The extinction of the woolly mammoth has long been attributed to overhunting by early humans. This 'Pleistocene overkill' hypothesis rests on three main arguments. First, the timing of mammoth extinctions across different continents correlates closely with the arrival of human hunters. For example, mammoths disappeared from North America around 13,000 years ago, shortly after the Clovis people appeared. Second, archaeological sites have yielded spear points and butchered mammoth bones, providing direct evidence of human predation. At sites like Lehner Ranch in Arizona, mammoth remains are found alongside Clovis artifacts, suggesting that hunting was a significant activity. Third, mammoths had no prior experience with human predators, making them easy targets. Like modern island species that go extinct when humans arrive, mammoths likely exhibited naive behavior, allowing even small human populations to drive them to extinction rapidly. This combination of chronological coincidence, archaeological evidence, and behavioral vulnerability makes a compelling case that human hunting was the primary cause of mammoth extinction.
🎧 听力讲座
🎯 模拟考试环境：先点「播放讲座」听完内容，再作答。听力原文默认隐藏。
While the reading presents a plausible story, it suffers from serious weaknesses. First, the correlation between human arrival and mammoth extinction is not as clean as claimed. In Eurasia, humans coexisted with mammoths for over 30,000 years before the final extinction, and in some regions, mammoths disappeared thousands of years before humans arrived. This temporal mismatch undermines the idea that human arrival was the trigger. Second, the archaeological evidence is far from conclusive. Butchered mammoth bones are rare and often show signs of scavenging rather than active hunting. At many sites, cut marks are absent, and the bones may have been naturally deposited. Even where artifacts are found, they could represent opportunistic use of already dead animals. Third, the behavioral naivety argument ignores evidence that mammoths were not completely defenseless. Cave paintings and fossilized footprints suggest that mammoths lived in herds with complex social structures, and adults were large and formidable. Moreover, island dwarf mammoths, which were smaller, survived on Wrangel Island until 4,000 years ago, long after humans had reached the mainland. If human hunting were the sole cause, these isolated populations should have been even more vulnerable, yet they persisted for millennia. Thus, the reading's three points are not supported by a careful examination of the evidence.
📝 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.
