title: Lunge feeding in early marine reptiles and fast evolution of marine tetrapod feeding guilds.
abstract: Traditional wisdom holds that biotic recovery from the end-Permian extinction was slow and gradual, and was not complete until the Middle Triassic. Here, we report that the evolution of marine predator feeding guilds, and their trophic structure, proceeded faster. Marine reptile lineages with unique feeding adaptations emerged during the Early Triassic (about 248 million years ago), including the enigmatic Hupehsuchus that possessed an unusually slender mandible. A new specimen of this genus reveals a well-preserved palate and mandible, which suggest that it was a rare lunge feeder as also occurs in rorqual whales and pelicans. The diversity of feeding strategies among Triassic marine tetrapods reached their peak in the Early Triassic, soon after their first appearance in the fossil record. The diet of these early marine tetrapods most likely included soft-bodied animals that are not preserved as fossils. Early marine tetrapods most likely introduced a new trophic mechanism to redistribute nutrients to the top 10 m of the sea, where the primary productivity is highest. Therefore, a simple recovery to a Permian-like trophic structure does not explain the biotic changes seen after the Early Triassic.
authors.affiliation: Department of Earth and Planetary Sciences, University of California, Davis, One Shields Avenue, Davis, California 95616, U.S.A.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Motani
authors.affiliation: Wuhan Centre of China Geological Survey, Wuhan, Hubei 430023, P. R. China.
authors.forename: Xiao-hong
authors.initials: XH
authors.lastname: Chen
authors.affiliation: Laboratory of Orogenic Belt and Crustal Evolution, Ministry of Education; Department of Geology and Geological Museum, Peking University, Yiheyuan Street. 5, Beijing 100871, P.R. China.
authors.forename: Da-yong
authors.initials: DY
authors.lastname: Jiang
authors.affiliation: Wuhan Centre of China Geological Survey, Wuhan, Hubei 430023, P. R. China.
authors.forename: Long
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Dipartimento di Scienze della Terra, Università degli Studi di Milano, Via Mangiagalli 34-20133 Milano, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Tintori
authors.affiliation: Center of Integrative Research, The Field Museum, Chicago. IL 60605-2496, U.S.A.
authors.forename: Olivier
authors.initials: O
authors.lastname: Rieppel
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D059001:Aquatic Organisms; D005075:Biological Evolution; D017753:Ecosystem; D005247:Feeding Behavior; D005580:Fossils; D010163:Paleontology; D010802:Phylogeny; D011235:Predatory Behavior; D012104:Reptiles; D014907:Whales