In a study of tropical guppies, scientists have found that the less attractive males have “better sperm”. The research revealed that colourful flamboyant-looking males “invest” in their appearance at the expense of their sperm quality.
A rather unusual but nonetheless interesting study of guppy reproduction. It seems there are two types of male guppies – those that have showy finnage and mainly use that to attract mates and less attractive males whose main tactic is to sneak up on females in order to mate with them. The investment in attractive, elaborate finnage and bright colours comes however at some cost in sperm effectiveness.
Flashy males get more females but have less effective sperm. The sneaker males get less females but have a higher chance of being successful with the few females they do mate with. Females mate with many males so the net result is a kind of arms race between the two types of sperm taking place within the body of female guppies. An astonishing thought.
Original BBC article is here – BBC News
Abstract of the scientific paper is here – The Royal Society