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📖 Texto de lectura

The extinction of the woolly mammoth has long been attributed to human overhunting, but recent evidence suggests that climate change was the primary driver. First, the timing of their decline correlates with the end of the last Ice Age, when global temperatures rose rapidly. As the climate warmed, the steppe-tundra habitat that mammoths depended on shrank dramatically, replaced by forests and wetlands. This habitat loss would have reduced food availability, making populations vulnerable. Second, while humans did hunt mammoths, archaeological evidence shows that hunting pressure was relatively low. For example, at sites where mammoth bones are abundant, many show signs of natural death rather than butchery, and stone tools associated with mammoth hunting are rare. Third, mammoths survived on isolated islands, such as Wrangel Island, long after the mainland populations vanished. On Wrangel Island, humans did not arrive until about 4,000 years ago, yet the mammoths persisted until around 3,700 years ago—a short overlap that suggests climate, not humans, caused their eventual demise, possibly due to a final environmental shift.

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The reading’s argument that climate change alone drove mammoth extinction is not convincing. First, the correlation with the Ice Age’s end does not prove causation. In fact, during earlier interglacial periods, mammoths thrived in warmer conditions, indicating they could adapt to climate shifts. The real problem was not warmth itself but the arrival of human hunters, who may have exacerbated stress on already fragmented populations. Second, the claim that hunting was minimal is misleading. Many mammoth bone sites lack butchery marks because humans used bones for fuel or building, not just food. Also, stone tools may be rare because hunters used organic materials like wood or bone, which decay. Recent isotope analyses of mammoth tusks show that some individuals were killed during times of nutritional stress, consistent with selective hunting. Third, the Wrangel Island case actually supports the human role. When humans arrived around 4,000 years ago, the mammoth population was already small and genetically isolated. Even a limited number of kills—possibly just a few per year—could have pushed them over the edge. Moreover, climate on the island was stable during that period, so the final extinction is best explained by human activity, not a sudden environmental change.