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We weathered the Ice Age while similar species disappeared. Specialists still struggle khổng lồ understand why.

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Since the origin of our species approximately 300,000 years ago, modern humans have spread throughout the whole world, armed with the ability lớn adapt lớn our surroundings.

Beyond the innate talent khổng lồ withstand a wide variety of climates, Homo sapiens are also able to lớn endure episodes of extreme climate change. In the Ice Age, starting approximately 115,000 years ago, humans survived wild swings in the weather that their hominin relatives were ultimately unable to lớn stand. How did these humans vị it? Anthropologists và archeologists currently lack a clear-cut answer. Yet the murky theories and potential explanations often emphasize our species’ exceptional social abilities & knack for altering our surroundings to lớn our advantage.

A Climate Crisis

To understand how humans survived & adapted khổng lồ the Ice Age, it’s important to appreciate what they were dealing with. In long-lasting periods called ice ages, the temperatures throughout the planet’s atmosphere & surface cool, causing continental ice & glaciers lớn cover substantial swaths of the terrain. Though these periods are typically perceived as a constant freeze, ice ages actually feature frequent fluctuations in climate, as the temperatures oscillate between cold và colder. In fact, the period approximately 115,000 to 11,700 years ago, colloquially called the “Ice Age,” included incredible climate instability.

“The last 100,000 years plus has been a time of tremendous oscillation of both coldand warm in the higher latitudes, & also wet và dry in the lower latitudes,” says Rick Potts, the paleoanthropologist heading the Smithsonian Institution’s Human Origins Program. “This dynamism of the planet creates, for all organisms, a fundamental question of how survive the change.” Indeed, climate conditions caused serious consequences for many plant và animal species, which struggled lớn adapt to the abrupt shifts in their surroundings. Hominins certainly faced the same challenge.

The Other Hominins

At the beginning of the Ice Age, we weren’t the only hominin around. The last vestiges of the long-lived Homo erectus và short-statured Homo floresiensis traversed the islands of Indonesia. The Denisovans populated Asia. Và the Neanderthals toleratedthe cold conditions of Europe. Though these species, our closest evolutionary kin, had thrived in the past, they all vanished from the archeological record in the midst of the Ice Age. Why?

"There's almost certainly no universal explanation,” Potts says, “but there are plenty of ideas out there.”

One persistent theory proposes that these hominin species were wiped away when a smarter hominin species — our own — appeared in their territories and overcame themthrough violence or the takeover of food. “The dispersal of Homo sapiens,” Potts says, “around the time of the extinction of all of these different species raises suspicions, & those suspicions are amplified when people think about the violence that people have caused one another, even in our own species in historical times. So, people are always going to lớn suspect that our species killed off the others, but there's very little evidence to lớn indicate that.”

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Today, a vị trí cao nhất theory posits that the period’s abrupt climate changes contributed khổng lồ these populations’ disappearance. Recent research indicates that several sudden cold & arid stretches around 44,000 to lớn 40,000 years ago devastated the Neanderthals, despite their abundant biological & behavioral adaptations khổng lồ the cold. “The climate connection is pretty clear,” says John Shea, a paleoanthropologist at Stony Brook University. “Eventually,it gets too cold khổng lồ find food, và they froze khổng lồ death.” Some scholars, including Shea, speculate that the fluctuations in climate & food supply were worsened by demographics. Other studies indicate that the Neanderthals maintained such small và tenuous populations that any threats lớn their ability lớn reproduce — whether connected khổng lồ the climate or another cause — became almost impossible lớn surmount.

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The exact sizes of these hominin populations still evade specialists, and according lớn Shea, “estimates range by multiple orders of magnitude.” That said, paleoanthropologists increasingly look khổng lồ demographics to explain these Ice Age extinctions, though they’re quick to lớn temper their theories. “Extinctions,” Shea says, “can occur for many reasons,”and species don’t always disappear even when their populations stay small. Our own species remained relatively scattered throughout the period and persisted nonetheless, suggesting that other considerations are also at play.

A Sole Survivors

Almost all hominins disappeared during the Ice Age. Only a single species survived. But H. Sapiens had appeared many millennia prior to the Ice Age, approximately 200,000 years before, in the continent of Africa. In many ways, this was an auspicious location. When the Ice Age really rolled around about 200 millennia into our evolution, Potts says that this terrain remained isolated from the full force of glacial activity that other hominins experienced elsewhere.

That said, approximately 70,000 to 60,000 years ago, in the midst of the Ice Age, our species started khổng lồ spread throughout the planet for a variety of potential reasons. We moved into flourishing forests và arid, dry deserts. “They didn't have a map,” Potts says. “They were just going over to lớn the next valley và hillside khổng lồ see what was there, & some of them went quite a distance.” Eventually, these travelers entered the iciest glacial environments in Europe, landscapes that the cold-adapted Neanderthals attempted khổng lồ avoid.

Ultimately, our ancestors occupied an assortment of environments và endured the fickle cycles of climate change that occurred in each. Yet, the fact that they achieved this feat as other hominins faded from the archeological record is curious, considering their cultural similarities.

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“Hominins mô tả a mix of ancestral survival skills,” Shea says. They spent their time in complex social communities. They also communicated amongst themselves, imagined innovative solutions khổng lồ their problems, và invented và implemented specialized tools. “It’s not that we had something these extinct hominins lacked,” Shea says. “It’s that we used those skills differently.”

Speaking & Symbolism

The clearest example of early humans' ability to survive, says Shea, “is that they were doing something different in terms of signaling & transmitting information to lớn one another.” Though specialists have historically speculated that our own species is the only one capable of conversing, it's almost certain that the hominins were all able lớn communicate in one way or another. Some specialists even speculate that the hominins as early as H. Erectus possessed protolinguistic abilities. Beyond that, studies suggest that the Neanderthals possessed “auditory and speech capabilities” comparable to our own.

That said, our ability lớn communicate seems to lớn surpass that of our closest cousins considerably. Early H. Sapiens may have had amplified vocal flexibility thanks khổng lồ their anatomy, enabling their language to lớn proliferate & convey complex information about local surroundings, including flora và fauna and changing climate conditions. “The balance of evidence is pointing in favor of Homo sapiens having more effective control over the complexity of sounds,” Potts says. “Finer control … leads lớn cultural diversity and behavioral diversity, and, therefore, the ability to figure different things out in different places.”

Additionally, specialists say that H. Sapiens, more than any other animal, shared a sense of social identity that they communicated through symbolic activities, including rituals, personal adornment và art. This cultural camaraderie & symbolism, according khổng lồ Potts, helped our kin band together and build broad social connections beyond their communities. These connections functioned as a contingency plan in times of trouble. If climate change or any other issue caused a population in one area khổng lồ struggle, those people could turn lớn their neighbors. “If things were bad where you are,” Potts says, “you had allies elsewhere that could help you survive.”

Specialists bao tay that the other hominins, particularly the Neanderthals, also acquired social identities. The archeological record increasingly indicates that these individuals created simple symbolic artifacts, though they were not as adept at constructing supportive social ties. “The Neanderthals,” Potts says, “were really, really good at surviving in their local environments, but if things weren't good where they were at anygiven time, they didn't seem to lớn have the kind of long-distance social alliances that allowed Homo sapiens khổng lồ overcome all obstacles.”

Tool Technology

Another skill that helped humans survive through the Ice Age might be our ability to alter our surroundings, particularly in conceiving and creating sophisticated stone tools. Once again, H. Sapiens were far from the only species khổng lồ fashion sharp points and flakes. Thatsaid, they made substantial innovations in toolmaking by intentionally planning và spreading their technology, a process potentially connected to lớn communication abilities. “When you look at Homo sapiens,” Potts says, “the diversity of stone tools and the innovation of stone tools goes far beyond, as a totality, what the Neanderthals ever produced.”

Though there’s no academic consensus, toolmaking potentially played an important part in our species’ adaptability. “Our survival tool is basically our ability khổng lồ modify things. You go back khổng lồ the oldest stone tool,” Potts says, “and it's a modification of the environment. You pick up a stone & you modify it, and all of a sudden, you have sharp edges và you have pounding implements.” That, Potts adds, shapes the foundation of our species’ longevity. “Technology can help with solutions — solutions to where khổng lồ find food, when to lớn find food,how to lớn solve problems of survival.”

Overall, changing climate conditions provided our species an opportunity lớn perfect our biggest & best skills — our communication và willingness khổng lồ make our mark on the world. & when we emerged from the frost, our species only improved upon those talents. When the world thawed about 11,700 years ago, humans began banding together to cultivate crops và create settlements for the first time, forming the foundations for the first civilizations.

“Civilization arose,” Shea says, “because we lived in a stable climate that permitted agriculture, that permitted people stay in one place.”