Remote islands offer sanctuary for some of the Planet's strangest and rarest creatures. The rare pygmy three-toed sloth enjoys a peaceful existence on an idyllic Caribbean island, while nesting albatross thrive in predator-free isolation.But island life always comes at a cost. On the Galapagos Islands, young marine iguana must escape an onslaught of deadly racer snakes the moment they hatch from the sand.On the Sub-Antarctic island of Zavodovski life gets more extreme still; every day 1.5 million penguins risk being battered against the rocks by fierce waves as they try to get on and off the island.