The extinction of the woolly mammoth has long been attributed to overhunting by early humans. However, recent evidence suggests that climate change was the primary driver. First, the warming climate at the end of the Pleistocene reduced the mammoth's grassland habitat. As forests expanded, mammoths, which were adapted to cold steppe environments, lost their food sources and open spaces. Second, rising sea levels isolated populations on islands, such as Wrangel Island, where small groups faced inbreeding and reduced genetic diversity, making them vulnerable to disease and environmental shifts. Third, the timing of extinction correlates with major climatic events, not human arrival. For example, mammoths survived on Wrangel Island until 4,000 years ago, long after humans had reached the mainland, but their disappearance coincided with a period of rapid warming and vegetation change. Thus, climate change, not human hunting, explains their demise.
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The reading's claim that climate change alone drove mammoth extinction is flawed. While habitat loss was a factor, humans played a decisive role. First, archaeological sites show that early humans actively hunted mammoths, with spear points embedded in bones and butchery marks. This direct evidence indicates that hunting pressure was significant, especially as human populations grew and weaponry improved. Second, the Wrangel Island example actually supports human involvement: despite isolation, the small mammoth population persisted for thousands of years, suggesting they could adapt to environmental stress. Their eventual extinction around 4,000 years ago coincides with the arrival of humans on the island, not with a unique climatic event. Third, climate change was gradual, allowing species to migrate or adapt. Yet mammoths disappeared rapidly across their range, which points to a sudden, external cause—human overhunting. Moreover, similar large mammals, like bison, survived the same climate shifts, indicating that climate was not the primary killer. Therefore, human hunting was the critical factor in the mammoth's extinction.
📝 Инструкция по письму Summarize the points made in the lecture, being sure to explain how they cast doubt on the specific points made in the reading passage.
📊 TOEFL Integrated Writing Rubric
Content Accuracy: Accurately capture the relationship between lecture and reading
Information Completeness: Cover all key counter-arguments from the lecture
Structure & Coherence: Logical organization and progression
Language Use: Grammar, vocabulary, expression accuracy
Scored 0-30 based on holistic scoring (original 0-5, scaled to 30).
