The extinction of the woolly mammoth has long been attributed to overhunting by early humans. Proponents of this 'Pleistocene overkill' hypothesis argue that human hunters, equipped with advanced tools and cooperative strategies, drove these massive herbivores to extinction shortly after migrating into their habitats. First, archaeological sites in North America and Eurasia contain mammoth bones with cut marks and embedded projectile points, indicating direct human predation. Second, the timing of mammoth extinctions correlates closely with human arrival in different regions—for example, they disappeared from mainland Alaska within a few centuries of human settlement. Third, mammoths had low reproductive rates, making their populations especially vulnerable to even modest increases in adult mortality caused by hunting. Thus, human hunting appears to be the primary driver of their demise.
🎧 听力讲座
The reading's claim that humans alone wiped out the mammoths is overly simplistic. While some evidence of hunting exists, it does not prove overkill. First, the cut marks on bones are rare and often ambiguous; many could result from scavenging carcasses of mammoths that died of other causes. In fact, at most sites, the number of killed individuals is too small to account for a population collapse. Second, the correlation between human arrival and extinction is not consistent. In some regions, such as Siberia, mammoths survived for thousands of years after humans were present, and in others, like Wrangel Island, they persisted until 2000 BC—long after human contact. This suggests other factors were at play. Third, the argument about low reproductive rates ignores that mammoths were resilient animals that had survived multiple climate fluctuations. The most compelling explanation is rapid climate warming at the end of the last ice age, which shrank their grassland habitat, disrupted their food supply, and fragmented populations. Human hunting may have delivered the final blow to already stressed populations, but it was not the sole cause.
📝 写作提示 Summarize the points made in the lecture, being sure to explain how they cast doubt on the specific points made in the reading passage.