Asked by: Ron Johnson, Harlow
Bananas are a cultivated form of plantain. In the wild, plantains are evolved to disperse their seeds mainly by birds and bats. While the fruit is developing it is protected by a thick skin that keeps insects out. As the seeds become ripe, the fruit absorbs water from the inside of the skin, which causes the skin cells to collapse and lose rigidity. This makes it easier for animals and birds to tear them open and carry off the little seeds along with a mouthful of banana.