Του Γιώργου Λεκάκη
Μια διεθνής ομάδα ερευνητών,
συμπεριλαμβανομένων επιστημόνων από το Πανεπιστήμιο Nanjing, το Πανεπιστήμιο
Fudan, το Ινστιτούτο Ερευνών του Μουσείου της Αυστραλίας και το Εθνικό Πανεπιστήμιο
της Ταϊβάν, ανέλυσε ανθρώπινα δόντια, που ανακτήθηκαν από πέντε σπηλιές της
νότιας Κίνας και τα βρήκε να είναι περίπου 16.000 χρόνων[1].
Αυτή η χρονολόγηση ελήφθη
μέσω του άνθρακα-14, των δοντιών και του άνθρακα που βρέθηκαν κοντά τους.
Το μιτοχονδριακό DNA που αποκτήθηκε από τα δόντια, επιβεβαίωσε ότι ανήκαν σε σύγχρονους ανθρώπους (homo sapiens) και σχετίζονται με ανθρώπους που ζουν σήμερα στο Θιβέτ και την Βιρμανία.
ΠΗΓΗ: Xue-feng Sun et al. «Ancient DNA and multimethod dating confirm the late arrival of anatomically modernhumans in southern China», στο Proceedings of the National Academy of Sciences (2021), DOI: 10.1073/pnas.2019158118. Και στο Science X Network. ΑΡΧΕΙΟΝ ΠΟΛΙΤΙΣΜΟΥ, 9.2.2021.
ΠΕΡΙΣΣΟΤΕΡΑ για την ΑΠΩ ΑΝΑΤΟΛΗ, ΕΔΩ.
Significance
Genetic studies show the founders of all living non-African populations expanded from Africa ca. 65 to 45 ka. This “late dispersal” model has been challenged by the discovery of isolated AMHs at caves in southern China suggested as early as ca. 120 ka. We assessed the age of early AMH fossils from five caves in this region using ancient DNA analysis and a multimethod geological dating strategy. We found they were much younger than previously suggested, with some remains dating to the Holocene owing to the complex depositional history at these subtropical caves. Current evidence shows AMHs settled southern China within the timeframe set by molecular data of less than ca. 50 to 45 ka and no earlier.
Abstract
The expansion of anatomically modern humans (AMHs) from Africa around
65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of
present-day non-African populations. Some paleoanthropologists have argued that
fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern
China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We
investigated the age of the human remains from three of these localities and
two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining
ancient DNA (aDNA) analysis with a multimethod geological dating strategy.
Although U–Th dating of capping flowstones suggested they lie within the range
ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth
from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating
of sediments and AMS 14C analysis of mammal teeth and charcoal also
demonstrated major discrepancies from the flowstone ages; the difference
between them being an order of magnitude or more at most of these localities. Our
work highlights the surprisingly complex depositional history recorded at these
subtropical caves which involved one or more episodes of erosion and
redeposition or intrusion as recently as the late Holocene. In light of our
findings, the first appearance datum for AMHs in southern China should probably
lie within the timeframe set by molecular data of ca. 50 to 45 ka.
[1] Προηγούμενη έρευνα, η οποία επικεντρώθηκε στην χρονολόγηση ιζημάτων κοντά στα δόντια, και όχι στα ίδια τα δόντια, έδειξε ότι ήταν 120.000 χρόνων!
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