The Mammoth Steppe was the dominant terrestrial biome of the Northern Hemisphere during the late Pleistocene. It encompassed a nonanalog community of animals living in a cold and treeless steppe-tundra landscape. The high diversity of species, including megafauna, could be supported by a productive environment. The carbon-13 and nitrogen-15 abundances in bone collagen confirmed that the coexistence of the large herbivores was facilitated by a pronounced dietary niche partitioning, with some species relatively flexible in the exploitation of browse and graze, while others were more specialized. The isotopic abundances of carbon and nitrogen in carnivores confirm a dietary partitioning, probably based on the size of prey, with an increasingly generalist behavior emerging after the Last Glacial Maximum with notable exceptions. Isotopic investigation reveals dynamic processes of ecological displacement and replacement, shedding new light on the potential niche spectrum of extant species that are now present as relic populations. ▪ The Mammoth Steppe is an extinct nonanalog ecosystem with high productivity and biodiversity despite the cold and dry conditions of the Last Glacial Period. ▪ Stable isotopes reveal that niche partitioning among herbivores and carnivores is a dominant trait of the Mammoth Steppe. ▪ Switches in preferred prey and ecological replacement are observed among carnivores over time, with the few highly specialized predators going extinct. ▪ Warmer and more humid conditions preceding the Holocene impacted large herbivores in most regions of the Mammoth Steppe, driving some of the largest ones to extinction.

中文翻译：

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猛犸草原的同位素生态学


猛犸草原是更新世晚期北半球的主要陆地生物群落。它包括生活在寒冷、没有树木的草原苔原景观中的非类比动物群落。丰富的环境可以支持包括巨型动物在内的物种的高度多样性。骨胶原中碳 13 和氮 15 的丰度证实，明显的饮食生态位划分促进了大型食草动物的共存，其中一些物种在浏览和放牧方面相对灵活，而其他物种则更加专业化。食肉动物中碳和氮的同位素丰度证实了饮食分配，可能基于猎物的大小，在末次盛冰期之后出现了越来越普遍的行为，但有明显的例外。同位素研究揭示了生态位移和替代的动态过程，为目前作为遗迹种群存在的现存物种的潜在生态位谱提供了新的线索。 ▪ 猛犸草原是一个已灭绝的非类比生态系统，尽管末次冰期气候寒冷干燥，但仍具有高生产力和生物多样性。 ▪ 稳定同位素表明，食草动物和食肉动物之间的生态位划分是猛犸草原的一个显着特征。 ▪ 随着时间的推移，我们观察到食肉动物的首选猎物和生态替代发生了变化，少数高度专业化的捕食者灭绝了。 ▪ 全新世之前更温暖、更潮湿的环境影响了猛犸草原大部分地区的大型食草动物，导致一些最大的食草动物灭绝。