The extinction of the woolly mammoth has long been attributed to overhunting by early humans. This theory, known as the 'Pleistocene overkill hypothesis,' argues that human hunters, armed with advanced tools and cooperative strategies, drove these massive creatures to extinction as they migrated into new territories. Three main lines of evidence support this view. First, the timing of mammoth extinctions correlates with the arrival of humans in different regions. In North America, for example, mammoths disappeared shortly after the Clovis people appeared around 13,000 years ago. Second, archaeological sites often contain mammoth bones with cut marks and embedded spear points, indicating active hunting. At sites like the Murray Springs Clovis site in Arizona, remains of mammoths have been found alongside distinctive Clovis projectile points. Third, the mammoth's life history made it especially vulnerable to hunting. Mammoths had long gestation periods and produced few offspring, meaning that even modest levels of hunting could outpace their reproductive rates, leading to population decline and eventual extinction.
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While the overkill hypothesis is popular, it fails to withstand scrutiny. First, the temporal correlation between human arrival and mammoth extinction is not consistent. In Siberia, mammoths survived for thousands of years after humans arrived, and on Wrangel Island, a dwarf population persisted until 4,000 years ago, long after humans had established presence nearby. Second, the archaeological evidence is ambiguous. Many mammoth bones with 'cut marks' may actually show marks from natural processes, such as trampling by other animals or weathering, which can mimic butchering damage. Moreover, the number of mammoth kill sites is extremely small—only a handful across the entire continent—hardly sufficient to demonstrate a widespread hunting pressure. Third, the reproductive argument is flawed because it ignores the mammoth's ability to adapt. Population modeling shows that even with low reproductive rates, mammoths could sustain moderate levels of hunting if their environment provided adequate resources. The real culprit, as recent climate studies suggest, was the rapid warming at the end of the last Ice Age, which shrank their grassland habitats and fragmented populations, making them more susceptible to disease and starvation, not human spears.
📝 작문 지시 Summarize the points made in the lecture, being sure to explain how they cast doubt on the specific points made in the reading passage.
📊 TOEFL Integrated Writing Rubric
Content Accuracy: Accurately capture the relationship between lecture and reading
Information Completeness: Cover all key counter-arguments from the lecture
Structure & Coherence: Logical organization and progression
Language Use: Grammar, vocabulary, expression accuracy
Scored 0-30 based on holistic scoring (original 0-5, scaled to 30).
