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Human-like lifespan 100,000–200,000 years ago?

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Teeth from the upper jaw of a child (the Xujiayao child) of about 6 and a half, who died between 100,000-200,000 years ago were examined by X-ray:

But the ancient child’s overall dental growth and development falls within the range observed among kids today, paleoanthropologist Song Xing of the Chinese Academy of Sciences in Beijing and her colleagues report online January 16 in Science Advances. That humanlike rate of dental development suggests that the youngster belonged to an East Asian Homo population with a relatively long life span and an extended period of child care, the researchers speculate. Those characteristics are associated with present-day humans’ lengthy period of tooth growth.Bruce Bower, “An ancient child from East Asia grew teeth like a modern human” at Science News

Abstract: Several human dental traits typical of modern humans appear to be associated with the prolonged period of development that is a key human attribute. Understanding when, and in which early hominins, these dental traits first appeared is thus of strong interest. Using x-ray multiresolution synchrotron phase-contrast microtomography, we quantify dental growth and development in an archaic Homo juvenile from the Xujiayao site in northern China dating to 161,000–224,000 years or 104,000–125,000 years before present. Despite the archaic morphology of Xujiayao hominins, most aspects of dental development of this juvenile fall within modern human ranges (e.g., prolonged crown formation time and delayed first molar eruption). For its estimated age-at-death (6.5 years), its state of dental development is comparable to that of equivalently aged modern children. These findings suggest that several facets of modern human dental growth and development evolved in East Asia before the appearance of fully modern human morphology. (open access) Song Xing, Paul Tafforeau, Mackie O’Hara, Mario Modesto-Mata, Laura Martín-Francés, María Martinón-Torres, Limin Zhang, Lynne A. Schepartz, José María Bermúdez de Castro and Debbie Guatelli-Steinberg, First systematic assessment of dental growth and development in an archaic hominin (genus, Homo) from East Asia Science Advances 16 Jan 2019: Vol. 5, no. 1, eaau0930 DOI: 10.1126/sciadv.aau0930 More.

The more we know, the more our ancestors seem like ourselves.

See also: Researcher: Teeth are an astonishing source of information

Two Neanderthal Children From 250 Kya Showed Lead Exposure, And Much Else

Researcher: Ancient people were NOT all dead by 30 years of age This matter is worth clarifying because people arguing dubious claims about the mindset of ancient man sometimes assume that few people were around much beyond thirty years of age. But enough of them were around that the lifespan of 70 to 80 years was accepted as the norm for a human being, irrespective of the percentage of the population that reached it.

The maximum lifespan 2000 years ago was just above 100 years. The maximum lifespan today is just above 100 years. What has changed is an increase in median age at death. This has nothing to do with evolution. Ed George
Well, yes. Examination of skeletons of ancient Britons, who lived only a few thousand years ago, show an average for females of 18 and for males of 25. But of course infant mortality was undoubtedly around 50% (as it remains in countries without Western medical facilities and clean water). And this is from the coldest, rockiest, most godforsaken coasts of what is now northern Scotland. Further south and further inland, life was undoubtedly easier. vmahuna

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