Most humans haven’t evolved to handle the cold, yet we dominate northern climates – and here’s why

Many people fear the cold of winter. Credit: Maria Boyko/Shutterstock

Humans are a tropical species. We’ve lived in warm climates for most of our evolutionary history, which may explain why so many of us spend winter huddled under a blanket, holding a hot water bottle and dreaming of summer.

In fact, all living monkeys are found in the tropics. The oldest known fossils come from the human lineage (hominin) from the middle And East of Africa. The hominins who spread north to higher latitudes had to contend, for the first time, with freezing temperatures, shorter days that limited foraging time, and snow that Make hunting more difficult And the icy wind cools it Exacerbation of heat loss from their bodies.

Given our limited adaptation to cold, why did our species come to dominate not only our ancestral warm lands but every part of the globe? The answer lies in our ability to develop complex cultural solutions to life’s challenges.

The oldest signs of hominins living in Northern Europe are from Habisburgh in Norfolkeastern England, where 900,000-year-old footprints and Stone tools Have been found. At the time, it was dominated by Habsburg Coniferous forests with cold winters, similar to southern Scandinavia today. There is little evidence that the Habsburg hominins remained at the site for long, suggesting that they did not have time to adapt physically.

It is still a bit of a mystery how these hominins survived the difficult conditions that were so different from their African ancestral homelands. There are no caves in the area and no evidence of shelters. The Habsburg artifacts are simple, indicating no complex technology.

Evidence intentional fire At this time controversial. tools for Sewing fitted and weather-resistant clothing It does not appear in Western Europe until about 850,000 years later. Many animals migrate to avoid the seasonal cold, however Habisburg hominins He would have had to travel 800 km south to make a tangible difference.

It is hard to imagine hominins surviving the ancient winters of Norfolk without fire or warm clothing. However, the fact that hominins were up north I mean, they found a way to survive the cold, so who knows what archaeologists will find in the future.

Boxgrove Hunters

Sites from modern settlements, such as Boxgrove in West Sussex, southern England, provide more clues about how ancient hominins survived northern climates. the Boxgrove website It dates back nearly 500,000 years, when the climate spiraled towards one of the coldest periods in history. human history.

There is good evidence for this Hominins hunted animals, from the cut marks on the bones, to the horse’s shoulder blade possibly pierced with a wooden spear. These findings fit with studies of people living as foragers today that show people in cold regions dependent on animal prey more than their warm climate counterparts. Meat is rich in calories and fat, which is needed to beat a cold.

fossil Hominids Boxgrove’s tibia is robust compared to living humans, indicating that it belonged to A A tall, stocky humanoid. larger bodies With Its limbs are relatively short decrease heat loss by underestimating surface area.

The best silhouette to avoid heat loss is the ball, even animals and humans cold climates Get as close to this shape as possible. There is also The clearest guide campfires during this period.

Cold Climate Specialists

Neanderthals, who lived in Eurasia about 400,000-40,000 years ago, It inhabits an icy climate . Compared to their ancestors in Africa, and for us, they had Its limbs are short and strongLarge, muscular bodies suitable for heat production and retention.

However, the prominent Neanderthal face and beaked nose are the exact opposite of what we might expect for an Ice Age adaptation. Likes Japanese macaques living in cold regions Mice raised in cool conditions, Humans live from cold climates They tend to have relatively high, narrow noses and broad, flat cheekbones.

computer modeling Many ancient skeletons indicate that Neanderthal noses were more efficient than those of earlier warmth-adapted species at conserving heat and moisture. The internal structure appears to be as important as the overall nose size.

Even with a physique adapted to coldness, Neanderthals were still hostage to their tropical ancestors. For example, they were lacking thick fur Other mammals of glacial Europe include the woolly rhinoceros and musk oxen. Instead, Neanderthals evolved a complex culture of coping.

there Archaeological evidence They made clothes and shelters from animal skins. Evidence to cook And the use of fire in its manufacture Birch wood glue For the manufacture of tools, the Neanderthals developed control over fire.

Most controversial, some archaeologists say Early Neanderthal bones from the 400,000-year-old site of Sima de los Huesos in northern Spain show seasonal damage from slowing metabolisms into hibernation. The authors argue that these bones show intermittent cycles of growth and healing.

Only a few species of primates hibernate such as some of Madagascar’s lemurs Small African shrubBeside Dwarf slow loris in northern Vietnam.

This might give you an idea that humans can also hibernate. But most species hibernate small bodies, with some exceptions such as bears. Humans may be too old to hibernate.

Jack of all trades

The oldest fossils of Homo sapiens date back to 300,000 years ago. from Morocco. But we did not spread out of Africa until about 60,000 years agocolony all over the world. This makes us relative newcomers to most of the habitats we inhabit now. Over the intervening millennia, people living in freezing cold places have biologically adapted to their environment but on a small scale.

One well-known example of this adaptation is that in regions with low sunlight, Homo sapiens I developed lighter skin tones, which is considered the best in the manufacture of vitamin D. Genomes of living Inuit populations from Greenland show physiological adaptation to The high-fat marine dietUseful in the cold.

More direct DNA evidence comes from a single 4,000-year-old hair preserved in permafrost from Greenland. Poetry alludes to Genetic changes This resulted in a stocky body shape that increased heat production and retention. Like hominins, we have only one shin bone from the Boxgrove site.

Our tropical heritage means we still can’t live in cold places without developing ways to deal with the temperatures. Take, for example, traditional Inuit parkawhich provides better insulation than modern Canadian Army winter uniforms.

This was the human capacity for behavioral adaptation crucial to our evolutionary success. until compared to other primatesHumans show less physical climatic adaptation. Behavioral adaptation is faster and more flexible than biological adaptation. Humans are Ultimate TransformersThey thrive in almost every possible ecological niche.

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