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From about 32 kya to 22 kya, prevailed in Europe. That culture produced the and art such as the . By 20 kya, . But as far as human expansion is concerned, the Gravettian (and related cultures) are most notorious as mammoth hunters extraordinaire for those that lived on the near the ice sheets. To , they could not swim to Sahul, but flourished everywhere else they could get to. At , they were the ultimate hunter-gatherer kill. Also, near the ice sheets, meat could be stored in the ground. Cro-Magnons did just that, and that “freezer” full of meat led to the first seasonally sedentary humans. It long predated the Domestication Revolution when people could be sedentary year-round, but while the megafauna lasted, the first signs of what came later appeared as Cro-Magnons created villages around frozen mammoth meat. Gravettians hunted along migration routes and set traps and ambushes for mammoths. For thousands of years, mammoths were the primary focus of Gravettian hunters, and many scientists believe that humans at least . Gravettians probably used the bow and arrow, and using poisoned arrows on mammoths would have been child’s play, not a hazardous undertaking. They also tended to focus on the easy meat: the young, relatively defenseless, tender mammoths. Killing the offspring alone would have driven the slowly reproducing mammoths to extinction, and as the interglacial period began around 15 kya, there would have been new pressures on mammoths. One of them was that fewer mammoths meant that they were not terraforming their environments like they used to, and the warming climate probably reduced their range. For a mammoth facing humans, there was literally no place to hide (except maybe in the living room), and there is little reason to think that hunters would have eased up when mammoth numbers dwindled. If anything, their efforts would have to get the last ones, as they competed and fought over the final mammoths. In one lifetime or even several, the changes would have been barely noticeable, if at all. There was simply no way out for mammoths, and they went extinct south of the European ice sheets under the ministrations of Cro-Magnon hunters. More evidence of their fate is some mammoths surviving in refugia: islands where humans did not arrive until thousands of years later. mammoths survived on in the chain off of Alaska until less than six kya, and went extinct when humans arrived. Several hundred apparently full-sized mammoths survived on near Siberia and went extinct less than five kya, when humans arrived. In today's France and Spain, Gravettians also semi-settled along the migration routes of reindeer and red deer. From Spain across Europe, into today's Russia, Gravettians hunted migrating herds, and not only the mammoth was driven to extinction, but also the wooly rhino, the Irish elk, the musk ox, and steppe bison were driven to extinction as the ice sheets retreated. Neanderthals had been ambush hunting in similar fashion, and those animals, like the African megafauna, grew wary of humans, and killing those animals probably took planning and guile.
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What human-agency skeptics have ignored or argued around are unique features of the megafauna that went extinct the humans that preyed on them, while they examined minutia. ever before humans arrived. As , African elephants help create the biomes they live in, as terraforming agents. They were far from idle browsers and grazers, but had outsized impacts on the vegetation, soils, and geological features such as water holes. Dinosaurs may have had similar biome impacts, and it was probably a feature of that large herbivore guild. Scientists have been finding plenty of evidence that vegetation changes that human-agency skeptics attribute to climate change may well be largely the of the guild’s disappearance, not a cause. Researchers in Africa have also discovered that changes wrought by elephants created biomes dependent on elephant management. When elephants disappeared, so did the biomes that they created, which is why smaller species could also disappear when the large herbivore guild vanished. Although Australia was the only non-Antarctic continent without proboscideans 50 kya, and its guilds were comprised of somewhat smaller animals, probably reflecting inherent differences between placental and marsupial mammals, Australia's large herbivores probably had similar biome impacts.
Plants are as intricate and complicated as animals
As impressive as the capabilities and survival history of the global megafauna were, what seems far more difficult to explain away are the humans that arrived when the global megafauna went suddenly extinct. The only megafauna of note to survive were those that had lived with humans in Africa and Eurasia for more than a million years and learned to avoid them, as almost all game animals do today.