Evidence of New Human Species Discovered in a Cave in the Philippines

There were once many human species, but today there is only one; modern humans, Homo sapiens. However, the human family tree is growing. Researchers working in a cave in the Philippines claim to have found a new, previously unknown species to add to human history.

Remarkably this hominin was probably less than four feet high and had some of the characteristics of modern people but also anatomical features from much earlier hominins. It is believed that the discovery will transform the understanding of our evolution.

New humans found in the Philippines

In recent years there have been a series of finds of early humans in the Philippines. The latest  was made by archaeologists as they were digging in the ‘rocky floor of Callao Cave on Luzon island’ according to History.com. A team of experts found a number of fossils that are unlike anything else in the world. They were unearthed by a team of experts led by Professor Philip Piper, from the Australian National University.

The excavation site at Callao Cave. (Image: © Callao Cave Archaeology Project)

According to the Daily Mail, “the fossil remains included adult finger and toe bones, as well as teeth.” The femur bone of a juvenile was also unearthed. The remains are estimated to be about 50,000 years old, at a period of time in the Pleistocene when several human species co-existed on the planet. A preliminary examination of the remains indicated that they came from an ‘unknown species of hominin’ according to Haaretz.

• 11 Mysterious Human Species That Most People Don’t Know Existed
• Fossil Find Reveals New Species of Early Human - Origins of Modern Man Gets Crowded

The five upper teeth found belonged to a single individual of previously unknown hominin, provisionally named ‘Homo luzonensis’. The have a strange mix of Australopithecine and modern features. (Image: © Callao Cave Archaeology Project)

A new human relative?

The stunning discovery has been provisionally named Homo luzonensis. The new species had some of the same characteristics of modern humans, in particular, its molars. However, they also had characteristics of a far earlier species namely of Homo australopithecus. This hominin was the ancestor of many human species including Homo erectus and lived between 2 and 3 million years ago. The Daily Mail reports that ‘hand and feet bones, are remarkably Australopithecine-like’.

Despite these similarities, the shape of the tooth and the anatomy of the feet shows that they are a unique human species. The slight but significant difference are such that taken together they strongly indicate that Piper and his team have unearthed a new species. What is most striking about the new species was their estimated height, possibly just under four feet.

One of the teeth found in Callao Cave (Youtube Screenshot)

Connection to the Hobbit?

The height of the new humans was determined by the size of the tooth and the other bones. However, more evidence is required to confirm this. If the size is confirmed, it is raising the possibility that the hominins are somehow related to another species found in the Indonesian island of Flores. This hominin is Homo floresiensis and stood under four feet high. Because of their diminutive stature, they are popularly known as the Hobbit.

An examination of the foot bones found morphological features that come from both earlier and later hominins. This could indicate that they had a particular way of walking.  According to Science Mag, the human had ‘long, curved fingers and toes’. This means that it was as comfortable scrambling up trees as walking upright.  This would seem to suggest that it ‘might have descended from an earlier human relative, H. erectus, that somehow crossed the sea to Luzon’ reports the WRAL.com.

• Age of the Wise Men: What Distinguishes Homo Sapiens from the Other Great Apes?
• Five Things We Learned About Our Human Origins in 2018

The proximal foot phalanx of Homo luzonensis. Notice the longitudinal curvature of the bone, which suggests that this species was adapted to climb trees.  (Image: © Callao Cave Archaeology Project)

According to History.com ‘human evolution was clearly much more complex’ in Asia than previously assumed. It seemed that  H. erectus in evolved in the region into new species such as that possibly found in Luzon. It appears that the human evolved in a unique way on the island of Luzon, very different from those on mainland Asia.  Science Mag reports that many experts “suspect the islands of Southeast Asia may have been a cradle of diversity for ancient humans.”

New theory on human evolution

The find is casting doubt on the accepted theory of how humans evolved and spread out over the globe. The first wave of our relatives to leave Africa was made up of H. erectus and the second wave was H. sapiens. It was thought that H. erectus settled in Asia and it was the only human in Asia until the arrival of modern humans. The discovery of H. luzonensis, along with the earlier discovery on Flores have upturned this theory.

More work needs to be done to establish if the human remains found on Luzon are from a new group of hominins. At present, there are approximately 12 human species recognized but there is no agreement as exactly how many have been identified. It seems likely that the humans whose bones were found in the Callao Cave may be another one of our relatives and will add greatly to our understanding of human evolution.

Top image: Callao Cave, Luzon Island, Philippines where the bone and teeth of the new human species were found.                Source: Supplied courtesy of © Callao Cave Archaeology Project

By Ed Whelan