An article in the journal “PLOS ONE” describes a research carried out on a femur found in China, in a cave called Maludong, which means Red Deer Cave. This bone, as well as the remains of the skull, show a mixture of ancient and modern anatomical features. The dating of the femur is approximately 14,000 years old but its appearance is similar to that of Homo habilis, a species thought to be extinct about 1.5 million years ago, and early Homo erectus, appeared about 1.9 million years ago.

This fossil femur was discovered in 1989 but was left in a Chinese museum without ever being studied. It’s only recently been examined by a team led by Associate Professor Darren Curnoe from UNSW Australia (The University of New South Wales) and Professor Ji Xueping from the Yunnan Institute of Cultural Relics and Archaeology (YICRA, China).

Test results have immediately caused arguments because relatively young bones are similar to those of very ancient species. In recent decades, studies of the ancient hominids are giving many surprises but it’s sometimes difficult to identify a speciman’s species, especially when only very few bones are found as it happened in the Red Deer Cave.

In recent months, the discovery of fossils of a possible human species still unknown that was called Homo Naledi caused discussions and in that case there were many bones to be examined. A problem in the research on Homo Naledi was the absence of references to the bones’ age, requiring further examination, even of the destructive type.

The bones found in the Red Deer Cave were dated indirectly, through an analysis of sediments in which they were discovered. According to the radiocarbon exam their age is between 13,590 and 14,310 years. It’s a time when paleontologists didn’t expect that there were hominids with such ancient characteristics.

The only fossils comparable to the Red Deer Cave ones are those called Homo floresiensis and nicknamed Hobbit discovered in 2003. They had in common with those found in China the small size as the hominid of the Deer Cave Rossi must have weighed around 50 kg (110 lbs).

In short, it’s possible that hominids with very ancient characteristics lived in China as well but it’s also possible that they were the result of cross-breeding between different species of hominids. One of the most interesting results obtained in recent years in the study of hominids is the increasing gathering of evidence that many hominids cross-bred with each other over and over again.

When there are hybrids, sometimes individuals out of the ordinary are born with characteristics determined by the shuffling of their parents’ DNA. This is one of the possibilities for the hominids of the Red Deer Cave but if that were the case a mystery would remain because it still would mean that different species of hominids lived in the area in relatively recent times.

To get some answers DNA test would be needed. The researchers tried to extract DNA from the femur but so far without success. It’s possible that the genetic material inside the bone was destroyed because it was put on a fire by the other hominids who lived in the cave. The efforts will continue to try to figure out who the hominids who lived in Red Deer Cave really were.