Scientists look at a series of old teeth that were first discovered in the 1970s, but were thought to have originated more than 200,000 years ago, on the assumption that they could reveal a previously unknown human family member.
The four teeth were first discovered in the Yanhui Cave, located in Tongzi Province in southern China, between 1972 and 1983.
At the time, they were classified as Homo erectus, a primitive human species that could walk upright and dates from 1.8 million years ago.
Now, a team of researchers from the Centro Nacional de Investigacion sobre la Evolucion Humana (CENIEH) believe that the teeth may have originated from Homo erectus or their more advanced counterpart, Neanderthals, or possibly another mysterious, hybrid group.
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Scientists look at a series of old teeth that were first discovered in the 1970s, suspecting they could reveal a previously unknown human family member
To reach this conclusion, the researchers used modern methods such as geometric morphometric analysis, which mainly investigates the change of shape, and Micro-Computed Tomography, or X-ray imaging in 3D.
Researchers said the teeth go back to around 172,000 to 240,000 years ago.
As part of their analysis, they compared Tongzi teeth with hominims from the same chronological period – the later part of the Middle Pleistocene – and the surrounding areas of East Asia, according to the study.
While looking at many comparative examples, the researchers not only know exactly where the teeth belong.
Scientists believe that the teeth can be linked to Homo erectus (reconstruction, pictured) or the Neanderthals. Without more fossilized evidence, however, they cannot really be sure
The teeth were first discovered in the Yanhui Cave, located in Tongzi Province in southern China, between 1972 and 1983. Scientists don't know exactly who the teeth are
In an effort to find out their origins, the researchers looked at the structures and patterns of the Tongzi teeth, according to National Geographic.
They also compared the teeth with contemporary tooth samples from East Asia, but also other regions, including West Asia, Africa and Europe.
It turned out to be even more puzzling when it turned out that the dentin, or tissue under the enamel, did not have the same folds as Homo erectus, National Geographic reported.
Depicted is Jose Maria Bermudez, one of the co-authors of the CENIEH study
Instead, the teeth had more simple features that were similar to those in Neanderthals, but they were still not a perfect combination.
A possible theory is that the teeth can come from the ancestors of Denisovan, a mysterious hominopopulation that separated from the Neanderthals about 400,000 years ago.
The teeth had some similarities to the Denisovans tooth fossils, but they were not placed in the same spot in the mouth, making it difficult to draw a definitive conclusion.
& # 39; An abundant amount of genetic information has been collected from the Denisovans, but there are few fossil remains, & # 39; CENIEH explained.
& # 39; Therefore, both their physical appearance and their identification in the fossil record remain a mystery. & # 39;
Another possibility could be that the teeth originated from a hybrid of two different hominims.
The teeth are thought to have originated from 172,000 to 240,000 years ago. They were found in the Yanhui Cave, in the Chinese country of Tongzi in the province of Guizhou (photo)
For example, if the Denisovans crossed the road with Homo erectus, they could have been crossed to make the group that produced this particular tooth sample, National Geographic noted.
Until they can get hold of more fossilized evidence, the origin of the teeth remains unclear.
& # 39; More genetic and fossil discoveries would be needed to evaluate the taxonomy of the non-erectus populations of the Middle Pleistocene, such as the Tongzi hominids, which could be good candidates for Denisovan's ancestors, & # 39 ; said Maria Martinon-Torres, one of the co-authors of the study.
WHEN HAVE HUMAN FORWARD FIRST BEAUTIFUL?
The timeline of human evolution can be traced back millions of years. Experts estimate that the family tree goes as follows:
55 million years ago – First primitive primates evolve
15 million years ago – Hominidae (great apes) evolve from the ancestors of the gibbon
7 million years ago – First gorillas evolve. Chimpanzee and human descent later diverge
A representation of a Neanderthal is shown
5.5 million years ago – Ardipithecus, early & # 39; proto-human & # 39; stock features with chimpanzees and gorillas & # 39; s
4 million years ago – Monkeys like early humans, the Australopithecines appeared. They had brains no bigger than those of a chimpanzee, but other, more human traits
3.9-2.9 million years ago – Australoipithecus afarensis lived in Africa.
2.7 million years ago – Paranthropus, lived in forests and had huge jaws to chew
2.6 million years ago – Hand axes become the first major technological innovation
2.3 million years ago – Homo habilis first thought to have appeared in Africa
1.85 million years ago – The first & # 39; modern & # 39; hand appears
1.8 million years ago – Homo ergaster begins to appear in fossil record
800,000 years ago – Early people control fire and create fireplaces. The size of the brain is increasing rapidly
400,000 years agO – Neanderthals appear for the first time and spread across Europe and Asia
300,000 to 200,000 years ago – Homo sapiens – modern people – appear in Africa
50,000 to 40,000 years ago – Modern people reach Europe