A refined chronology of the Naumann’s elephant (Palaeoloxodon naumanni) provides a new insight on factors of their extinction
摘要
Cimatic shifts, human hunting pressure, or their combined effects have been considered the major drivers of the extinction of large mammals in the Late Pleistocene. Understanding the impact of human activity on extinction has long been a topic of interest because of its connection to human nature. Radiocarbon dating of fossils of Naumann’s elephant (Palaeoloxodon naumanni) in the Japanese Archipelago has suggested an extinction date of 24 k cal BP. However, contamination has not been adequately removed from the fossil samples, thereby necessitating the verification of radiocarbon dates. Here, we used an ultrafiltration method that purifies long-chained collagen and dated reported fossils and new collections salvaged from the Seto Inland Sea, western Japan. The radiocarbon dates of resampled specimens showed older ages than previous estimates. Our new estimation was 35–33 k cal BP. When compared with human demography, which rapidly increased after 39 k cal BP, this estimation showed a shorter coexistence interval of 6–4 k years and, furthermore, implied spatial independence between them. These findings might suggest that the extinction of Naumann’s elephant can be attributed mostly to climatic shifts, with a possible limited effect from humans.