Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, 10115 Berlin, Germany.
GloCEE-Global Change Ecology and Evolution Research Group, Department of Life Sciences, Universidad de Alcalá, 28805 Alcalá de Henares, Madrid, Spain.
Science. 2023 Jun 9;380(6649):1076-1080. doi: 10.1126/science.add8366. Epub 2023 Jun 8.
Fossil abundance data can reveal ecological dynamics underpinning taxonomic declines. Using fossil dental metrics, we reconstructed body mass and mass-abundance distributions in Late Miocene to recent African large mammal communities. Despite collection biases, fossil and extant mass-abundance distributions are highly similar, with unimodal distributions likely reflecting savanna environments. Above 45 kilograms, abundance decreases exponentially with mass, with slopes close to -0.75, as predicted by metabolic scaling. Furthermore, communities before ~4 million years ago had considerably more large-sized individuals, with a greater proportion of total biomass allocated in larger size categories, than did later communities. Over time, individuals and biomass were redistributed into smaller size categories, reflecting a gradual loss of large-sized individuals from the fossil record paralleling the long-term decline of Plio-Pleistocene large mammal diversity.
化石丰度数据可以揭示导致分类衰退的生态动态。我们使用化石牙齿指标，重建了晚中新世至现代非洲大型哺乳动物群落的体重和质量丰度分布。尽管存在采集偏差，但化石和现存的质量丰度分布非常相似，单峰分布可能反映了稀树草原环境。在 45 公斤以上，丰度随质量呈指数下降，斜率接近-0.75，这与代谢比例预测的结果一致。此外，在大约 400 万年前之前的群落中，大型个体的数量要多得多，更大的体型类别分配了更大的生物量比例，而之后的群落则较少。随着时间的推移，个体和生物量重新分配到较小的体型类别中，反映出大型个体从化石记录中的逐渐消失，与上新世-更新世大型哺乳动物多样性的长期下降相吻合。
