(This is a news story I wrote for my Science Reporting seminar. Random as it is, it was so cool I just had to post it.)

A 70-year argument among scientists concerning lemurs and other furry inhabitants on Madagascar may be over, according to a study published in Nature in January. Scientists Jason R. Ali and Matthew Huber, from the University of Hong Kong and Purdue University, respectively, claim that the isolated collection of mammals that arrived to the island millions of years ago did so in almost cartoon-like fashion. They rafted in.

This theory was first proposed in 1940, though it had been previously dismissed as impossible. Paleontologist George Gaylord Simpson proposed that the lemurs, tenrecs, carnivorans, and rodents which showed up in Madagascar in distinct batches starting 60 million years ago floated unwittingly across the ocean channel on large logs or vegetation mats washed off eastern Africa. Other scientists disagreed, saying the area’s ocean currents rule out such a possibility and that the mammals must instead have walked across some sort of land bridge. But no one has been able to recreate a scenario where this is possible either.

The ocean bordered by Africa, Asia, and Australia flows in what scientists call a “supergyre,” essentially a big counter-clockwise swirl between the continents. Madagascar is located near the top-left portion of this giant current, which means the water flowing between the island and the African continent flows south and west. A raft launching from Mozambique, where scientists agree the Madagascan mammals originated, would be quickly swept away past the island.

However, the continents themselves are constantly migrating. Africa and Madagascar have drifted some 1,650 kilometers north in the past 60 million years. Using climate system models from the US National Center for Atmospheric Research, Ali and Huber took a look at various recreations of what Earth would have looked like in the days the lemurs and their cousins would have set sail. The scientists discovered that, unlike today, 60 million years ago Madagascar sat toward the bottom of the Indian Ocean gyre, meaning currents would swirl across the coast of Africa and back east toward Madagascar. Floating debris from Mozambique could reach Madagascar in less than a month. And if a tropical storm came around, currents would flow faster, allowing even more rapid transport.

Large floating “tree islands” have been known to wash off the African coast during storms, so it’s entirely possible that animals 60 million years ago washed away with them. Though rafting mammals clinging to logs while crossing hundreds of kilometers of ocean may sound like a scene from a Disney movie, it’s now the most plausible explanation scientists have for the Madagascan mammal phenomenon. The next big puzzle: Why are these lemurs so darn cute?

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