john hawks weblog

paleoanthropology, genetics and evolution

Where there's not smoke...

Sun, 2010-02-14 23:15 -- John Hawks

Anne-Laure Daniau, Francesco d'Errico and Maria Fernanda Sánchez Goñi went looking for signs that Upper Paleolithic Europeans were using fire to control ecosystems, similar to what is believed to have happened in Southeast Asia, Australia, and the New World under human agency during the terminal Pleistocene.

They didn't find any.

Our results show that contrary to Southeast Asia, no major increase in fire regime is recorded in Southwestern Iberia or in Western France at the onset or after the colonisation of these regions by Modern Human populations. CCsurf values associated in Southeast Asia with Modern Human impact are twice as great as the highest figures recorded in the same sequences for the period before colonisation by Modern Humans. Such a dramatic increase is not observed in our records. Also, no shift is observed in the vegetation apart from that expected by the impact of the millennial scale climatic variability on plant communities, and no increase in taxa that might be related to an increase in fire. Although the Southeast Asian and the European trends are difficult to compare considering the different latitudinal, paleoclimatic and vegetation settings, the coincidence in the former area between the peopling event and the increase in biomass burning makes it conceivable that the two phenomena are related in some way.

Our results strongly argue against the view that Neanderthals and Modern Humans were the driving factor of the large scale variations in fire regime observed in our records, which were clearly governed by the D-O millennial-scale climatic variability and its impact on fuel load. However, we cannot rule out at this stage the possibility that either one or both populations used fire for ecosystem management in ways that did not significantly affect the natural fire trend.

This is a great study. They sure looked hard, sampling microcharcoal particles from a deep sea core covering the span from 70,000 to 10,000 years ago. It's a nice record of fire on the European continent, and shows fluctuations on a millennial timescale. No sign of any other influence -- in particular, no sign that the Upper Paleolithic made any difference at all.

Negative results are in some ways more interesting than positive ones. In this case, it's not so unexpected that the humans didn't burn systematically -- Europe just ain't so easy to burn. Getting some confidence about that gives another kind of climate record. Plus it tells us one thing that didn't hurt the Neandertals.

References:

Daniau A-L, d'Errico F, Sánchez Goñi MF (2010) Testing the Hypothesis of Fire Use for Ecosystem Management by Neanderthal and Upper Palaeolithic Modern Human Populations. PLoS ONE 5(2): e9157. doi:10.1371/journal.pone.0009157

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