Neanderthal - Extinction Hypotheses

Extinction Hypotheses

Neanderthal fossils found in Vindija Cave in Croatia have been dated to between 32,000 and 33,000 years old, and what have been claimed as the last traces of Mousterian culture (Neanderthal artefacts but not bones) have been found in Gorham's Cave on the remote south-facing coast of Gibraltar, dated to less than 30,000 years ago. However, a recent re-examination of Neanderthal bones from two Spanish Neanderthal sites has suggested they were around 45,000 years old, 10,000 years older than previously thought. Clive Finlayson, who excavated Gorham's Cave, argues that the sites which have been re-dated are highland ones which would have been inhospitable in the approach to an ice age. However bone collagen degrades in the warmer lowland sites where Finlayson thinks Neanderthals would have survived longer, and it has yet to be determined whether the re-dating affects other Neanderthal sites with reported recent dates.

Possible scenarios for the extinction of the Neanderthals are:

1. Neanderthals were a separate species from modern humans, and became extinct (because of climate change or interaction with humans) and were replaced by modern humans moving into their habitat beginning around 80,000 years ago. Competition with humans probably contributed to Neanderthal extinction. Jared Diamond has suggested a scenario of violent conflict and displacement.
2. Neanderthals were a contemporary subspecies that bred with modern humans and disappeared through absorption (interbreeding theory).
3. A Campanian ignimbrite volcanic super-eruption around 40,000 years ago, followed by a second one a few thousand years later, has been hypothesised as having contributed to the demise of the Neanderthal, based on evidence from Mezmaiskaya cave in the Caucasus Mountains of southern Russia Mitochondrial DNA (mtDNA) analysis of a specimen from Mezmaiskaya Cave is radiocarbon dated to be about 29,000 years BP and therefore from one of the latest living Neanderthal individuals. The sequence shows 3.48% divergence from the Feldhofer Neanderthal. Phylogenetic analysis places the two Neanderthals from the Caucasus and western Germany together in a clade that is distinct from modern humans, suggesting that their mtDNA types have not contributed to the modern human mtDNA pool.

As Paul Jordan notes: "A natural sympathy for the underdog and the disadvantaged lends a sad poignancy to the fate of the Neanderthal folk, however it came about." Jordan, though, does say that there was perhaps interbreeding to some extent, but that populations that remained totally Neanderthal were probably out-competed and marginalized to extinction by the Aurignacians.