Directdating

Posted by / 15-Nov-2017 04:30

Directdating

In the absence of these, we propose that their extinction was possibly the result of long-term demographic and genetic declines associated with an isolated island population.Stegodons (Stegodontidae: Proboscidea) were a widespread and diverse family of proboscideans dating from the late Miocene to the Late Pleistocene of Africa and Asia.Here we report on uranium-series dating of a stegodon tusk recovered from the Ainaro Gravels of Timor.The six dates obtained indicate the local presence of stegodons in Timor at or before 130 ka, significantly pre-dating the earliest evidence of humans on the island.Pleistocene species of stegodon were widely dispersed throughout continental and island Southeast Asia (Louys, Curnoe & Tong, 2007), but became globally extinct by the terminal Pleistocene on both the mainland (Turvey et al., 2013) and on islands (Van den Bergh et al., 2008).Ultimate causes for their global extinction are likely multi-faceted, although it’s been proposed that continental and insular forms were adversely affected by environmental changes associated with glacial-interglacial cycles and volcanic eruptions, respectively (Louys, Curnoe & Tong, 2007; Louys, 2008; Van den Bergh et al., 2008).

) Have you ever wondered what makes this kind of huge difference in men’s lives?We present the first set of radiocarbon dates derived from human skeletal material from Ganj Dareh, Iran.These new dates fully overlap with those on goat bone samples published by Zeder and Hesse (2000) and confirm the finding of the latter source that occupation of the site occurred within 200–300 years after 9000 bp (~ 10,100 cal. In so doing we confirm the absence of a hiatus between the lower two levels (E and D), an idea derived from the initial dating of the site.We also provide the first full review of the 23 radiocarbon dates from the site published prior to the work of Zeder and Hesse (2000).Examination of the full date sequence emphasizes the complexity of the site stratigraphy and tight clustering of the dates from all levels, thereby clarifying the difficulty that the excavator had in separating levels.

directdating-37directdating-19directdating-19

Genetic and geographic isolation of stegodon populations resulted in dwarfing, speciation, and extinctions, with these processes playing out on different islands at different times (Van den Bergh, 1999; Van der Geer et al., 2010).

One thought on “directdating”

  1. But as lots of men and women like Stephen and Marietta have discovered, just because a relationship is physically challenging, it doesn’t have to be your cue to run for the exits. The heart works just fine, even if some body parts don’t.