A strange 14,000-year-old fossil recovered over a decade ago in a cave in the Yunnan province of China has given up its secrets; DNA analysis revealed who left them and where their ancestors went.
Unraveling the Mysteries of a 14,000-Year-Old Fossil: Human or Not?
Parts of the skull and thigh bones were found in the southwestern province of Yunnan, China, in 1989. Researchers from the Chinese Academy of Sciences evaluated the human fossils' nuclear and mitochondrial sequences discovering that they belonged to a woman dubbed Mengzi Ren, closely related to the human population that was the first to set foot in the Americas, reports ScienceAlert.
Radiocarbon dating conducted in 2008 pinpointed the age of the human fossils. However, the bone features of the remains puzzled experts. The shape of the skull found was akin to Neanderthals. However, they appeared to have smaller brains than modern-day humans. In 12,000 BC, Homo sapiens were already on the Earth, and Neanderthals disappeared roughly 40,000 years ago; a great mystery for scientists.
Initially, researchers hypothesized that the fossils belonged to an archaic hybrid species of unknown human origins called Red Deer Cave People. However, when genetic materials were recovered from the skullcap, researchers found evidence that it was a woman with direct human ancestry.
Neanderthal and Denisovan ancestry levels in the human fossils' genome were similar to modern-day humans. Results of the analysis were published in the journal Current Biology, titled "A Late Pleistocene human genome from Southwest China."
Fossil Genome vs. Modern-Day Humans
Comparing ancient and current human genomes from across the globe, researchers noted that the specimen was more related to Native Americans of East Asia. These people migrated from East Asia via Siberia in the Bering Strait before reaching the Americas and becoming the first Americans in human history.
The recent discovery fills in the gap in the history of human migration, as another branch of human ancestry was the initial focus of the research. America's "first peoples" haven't had their geographical locations delimited. However, the study sheds more light on the puzzle.
Unfortunately, experts couldn't extract enough detail from the fossil to determine why it differed from modern humans. The cave's heat, humidity, and acid soil allowed researchers to rescue only 11.3% of the ancestral genome of the fossils, reports California18. The study was the first DNA sequencing conducted on human fossils from South China.
Likewise, the specimen showed great genetic diversity, suggesting it coexisted with many human ancestors in East Asia during the late Stone Age. It is possible that the southern region was a refuge during the harshest periods of the Last Ice Age.
The fossil anatomy recovered was described as very robust, with one theory suggesting that its anatomy was very plastic, which corresponded with the environment and lifestyle of individuals. Humans lost this robustness by embarking on agriculture.
East and Southeast Asia have been the source of the oldest rock arts and various human fossils like the hobbits from Flores, Indonesia, and the dragon man of Northern China.
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