professor Warren, based at the University of Aberystwyth, Wales, said the avocado tree displays 'unique flowering behaviour'. He found that during the day the trees, which grow in tropical and Mediterranean climates, flower with their 'female parts' ready to be pollinated by bees. Professor John Warren discovered avocado trees switch from male to female in a matter of hours . The flowers close for the night and then the next morning they reopen - but now they use their 'male anthers' to spread their pollen. Professor Warren said: 'The whole elaborate exercise seems to have evolved to increase the chances of cross-pollination, while limiting the amount of self-pollination. 'The trees are usually successful in avoiding the 'sin' of inbreeding.' Professor Warren has written about the avocado in his book called the Nature of Crops. The botanist, from the University of Aberystwyth, pictured, said the plants limited the amount of self-pollination .
target: Professor John Warren discovered avocado trees switch gender in hours .
  The botanist said the tree displays 'unique flowering behaviour'
  However, trees are usually successful in avoiding polinating themselves .