Scientists from the National Center for Human Research (CENIEH) and the University of Cologne (Germany) analyzed the climatic conditions that people faced in Western Europe during the Middle Pleistocene.
The Middle Pleistocene, 125,000–780,000 years ago, was marked by periodic fluctuations between today’s climate and cooler phases. In a new study, paleotemperature maps were used to estimate the temperatures humans had to withstand in Europe during several of these climatic phases. From these maps, temperatures were obtained for a total of 68 sites where human presence was recorded between 360,000 and 470,000 years ago.
Researchers assessed their potential adaptations to cold using a thermoregulation model that mimics the loss of heat in humans during sleep. The results of this study show that humans had to endure very low temperatures during this period and, surprisingly, not only during the glacial phases, but also during milder times, even in places like Ambrona or Atapuerca in the Iberian Peninsula.
“It is difficult for us to imagine that people were able to withstand such harsh conditions, given that evidence of the use of fire in Europe during this period is extremely rare. In fact, many researchers believe that they were unable to generate and habitually use fire. “
Jesus Rodriguez, National Center for Human Research (CENIEH)
To evaluate the effectiveness of other cold management strategies, the researchers used a mathematical model that simulated heat loss during sleep and applied it to one man and one woman from the Sima de los Huesos settlement in Atapuerca, Burgos. This allowed them to evaluate the insulating effects of fur, thick subcutaneous fat, and internal heat production from metabolism, and to account for heat loss due to wind exposure.
Exposure to cold, especially at night, is a serious problem for thermoregulation. There is a limit to the metabolic response caused by cold temperatures at night, but where physiological mechanisms are not met, human behavior can fill the gap. People could come to terms with very low night temperatures if they slept in furs, especially if they did it in a group in a place protected from the wind.