Soru

Passage A
The debate surrounding the terminal Pleistocene extinction of North American megafauna has long pitted anthropogenic hunting against climatic upheaval. Proponents of the blitzkrieg overkill hypothesis assert that human arrival via the Beringian corridor introduced a novel predatory pressure against which naive megaherbivores possessed no evolutionary defenses. Recent advances in ultrafiltration radiocarbon dating and chronometric hygiene have strengthened this position by narrowing the temporal gap between the emergence of Clovis fluted-point technology and the sudden disappearance of genera such as Mammut and Smilodon. Rather than a protracted, gradual decline across millennia, the fossil record reveals a catastrophic collapse concentrated within a few centuries immediately following human colonization. Critics who emphasize climate fluctuations fail to explain why these species survived multiple prior glacial-interglacial cycles of comparable severity over the preceding two million years only to vanish precisely when human hunters expanded across the continent. Although environmental stresses may have altered local habitats, the suddenness and taxonomic selectivity of the extinctions—overwhelmingly targeting large-bodied mammals with low reproductive turnover—bear the unmistakable signature of targeted human predation.

Passage B
The attribution of Late Quaternary megafaunal extinctions primarily to human overkill relies on a seductive but oversimplified correlation. High-resolution sedimentary pollen cores and ancient environmental DNA reveal that the terminal Pleistocene was characterized by unprecedented ecological dislocation. During the transition from the Bølling-Allerød interstadial to the abrupt cooling of the Younger Dryas, floral communities underwent radical restructuring. The vast, heterogeneous mosaic of steppe-tundra—rich in diverse, high-nutrient forage—collapsed into homogenous, nutrient-poor boreal forests and open peatlands. This biome fragmentation severed the critical dietary niches of specialized megaherbivores, precipitating cascading demographic crashes across trophic webs. Proponents of human overkill overlook the profound nutritional vulnerability of large herbivores during this floral reorganization; reduced carrying capacities would have rendered populations unviable even in the total absence of hunting. While early human populations undoubtedly hunted megafauna when opportunities arose, the archaeological record exhibits remarkably few unambiguous kill sites relative to the continental scale of the extinctions. Anthropogenic predation acted, at most, as an opportunistic, secondary stressor upon populations already doomed by rapid climatic and vegetational deterioration.

Based on the passages, which of the following statements express claims that BOTH Author A and Author B would endorse? (Select all that apply.)