Study suggests some population shifts during early and late Holocene were due to climate changes

November 21, 2017 by Bob Yirka, report
Bronze bead necklace Stage: Holocene Bronze age 1800-1500 BC . Credit: Didier Descouens/Wikipedia/CC BY-SA 4.0

(—A team of researchers from University College London and the University of Plymouth, both in the U.K., has found evidence that suggests at least some of the population shifts that have occurred over the past several thousand years in Britain and Ireland were likely due to climate change rather than human activities. In their paper published in Proceedings of the National Academy of Sciences, the group describes analyzing data from thousands of prior research efforts to create charts of population swings during the early and late Holocene, and then comparing what they found to climate research data from the same time periods.

Prior research has shown that there have been several in Britain and Ireland over the past several thousand years—populations tended to rise to a peak and then drop, presumably because of overtaxing resources, disease or warfare. But in this new effort, the researchers suggest that climatic changes may have been responsible for at least some of the population changes. To come to this conclusion, the team looked at data from prior research efforts that were focused on studying artifacts.

Radiocarbon dating was typically used on samples of bone, charred or waterlogged wood, and seeds found at excavations sites. The group used the data to create charts showing population changes over time. But they also broke the region into four categories: Southeast England, Northwest England and Wales, Scotland and Ireland. By noting population changes between the regions, the group detected common patterns as well as patterns that were unique for each.

They suggest that when all of the regions experienced similar populations shifts, it was most likely due to an external factor, which, they further suggest, was likely climate change. They point out, as one example, that prior climate research indicates that there was a period of higher densities of salt in the Greenland Ice Sheet, which happened to coincide with one of the drops in population across Britain and Ireland. The researchers suggest that it was likely an increase in North Atlantic storms that led to the saltier ice, which in turn implied rainier weather across the . That would have made growing crops more difficult, leading to less available food—and a subsequent drop in .

Explore further: Could the Neolithic revolution offer evidence of best ways to adapt to climate change?

More information: Andrew Bevan et al. Holocene fluctuations in human population demonstrate repeated links to food production and climate, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1709190114

We consider the long-term relationship between human demography, food production, and Holocene climate via an archaeological radiocarbon date series of unprecedented sampling density and detail. There is striking consistency in the inferred human population dynamics across different regions of Britain and Ireland during the middle and later Holocene. Major cross-regional population downturns in population coincide with episodes of more abrupt change in North Atlantic climate and witness societal responses in food procurement as visible in directly dated plants and animals, often with moves toward hardier cereals, increased pastoralism, and/or gathered resources. For the Neolithic, this evidence questions existing models of wholly endogenous demographic boom–bust. For the wider Holocene, it demonstrates that climate-related disruptions have been quasi-periodic drivers of societal and subsistence change.

Related Stories

Mitochondrial DNA shows past climate change effects on gulls

January 18, 2017

To understand the present and future, we have to start with the past. A new study in The Auk: Ornithological Advances uses the mitochondrial DNA of Heermann's Gulls to draw conclusions about how their population has expanded ...

Recommended for you

Propping up glaciers to avoid cataclysmic sea level rise

September 20, 2018

As global warming outpaces efforts to tame it, scientists have proposed building massive underwater structures to prevent an Antarctic glacier the size of Britain from sliding into the sea and lifting the world's oceans by ...

NASA balloon mission captures electric blue clouds

September 20, 2018

On the cusp of our atmosphere live a thin group of seasonal electric blue clouds. Forming 50 miles above the poles in summer, these clouds are known as noctilucent clouds or polar mesospheric clouds—PMCs. A recent NASA ...

Study tracks Hurricane Harvey stormwater with GPS

September 20, 2018

Hurricane Harvey dumped more than 5 feet (1.5 meters) of water on southeast Texas in late August 2017, making it the wettest recorded hurricane in U.S. history. But after the storm passed, where did all that water go?


Adjust slider to filter visible comments by rank

Display comments: newest first

1.8 / 5 (5) Nov 21, 2017
If the only tool you have is a hammer, every problem looks like a nail.
1 / 5 (2) Nov 22, 2017
The climate changes, always and forever (in any event, until the sun swallows the planet).
5 / 5 (1) Nov 22, 2017
The climate changes, always and forever (in any event, until the sun swallows the planet).

Is this supposed to be profound or relevant to...anything?
1 / 5 (3) Nov 22, 2017
Is this supposed to be profound or relevant to...anything?

If human-induced climate change were real it wouldn't need a PR department.

The climate changes. "The polar bears will be fine." -- Freeman Dyson.
5 / 5 (1) Dec 10, 2017
This polar bear isn't 'fine'. https://news.nati...nge-spd/

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.