Attenuated evolution of mammals through the Cenozoic

Goswami, A., Noirault, E., Coombs, E. J., Clavel, J., Fabre, A.-C., Halliday, T. J. D., Churchill, M., Curtis, A., Watanabe, A., Simmons, N. B., Beatty, B. L., Geisler, J. H., Fox, D. L., & Felice, R. N.

Attenuated evolution of mammals through the Cenozoic

2022

American Association for the Advancement of Science (AAAS)

Animals
Biological Evolution
Eutheria anatomy & histology
Female
Fossils
Index Medicus
Phylogeny
Rodentia
Skull anatomy & histology

English

The Cenozoic diversification of placental mammals is the archetypal adaptive radiation. Yet, discrepancies between molecular divergence estimates and the fossil record fuel ongoing debate around the timing, tempo, and drivers of this radiation. Analysis of a three-dimensional skull dataset for living and extinct placental mammals demonstrates that evolutionary rates peak early and attenuate quickly. This long-term decline in tempo is punctuated by bursts of innovation that decreased in amplitude over the past 66 million years. Social, precocial, aquatic, and herbivorous species evolve fastest, especially whales, elephants, sirenians, and extinct ungulates. Slow rates in rodents and bats indicate dissociation of taxonomic and morphological diversification. Frustratingly, highly similar ancestral shape estimates for placental mammal superorders suggest that their earliest representatives may continue to elude unequivocal identification.

Science, Volume 378, Issue 6618, October 2022, pages 377-383

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