Viết tích hợp TOEFL

📖 Đoạn văn

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 mammoth extinction coincides with the rapid warming at the end of the last Ice Age, around 10,000 years ago. As temperatures rose, their grassland habitats shrank, replaced by forests and tundra, reducing their food supply. Second, genetic studies show that mammoth populations were already declining long before humans reached their main habitats in Siberia and North America. This decline correlates with earlier interglacial warming periods, not with human arrival. Third, isolated populations, such as those on Wrangel Island, survived for thousands of years after human hunting had become widespread, indicating that human pressure alone was not sufficient to cause extinction. Instead, these final populations only vanished when environmental conditions became too extreme, such as during abrupt sea-level rise and vegetation changes.

🎧 Bài giảng

The reading argues that climate change, not humans, killed the woolly mammoth, but this view is flawed. First, while warming did alter habitats, mammoths were adaptable grazers that coexisted with forests and tundra in many regions. In fact, their fossils have been found in diverse environments, and they likely consumed a wide range of plants, not just grass. Second, the genetic evidence of pre-human decline is misleading. Those earlier population dips occurred during natural climate cycles, but the final extinction event happened precisely when humans arrived with advanced hunting tools, such as spears and traps. The correlation with human expansion is far stronger than with any climate shift. Third, the Wrangel Island population actually undermines the climate argument: these mammoths survived through the same dramatic climate changes that supposedly killed others. Their extinction around 4,000 years ago coincides with the arrival of humans on the island, and archaeological evidence shows butchering of mammoth remains. Thus, human hunting was the decisive factor, not climate.