Abstract
The role of climate change in the origin and diversification of early hominins is hotly debated. Most accounts of early hominin evolution link observed fluctuations in species diversity to directional shifts in climate or periods of intense climatic instability. None of these hypotheses, however, have tested whether observed diversity patterns are distorted by variation in the quality of the hominin fossil record. Here, we present a detailed examination of early hominin diversity dynamics, including both taxic and phylogenetically corrected diversity estimates. Unlike past studies, we compare these estimates to sampling metrics for rock availability (hominin-, primate-, and mammal-bearing formations) and collection effort, to assess the geological and anthropogenic controls on the sampling of the early hominin fossil record. Taxic diversity, primate-bearing formations, and collection effort show strong positive correlations, demonstrating that observed patterns of early hominin taxic diversity can be explained by temporal heterogeneity in fossil sampling rather than genuine evolutionary processes. Peak taxic diversity at 1.9 million years ago (Ma) is a sampling artifact, reflecting merely maximal rock availability and collection effort. In contrast, phylogenetic diversity estimates imply peak diversity at 2.4 Ma and show little relation to sampling metrics. We find that apparent relationships between early hominin diversity and indicators of climatic instability are, in fact, driven largely by variation in suitable rock exposure and collection effort. Our results suggest that significant improvements in the quality of the fossil record are required before the role of climate in hominin evolution can be reliably determined.
Funder
RCUK | Natural Environment Research Council
Publisher
Proceedings of the National Academy of Sciences
Reference71 articles.
1. Darwin CR (1859) On the Origin of Species by Means of Natural Selection (John Murray, London).
2. Wood BA Grabowski MW (2015) Macroevolution in and around the hominin clade. Macroevolution: Explanation, Interpretation and Evidence, eds Serrelli E Gontier N (Springer, Cham, Switzerland), pp 345–376.
3. Mosaic evolution and the pattern of transitions in the hominin lineage
4. Vrba ES (1995) The fossil record of African antelopes (Mammalia, Bovidae) in relation to human evolution and paleoclimate. Paleoclimate and Evolution, with Emphasis on Human Origins, eds Vrba ES Denton GH Partridge TC Burckle LH (Yale Univ Press, New Haven, CT), pp 385–424.
5. Plio-Pleistocene African Climate
Cited by
18 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献