The extinction of the woolly mammoth, a species that roamed the Earth during the Pleistocene, has been a subject of scientific debate. While many researchers attribute their disappearance to human hunting, a closer look at the evidence suggests that climate change and habitat loss were the primary drivers. First, the warming climate at the end of the last Ice Age reduced the mammoth’s preferred habitat—cold, dry grasslands known as the steppe-tundra. As temperatures rose, these vast grasslands were replaced by forests and peatlands, which were unsuitable for mammoths. Second, the shrinking habitat led to fragmented populations, which reduced genetic diversity and increased inbreeding. This made mammoths more vulnerable to disease and less able to adapt to environmental pressures. Finally, the timing of mammoth extinctions on isolated islands, such as Wrangel Island, does not align with human arrival. On Wrangel Island, mammoths survived until around 2000 BCE, thousands of years after human settlement, suggesting that climate, not hunting, was the key factor.
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The reading’s argument that climate change caused the woolly mammoth’s extinction is not convincing. First, while the warming climate did alter habitats, human hunting was the decisive factor. For instance, in North America, mammoths disappeared around 10,000 years ago, coinciding with the arrival of Clovis hunters, but after a period of stable climate. If climate were the cause, we would expect extinctions to occur during rapid warming events, but the fossil record shows no such correlation. Second, genetic evidence from fragmented populations actually supports the hunting hypothesis. When human hunters killed mammoths in one area, the remaining small populations became isolated and inbred, but this was a consequence of hunting, not a cause of extinction. Finally, the case of Wrangel Island is misleading. Radiocarbon dating shows that mammoths there went extinct shortly after humans first arrived on the island, around 1700 BCE, not thousands of years later. Moreover, climate on Wrangel remained stable during that period, so human hunting is the only plausible explanation.
📝 Writing Prompt 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).
