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Why were many large mammals extinct by the end of the Pleistocene?
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Quaternary
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the Quaternary Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The extinction of many large mammals at the end of the Pleistocene Epoch remains a subject of vigorous scientific debate, with no single consensus on the cause. Instead, researchers generally point to a combination of factors that likely varied in importance across different geographic regions.12
Two primary hypotheses are typically advanced:
- The Overkill Hypothesis: This theory suggests that the arrival of skilled human hunters—such as those associated with the Clovis complex—led to the rapid depletion of large herbivores that were unaccustomed to human predation. The subsequent decline of these prey species would have also impacted large carnivores.12
- Climatic and Environmental Change: This hypothesis focuses on the abrupt climatic changes during the last glacial-interglacial transition. These shifts caused significant reorganization of vegetation, altered food availability, and increased environmental stress as climates became more seasonal.12
Ultimately, it is likely that these extinctions resulted from a complex interplay between human activities and environmental disruption, with the relative impact of each factor differing depending on the specific conditions of the region.1