SLOTH

This species, discovered on the island on Escudo de Veraguas off the Carribean coast, shows how quickly the process of evolution can happen. The pygmy sloth has been isolated on its tiny island habitat for just 9,000 years - when rising sea levels cut the island off from the mainland. The sloths are slower and more placid than their mainland relatives and, remarkably, they can swim. They seem suitably adapted to their Caribbean island lifestyle. Pygmy sloths are less than half the size of a normal sloth and they only eat mangrove leaves - a low-nutirent diet that explains their diminutive stature. There are just 200 of them on the island so every mangrove tree counts for these vulnerable creatures. Decade of Discovery, a collaboration between Conservation International and the BBC's Natural History Unit, will be broadcast at 20.00BST on Tuesday 14 Decmber on BBC Two 

http://www.youtube.com/watch?v=lcfuRpcJNsU&feature=player_embedded