A sudden cold snap, 1.1 million years ago, caused by changes in the Atlantic currents, could have made life impossible for archaic humans who had populated Western Europe, including what is now the British Isles. Their extinction cleared the way for later colonisation, first by Neanderthals about 250,000 years ago, followed by anatomically modern Homo sapiens, about 40,000 years ago.
Evidence of this extreme climate change and subsequent mass extinction was found by paleoclimate scientists from UCL, University of Cambridge and CSIC Barcelona who analysed the chemical composition of marine micro-organisms and examined the pollen content in a deep-sea sediment core recovered from off the coast of Portugal. This showed evidence of a sudden cooling with ocean surface temperatures falling to 6oC off Lisbon and semi-desertification of the surrounding area. Parts of the Mediterranean coast would have resembled the Asian steppe.
During the cold snap 1.1 million years ago, the Mediterranean might have looked similar to the Asian steppe.
Image © Panikhin Sergey/Shutterstock.
The oldest known human remains in Europe have previously been recovered from Iberia and suggest that early humans had arrived from southwest Asia by about 1.4 million years ago. The climate around that time would have generally been warm and wet, punctuated by mild cold periods. Up to now, the prevailing theory has been that once humans arrived, they were able to survive through multiple climate cycles and adapt to increasingly harsh conditions after 900,000 years ago.The research findings are also explained in a press release from the Natural History Museum, London, UK. This gives more background to the earlier colonisation of Western Europe, the mass extinction and subsequent re-population:
Paleoclimate scientists from UCL, University of Cambridge and CSIC Barcelona analysed the chemical composition of marine micro-organisms and examined the pollen content in a deep-sea sediment core recovered from off the coast of Portugal. This revealed the presence of abrupt climate changes that culminated in an extreme glacial cooling, with ocean surface temperatures off Lisbon dropping below 6°C and semi-deserts expanding on the adjacent land.Our discovery of an extreme glacial cooling event around 1.1 million years ago challenges the idea of continuous early human occupation of Europe.
Professor Polychronis C. Tzedakis, senior author.
Environmental Change Research Centre
Department of Geography
University College London, London, UK.
To our surprise, we found that this cooling at 1.1 million years ago was comparable to some of the most severe events of recent ice ages.
Dr Vasiliki Margari, Lead author
Environmental Change Research Centre
Department of Geography
University College London, London, UK.To assess the climate impact on early human populations, co-corresponding author Professor Axel Timmermann and his team from the IBS Center for Climate Physics at Pusan National University ran a climate simulation on their supercomputer Aleph to capture the extreme conditions during this time. Combining the output of the simulation with fossil and archaeological evidence of human occupation in southwest Eurasia, the team then developed a human habitat model, which predicts how suitable the environment was for early human occupation.A cooling of this magnitude would have placed small hunter-gatherer bands under considerable stress, especially since early humans may have lacked adaptations such as sufficient fat insulation and also the means to make fire, effective clothing or shelters.
Professor Nick M. Ashton, co-author
Department of Britain, Europe and Prehistory
British Museum, London, UK.
Together, the paleoclimate data and human habitat model results indicate that Iberia, and more generally southern Europe, was depopulated during the Early Pleistocene. An apparent lack of stone tools and human remains over the next 200,000 years further raises the possibility of a long-lasting hiatus in European occupation.The results showed that 1.1 million years ago climate around the Mediterranean became too hostile for archaic humans.
Professor Axel Timmermann, co-corresponding author.
Institute for Basic Science
Center for Climate Physics
Busan, South Korea.
According to this scenario, Europe may have been recolonized around 900,000 years ago by more resilient humans with evolutionary or behavioural changes that allowed survival in the increasing intensity of glacial conditions.
Professor Chris B. Stringer, co-author
Centre for Human Evolution Research
The Natural History Museum, London, UK.The research was led by scientists at UCL Geography and the IBS Center for Climate Physics, Pusan National University, South Korea in partnership with researchers from the Cambridge University, CSIC Barcelona, the Natural History Museum, London, the British Museum and the UCL Institute of Archaeology.
The earliest evidence of humans in Europe comes from Dmanisi in Georgia, where fossils and stone tools dating back around 1.8 million years were unearthed. These fossils are usually assigned to the species Homo erectus and are generally agreed to be the first evidence of humans outside Africa. While some ancient humans continued travelling deeper into Asia, others moved west into Europe. Stone tools and fossils of ancient humans are known from Italy and southern Europe from between 1.4-1.5 million years ago, while others have been found in Spain from about 1.2 million years ago.
[…]
At the time, the climate of the Mediterranean region was generally similar to the present, but with wetter conditions that supported a mix of woodland, shrubland and wetland that provided a range of different food sources for humans and other wildlife. These periods of warmer conditions alternated with periods of relatively mild cold stages.
Until recently, it was thought that these variable conditions continued until around 900,000 years ago, when changes to climate cycles meant that Europe’s cold periods became longer and more intense. But this new study has revealed that around 1.1 million years ago there was a much harsher cold snap which had potentially fatal consequences for the humans living in Europe at the time.
The researchers used the marine cores taken from the coast of Portugal to calculate the ocean temperature at the time by examining the levels of organic molecules produced by a type of marine plankton. They also looked at pollen levels to get an idea of how the ecosystems on land were changing too.
[…]Changes in the lightness of sediment cores reflect the climate cycles of the distant past, allowing researchers to compare the timings with fossils.
The team believe that this cooling was caused by the melting and rapid disintegration of a large ice sheet covering the Arctic, as well as parts of North America and Europe. The large amount of freshwater entering the ocean would have disrupted the Atlantic Meridional Overturning Circulation (AMOC), which brings warm water from the tropics into the north Atlantic, and weakened it by as much as 95%.
How did Europe change 1.1 million years ago?
As Europe became colder, the world our ancient relatives were used to would have changed dramatically.
The scientists estimated that the amount of habitable Mediterranean coastline for our ancestors would have halved, with overall plant growth dropping by a similar amount. Instead, semi-desert conditions similar to the steppes of Asia today would have become more prevalent.
The team found that pollen associated with steppe plants, such as grasses and shrubs, was about 45% more common in the sediment following the temperature change.
As these plants are not especially nutritious for humans, it would have been more difficult for them to find enough food to survive. They may also have lacked additional fat reserves meaning they were less adapted to cold conditions.
As a result, the humans who didn’t immediately die during the harsh conditions would likely have looked for more hospitable places to live outside of Europe. While the team’s research focused on Spain and Portugal, they team suspect that the inhospitable conditions might have extended further along the Mediterranean coast, and perhaps even reached southwestern Asia.
If this was the case, then Europe may have been empty of humans for around 200,000 years. When humans did return between 850,000 and 950,000 years ago, they were quite different from the people they replaced.
‘When humans came back to Europe, as evidenced by ancient footprints in Happisburgh in the UK and similar aged sites, they were tolerating colder winters than today,’ Chris says. ‘It suggests they may have adapted to become more resilient to the cold, or had developed new hunting techniques, for example, to help them survive.’ ‘It’s assumed that these humans were Homo antecessor, based on the timing, but without human fossils at Happisburgh we can’t be sure.’
For more on the Happisburgh footprints, see Britain's Oldest Humans
And all this took place a million years before Earth and humans were created, according to creationist mythology.And of course, with the evidence of an evolutionary history of humans from archaic hominins, the existence of a founder couple without ancestors becomes increasingly ludicrous. And with that idea gone, with it goes the notion of original sin, the need for forgiveness and redemption and the need for a redeemer, so the alleged blood sacrifice of a man-god by a superstitious middle eastern tribe, becomes meaningless too.
And that eliminates the need for a priesthood and the 'cure' they sell us for the 'illness' they declare we all suffer from, and which only they have the cure, for which we should reward them with status and power, and usually lots of money.
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