It's the first rule of the nightclub - and it appears fish adopt it too. When it comes to reeling in a mate, scientists say fish surround themselves with ugly friends - because they look so good by ...

To see how harassment affects the female social bonds, the researchers put each of three pairs of small guppies (a random mix of females and small males) into a transparent cylinder, with all ...

Their brightly-coloured skin and beautiful fins have made them a favourite pet. But woe betide anyone who releases their guppy fish into the wild for these tropical creatures can upset the other ...

Best girlfriends might never let a man come between them — unless they're Trinidadian guppies. Among these fish, the presence of a harassing male can disrupt female social networks, causing ...