First filter feeding in the Early Triassic: cranial morphological convergence between Hupehsuchus and baleen whales

BMC Ecology and Evolution

Research

Jiang-Li Li¹  Ya-Rui Zou¹  Bi Zhao¹  Chun-Bo Yan²  Long Cheng²  Xu-Long Lai³  Zi-Chen Fang⁴  Michael J. Benton⁵  Li Tian⁶ 

[1] Hubei Institute of Geosciences, Hubei Geological Bureau, 430034, Wuhan, P. R. China;Hubei Key Laboratory of Paleontology and Geological Environment Evolution, Wuhan Center of China Geological Survey, 430205, Wuhan, P. R. China;School of Earth Sciences, China University of Geosciences, 430074, Wuhan, P. R. China;School of Earth Sciences, China University of Geosciences, 430074, Wuhan, P. R. China;Hubei Key Laboratory of Paleontology and Geological Environment Evolution, Wuhan Center of China Geological Survey, 430205, Wuhan, P. R. China;School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, BS8 1TQ, Bristol, UK;State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430078, Wuhan, P. R. China;

关键词: Nanzhang-Yuan’an Fauna;    Marine reptiles;    Ichthyosauromorph;    Mysticeti;    Mesozoic;   

DOI  :  10.1186/s12862-023-02143-9

 received in 2023-04-01, accepted in 2023-07-11,  发布年份 2023

来源: Springer

【 摘 要 】

Modern baleen whales are unique as large-sized filter feeders, but their roles were replicated much earlier by diverse marine reptiles of the Mesozoic. Here, we investigate convergence in skull morphology between modern baleen whales and one of the earliest marine reptiles, the basal ichthyosauromorph Hupehsuchus nanchangensis, from the Early Triassic, a time of rapid recovery of life following profound mass extinction. Two new specimens reveal the skull morphology especially in dorsal view. The snout of Hupehsuchus is highly convergent with modern baleen whales, as shown in a morphometric analysis including 130 modern aquatic amniotes. Convergences in the snout include the unfused upper jaw, specialized intermediate space in the divided premaxilla and grooves around the labial margin. Hupehsuchus had enlarged its buccal cavity to enable efficient filter feeding and probably used soft tissues like baleen to expel the water from the oral cavity. Coordinated with the rigid trunk and pachyostotic ribs suggests low speeds of aquatic locomotion, Hupehsuchus probably employed continuous ram filter feeding as in extant bowhead and right whales. The Early Triassic palaeoenvironment of a restrictive lagoon with low productivity drove Hupehsuchus to feed on zooplankton, which facilitated ecosystem recovery in the Nanzhang-Yuan’an Fauna at the beginning of the Mesozoic.

【 授权许可】

CC BY   
© The Author(s) 2023

【 图 表 】

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