That’s what this study suggests. But I wonder, did those volcanoes erupt in sync with the Laschamps magnetic reversal? Because if they did, then the magnetic reversal was actually the real culprit.
“Volcanoes Killed Off Neanderthals, Study Suggests”
Thus reads the title in the National Geographic News.
Catastrophic volcanic eruptions in Europe may have culled Neanderthals to the point where they couldn’t bounce back, according to this article.
However, modern humans apparently escaped extinction due to their far-flung fallback populations in Africa and Asia.
About 40,000 years ago in what we now call Italy and the Caucasus Mountains, which straddle Europe and Asia, several volcanoes erupted in quick succession, according to a study published in the October 2010 issue of the journal Current Anthropology.
It’s likely the eruptions reduced or wiped out local bands of Neanderthals and indirectly affected farther-flung populations, the team concluded after analyzing pollen and ash from the affected area. (See volcano pictures.)
The more volcanic ash a layer had, the less plant pollen it contained
The researchers examined sediments layer from around 40,000 years ago in Russia’s Mezmaiskaya Cave and found that the more volcanic ash a layer had, the less plant pollen it contained.
“We tested all the layers for this volcanic ash signature. The most volcanic-ash-rich layer”—likely corresponding to the so-called Campanian Ignimbrite eruption, which occurred near Naples (map)—”had no [tree] pollen and very little pollen from other types of plants,” said study team member Naomi Cleghorn, an anthropologist at the University of Texas, Arlington. “It’s just a sterile layer.”
The loss of plants would have led to a decline in plant-eating mammals, which in turn would have affected the Neanderthals, who hunted large mammals for food.
If the volcanoes theory is correct, the Neanderthals died slowly in a cold and desolate landscape bereft of food sources. A tragic ending.
The most powerful eruption in Europe in the last 200,000 years
The eruptions 40,000 years ago were unlike anything Neanderthals had faced before, Cleghorn and company say.
For one thing, all the volcanoes apparently erupted around the same time. And one of those blasts, the Campanian Ignimbrite, is thought to have been the most powerful eruption in Europe in the last 200,000 years.
“It’s much easier to adapt to something that’s happening over a couple of generations,” Cleghorn said. “You can move around, you can find other places to live, and your population can rebound.
“This is not that kind of event,” she said. With their small population groups, ‘(the) Neanderthals didn’t really have the numbers and the density” to rebuild their populations after the eruptions.
Only after the Neanderthals were gone did Homo sapiens populations explode, says Cleghorn. “We think Neanderthals were still holding their own and might have held out for much longer, if it hadn’t been for the devastating impact of these eruptions.”
Did those volcanoes erupt in sync with the Laschamps magnetic reversal?
I think the answer has to be yes.
The above article points to the huge series of volcanic eruptions known as the Campanian Ignimbrite as the culprit.
When you look that up on Wikipedia, you find that the Campanian Ignimbrite eruption was a major volcanic eruption in the Mediterranean during the late Quaternary. That eruption has been attributed to the Archiflegreo volcano, the 13-km-wide (8.1 mi) caldera of the Phlegraean Fields, located 20 km (12 mi) west of Mount Vesuvius under the western outskirts of the city of Naples and the Gulf of Pozzuoli, Italy.
Estimates of the date and magnitude of the eruption(s) vary considerably.
There are three named Phlegraean Periods. The First Period, which includes the Campanian Ignimbrite Eruption was the most decisive era in the Phlegraean Fields’ geologic history. Beginning more than 40,000 years ago (emphasis added) as the external caldera formed, subsequent caldera collapses and repeated volcanic activity took place within a limited area.
If that date estimate is correct – “beginning more than 40,000 years ago” – I think it would place those eruptions almost directly at the Laschamp Magnetic Reversal.
Especially when you consider this article that I posted just a few days ago: “Did magnetic excursion cause Neanderthal extinction?”
In that article, I pointed out that the Laschamps excursion occurred 41,400 (±2,000) years ago, and that it was first recognised from a geomagnetic excursion discovered c. 1969 in the Laschamps lava flows in the Clermont-Ferrand district of France.
Magnetic field remained reversed for approx 440 years
The earth’s magnetic field remained reversed for approximately 440 years, with the transition from the normal field lasting approximately 250 years. The reversed field was 75% weaker whereas the strength dropped to only 5% of the current strength during the transition. This reduction in geomagnetic field strength resulted in more cosmic rays reaching the Earth, causing greater production of the cosmogenic isotopes beryllium 10 and carbon 14.
Knowing all of the above, I maintain that the Laschamp magnetic reversal triggered the Campanian Ignimbrite Eruption. The ensuing famine, along with the radioactive materials raining onto our planet (because magnetic field strengh was 75% weaker) and an abrupt descent into an ice age, wiped out the Neanderthals.
At the same time, the magnetic reversal would have triggered massive underwater volcanic activity, thereby heating the oceans and leading to more and more moisture rising into the skies already cooled by the above-water volcanic activity. And there you have it; ever bigger snowstorms and a descent into an ice age.
This is why I am concerned about our declining magnetic-field strength, because it could be the precursor to another magnetic reversal.
See all of the National Geographic article, published 22 Sep 2010:
See the Wikipedia article on the Campanian Ignimbrite eruption
See Wikipedia article on the Lashamp event: