Madagascar's Unique Wildlife Populations

NBCNews Science:

The mysteriously rich diversity of life on the isle of Madagascar might have arrived there in part on "floating islands" carried by ocean currents, researchers now say.

Madagascar, the world's fourth-largest island, is the sole home to a wide variety of animal species, most of which are thought to have reached Madagascar after plate tectonics separated it from Africa and other continents.

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But not all scientists have been convinced by this theory.

"There has been a great debate about rafting over at least the past 50 years," Samonds said. "While many authors have argued that dispersal events by terrestrial, land-dwelling animals across great distances of water are virtually impossible, others have argued that even unlikely events are certain to occur if the time elapsed is long enough, and that prevailing ocean currents could have aided these journeys."