A new human species called Homo luzonesis has been discovered by a team led by University of the Philippines associate professor Armand Salvador Mijares from fossils excavated in Callao Cave in Peñablanca, Cagayan.
They included our own species, H sapiens, and Neanderthals, both living in Europe and western Asia, the Denisovans in Siberia, and the diminutive H floresiensis -nicknamed "hobbits" - from Indonesia.
The fossil bones and teeth found about 3 meters (9.8 feet) below the ground in the cave show they belonged to small-bodied people.
"Homo luzonensis is one of those species and we will [increasingly see] that a few thousand years back in time, Homo sapiens was definitely not alone on Earth". The new species raises many questions, including who were its ancestors and how did it move? Bones of deer and related animals were found in the area, some with cut marks, suggesting they were butchered although there were no stone tools or sharp implements found in the immediate area where the human fossils were dug up, Mijares said. "This combination of Homo-like traits with australopith-like hands and feet is the same overall pattern you see with Homo floresiensis, but with a different combination of features". "I believe that the designation of a new species is appropriate".
In addition, H luzonensis had toes identical to those of Australopiethecus, a primitive species that lived in Africa at least two million years earlier. Although it seems unlikely that enough hominins might raft to an island this way at roughly the same time to set up a breeding population, "monkeys did it from Africa to South America", Tocheri said.
It is also a mystery as to how the species reached Luzon island since it has never been connected to the mainland with a land bridge.
One theory holds that the peculiar features of luzonensis and its island cousin floresiensis could be the result of their habitat, with the unique and isolated surroundings prompting them to evolve characteristics reminiscent of their ancient forebears.
The sole representative of the first wave was thought to have been Homo erectus, which spread across the globe more than 1.5 million years ago. However, there are hints Homo erectus was not the only globe-trotting hominin of its time - last year, stone tools were found in China that were 2.1 million years old, "and there are no known Homo erectus fossils that old", Tocheri noted. That's something that hasn't even been considered possible before now.
The scientists detailed their findings this week in the journal Nature.
"We completed the comparisons and analyses, and it confirmed that this was something special, unlike any previously described species of hominins in the homo genus", added Detroit, a palaeoanthropologist at France's Musee de l'Homme.
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