300,000-Year-Old Skull of ‘Maba’ Continues to Puzzle Scientists as It Does Not Match Any Human Species

Experts have been at work for years to carve out the path of human evolution. However, some pieces still don't fit the overall puzzle, like Maba 1, stated IFL Science. Maba 1 is a human fossil that was first detected by farmers in 1958 in China. Since then, researchers have been trying to understand where the fossil and, by extension, the individual fit into the human story. A detailed evaluation of the skull was recently conducted by a team of researchers who published their findings in the American Journal of Biological Anthropology. 

Examinations had previously revealed that the remnant was around 300,000 years old. To date, researchers have not been able to classify the skull and, by extension, the individual into any species. The fossil essentially contains parts of a skull along with a few facial bones. This incompleteness has made it difficult for researchers to categorize the individual. However, some past researchers claimed that the individual could have been a relative of Neanderthals, and hence the fossil is often also called 'Chinese Neanderthal.'

The skull was detected by farmers while digging for fertilizer in a cave sandwiched between two hills, stated John Hawks. These hills are called Lion Rocks (shizishan) and are present near the Maba village. These hills have now become part of a museum which also commemorates the discovery. Some researchers over the years have pushed back the origin of this fossil to 130,000 years ago.

The fossil has given experts many insights into the dead individual. Researchers think that Maba 1 was an adult at the time of death. The skull's general thickness, brow, and vault bones suggest that the individual was likely a man. The left side of the frontal bone exhibited evidence of some injury. This evidence is basically a semicircular depression accompanied by a raised bump. It is evident that the injury was healed, hence it could not have been the cause of death. 

The team associated with the new study undertakes an in-depth examination to resolve its mystery, according to IFL Science. This was the first time skull's inner parts like braincase, diploic vessels, and sinuses, have been analyzed extensively. The cranium's CT Scan revealed that the individual exhibits features from several archaic hominids. According to researchers, it is downright impossible to identify Maba 1 as only one of these hominids. 

Though the skull's features are unique, the inability to categorize it did not surprise researchers. The mid-Pleistocene period exhibited many species that did not fit particularly into one category. It seems that at that time, the species were going through a trial-and-error process in terms of adaptations as well as features. Several groups exhibited features from two or more than two creatures. Specimens of these in-betweeners have been detected in Zambia, Morocco, and Tanzania and all of them bear similarities with Maba 1. 

Another noteworthy finding that came to light through the examination was regarding the fossil's morphology. It was found to be very close in features to Homo Erectus. This is shocking, as the same amount of similarity is not found with later species like H. neanderthalensis and H. sapiens.

Researchers in regards to the fossil's Neanderthal association shared that the creature did not just exhibit unique Neanderthal features. This implies that the qualities of other species were also detected.  A recent phylogenetic study speculated a Denisovan descent. A CT Scan of the brain also ruled that out, as the individual's brain was much smaller than a Denisovan brain. Based on all these findings, researchers believe that as of now, the only category suitable for the individual is 'non-erectus.'