A team of archeologists has pieced together bone fragments to reveal what is, apparently, a new species of human.
The discovery of a foot bone lodged in the Callao Cave, a limestone grotto on the island of Luzon in the Philippines, gave the researchers, led by the University of Philippines and the National Museum of Natural History in France, the first inkling that they were onto something.
Although they recognized it was a metatarsal bone dating back to 67,000 years ago, they couldn’t quite place what homo species it belonged to. So, they carried on digging. They found more foot bones, a thigh bone, hand bones, and teeth. The small collection of 13 items taken from at least three ancient individuals was enough to convince them they had stumbled across a new species: Homo luzonensis.
The size and shape of the bones stood out. Homo luzonensis’ upper molars are smaller and smoother. Unlike our own teeth, they lack the curved grooves on the surface and the size doesn’t seem to fit in with other species like the Neanderthals, Denisovans, or Homo floresiensis.
World's oldest URL – fragments 73,000 years old – discovered in caveREAD MORE
“In terms of absolute tooth size and premolar–molar proportions, H. luzonensis shows a pattern that is not seen elsewhere in the genus Homo,” the researchers wrote in a paper published in Nature on Wednesday.
The other bones seem to share some similar characteristics with other species, however. For example, one foot bone is curved like the ones spotted in Australopithecus afarensis, an early humanoid species estimated to have existed more than three million years ago. The bend suggests that maybe the Homo luzonensis’ were climbers.
The size of the finger bones are comparable to Homo sapiens, but outside the ranges for other homo species. The thigh bone is a fragment of a left femur bone. According to micro-CT scans, it belonged to a body that wasn’t fully grown yet. Another previous discovery of stone tools and evidence of a butchered rhinoceros point to the existence of a small-bodied homo species that may have lived on the island more than 700,000 years ago.
The latest shards of bone are the earliest signs that humans started populating the Philippines as far back as 67,000 years ago. The timing shows that Homo luzonensis roamed Earth at the same time as Homo sapiens, Neanderthals, Denisovans and Homo floresiensis. It’s unknown if Homo luzonensis came into contact with any of the other species as scientists could not extract any DNA from the samples. ®