ARI SHAPIRO, HOST:
A very strange species of human apparently lived on an island in the Philippines as recently as 50,000 years ago. This creature was probably less than 4 feet tall with several ape-like features. But as NPR's Christopher Joyce reports, scientists believe it's a human relative.
CHRISTOPHER JOYCE, BYLINE: Archaeologist Armand Mijares was digging in a cave on the island of Luzon 12 years ago and found a toe bone. It did not look like a modern human toe bone.
ARMAND MIJARES: We know already there is something peculiar about this bone.
JOYCE: Mijares, who's with the University of the Philippines, was on a team looking for bones of early humans. They kept digging for four more years. Then they hit pay dirt - more toe bones and finger bones, part of a thigh bone and seven teeth. And none looked like they belonged to modern humans.
MIJARES: We agreed that this could be, probably, a new species.
JOYCE: Discovering a new species of ancient human is a career-maker in anthropology, or breaker, if you're wrong. So the team spent another eight years studying the bones and teeth. They were from three individuals living sometime between 50,000 and 67,000 years ago. Writing in the journal Nature, the scientists call them Homo luzonensis, after the island. And, says paleoanthropologist Shara Bailey, they were pretty strange.
SHARA BAILEY: We tend to define species based on unique combinations of traits, and that seems to be what's going on here, although I have to say I'm really super surprised because you have some very primitive traits.
JOYCE: One toe bone is so curved, it looks like it belongs to a tree-climbing ape-like creature that lived millions of years ago. Some of the teeth look fairly modern, more like ours, but others are very primitive. Bailey, at New York University, calls it a mosaic species.
BAILEY: I think it just opens up all these - so many new questions, so it's exciting.
JOYCE: One question is, were these creatures related to the Hobbits? No, not the movie characters. Hobbits is a nickname for another tiny primitive human species that lived on an Indonesian island up until 50,000 years ago. Also called Homo floresiensis, the Hobbits were discovered 15 years ago, and they, too, had a weird mix of ape-like as well as human-like bones.
Paleoanthropologist Matt Tocheri at Lakehead University in Canada is an expert on the Hobbits.
MATT TOCHERI: And here we are not that much later, and now we've got a similar thing popping up on an island in the Philippines. They're living out on these oceanic islands. And they're essentially there at the same time our species is, you know, conquering the world, if you will.
JOYCE: These two throwback species in Southeast Asia also raise new questions about the migration of human ancestors out of Africa. The standard view holds that the first to leave Africa was a large-bodied, fairly big-brained human called Homo erectus as long as 2 million years ago. They spread through Asia and Europe. It is possible they got to these islands, where they somehow evolved into these more primitive forms.
But Tocheri says maybe there's another explanation - a different migration out of Africa by some more ape-like species, one that settled in remote parts of Asia.
TOCHERI: That's where it gets exciting because if it's true that other species of early Homo also made it out, then it just - it means that what we're going to be finding in Asia is going to be even more complex and more interesting than we ever dreamed of.
JOYCE: Then there's this riddle. How did they cross hundreds of miles of ocean? But questions aside, one thing is clear. Early humans came in a lot more shapes and sizes than scientists once thought. Christopher Joyce, NPR News.