Viết tích hợp TOEFL

📖 Đoạn văn

The extinction of the woolly mammoth has long been attributed to human hunting, but a closer examination of the evidence suggests that climate change was the primary driver. First, the timing of the mammoth’s disappearance correlates more strongly with the warming of the Holocene epoch than with human expansion. Mammoth populations declined sharply around 10,000 years ago, when temperatures rose and vegetation shifted from open steppe to dense forest—a change that predates the arrival of large-scale human hunters in many regions. Second, the dietary specialization of mammoths made them vulnerable to environmental change. Isotopic analyses of mammoth remains reveal that they relied almost exclusively on grasses and sedges. As these plants were replaced by trees and shrubs due to warming, the mammoths lost their primary food source, leading to malnutrition and reduced reproductive success. Third, paleontological data show that mammoth populations were already in decline before humans developed advanced hunting technologies. Fossil records from Wrangel Island indicate that isolated mammoth populations survived for thousands of years after human contact, but eventually succumbed during a period of rapid climate fluctuation. Thus, while humans may have delivered a final blow, climate change was the fundamental cause of their extinction.

🎧 Bài giảng

The reading presents a compelling case for climate change as the main cause of mammoth extinction, but it overlooks several key pieces of evidence that point to human hunting as the decisive factor. First, the timing argument is flawed. While the Holocene warming began about 11,700 years ago, mammoth populations actually thrived in warm interglacial periods before. They had adapted to warm climates in earlier epochs. What changed in the late Pleistocene was not just temperature, but the arrival of highly skilled human hunters with spears and coordinated strategies. Second, the dietary evidence is misleading. Although mammoths preferred grasses, they were not strict specialists. Modern elephants, their close relatives, are generalists that can shift diets. Coprolite and stomach content analyses show that mammoths consumed a variety of plants, including shrubs and tree bark, when available. So the shift to forest would not have caused starvation. Third, the Wrangel Island example actually supports human hunting. Those isolated populations survived until around 2000 BCE, but they disappeared shortly after humans first arrived on the island, not during a major climate shift. Similarly, on the mainland, the most rapid mammoth declines occurred in regions with the densest human populations, such as Eurasia and North America. Therefore, the evidence strongly suggests that human hunting was the primary cause, not climate change.