Scientists in the Philippines have this week published a paper on the discovery of a previously unknown species of ancient human.
The specimen, which has been named Homo luzonensis, was found in a cave on Luzon Island in The Philippines - and its discovery has thrown quite the curveball into our previous understanding of human evolution, as it is believed they coexisted with our ancestors.
The remains have been dated to 50,000-67,000 years ago, meaning that this species of human had existed outside of Africa (where our ancestors are believed to have dispersed from) possibly before early Homo sapiens had left the continent.
"We now know that it was a much more complex evolutionary history, with several distinct species contemporaneous with Homo sapiens, interbreeding events, extinctions," said Florent Détroit, one of the paper's authors. "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 site did not produce an intact skeleton, but the remains that were found - seven teeth, two hand bones, three foot bones and one thigh bone - are believed to have belonged to two adults and one child, and yielded enough information for scientists to deduce some key information about Homo luzonensis.
The size of the teeth suggest that the early humans would have stood less than four feet in height, and the curved toe bones would indicate that they had an ability to walk upright on two legs, but also that they were adapted to climb trees.
"Maybe the way they were walking was distinct," said Détroit. "This is something we plan to work on in the near future."
Researchers have found that the remnants closely resemble another ancient species, Homo floresiensis (sometimes described as a "Hobbit"), which was also found in south-east Asia and believed to have lived around the same period.
As exciting as the discovery is for researchers, there are a number of questions and mysteries that remain unanswered on account of there being so little evidence to analyse. The most troubling one being: how did these ancient humans arrive on Luzon Island? The land is not believed to have ever been connected to the mainland, which suggests that the ancient species was somehow able to traverse the sea - either deliberately, by some sort of raft, or perhaps accidentally, by a tsunami or some other natural event.
"Arrival by accident … is favoured by many scholars, but this is mainly because of arguments like ‘Homo erectus were not clever enough to cross the sea on purpose,'" said Détroit. "But the fact is that we have now more and more evidence that they successfully settled on several islands in the remote past in south-east Asia, so it was probably not so accidental."
For many in the field, this discovery is not entirely surprising, however.
One scientist, Professor Chris Stringer, from the National History Museum, said: "After the remarkable finds of the diminutive Homo floresiensis were published in 2004, I said that the experiment in human evolution conducted on Flores could have been repeated on many of the other islands in the region.
"That speculation has seemingly been confirmed on the island of Luzon... nearly 3,000km away."
If these recent findings are any indication of what is yet to come, it could be that we are yet to discover key information about our origins as a species - and who knows where those realisations will take us.
