Escritura integrada TOEFL

📖 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 mammoth decline correlates with the end of the last Ice Age, when temperatures rose dramatically. As forests expanded and grasslands shrank, the mammoth’s steppe habitat disappeared, reducing food availability. Second, genetic studies show that mammoth populations experienced severe bottlenecks long before humans arrived in their final refuges, indicating that climate-driven habitat fragmentation weakened their numbers. Third, human hunting pressure was likely too low to cause extinction; archaeological sites with mammoth bones are rare, and early human populations were small. Thus, while humans may have delivered a final blow, the woolly mammoth was already doomed by environmental changes.

🎧 Conferencia de audio

The reading’s argument is flawed. First, the correlation between warming and mammoth decline does not prove causation. In fact, mammoths survived several interglacial warm periods before the last one, so warmth alone cannot explain their extinction. Second, the genetic bottlenecks the reading cites actually occurred during earlier glacial maxima, not during the final warming phase, and these bottlenecks were followed by population recoveries. The critical decline happened precisely when human hunters migrated into Siberia and North America. Third, the scarcity of mammoth bones at archaeological sites is misleading—many kill sites may have been destroyed by glacial processes, and human populations were larger and more organized than the reading assumes. Moreover, evidence of spear points embedded in mammoth ribs and the use of mammoth bones for tools and dwellings clearly indicates significant hunting pressure. Therefore, human overhunting, not climate, was the decisive factor.