Abstract:
:The biotic recovery from Earth's most severe extinction event at the Permian-Triassic boundary largely reestablished the preextinction structure of marine trophic networks, with marine reptiles assuming the predator roles. However, the highest trophic level of today's marine ecosystems, i.e., macropredatory tetrapods that forage on prey of similar size to their own, was thus far lacking in the Paleozoic and early Mesozoic. Here we report a top-tier tetrapod predator, a very large (>8.6 m) ichthyosaur from the early Middle Triassic (244 Ma), of Nevada. This ichthyosaur had a massive skull and large labiolingually flattened teeth with two cutting edges indicative of a macropredatory feeding style. Its presence documents the rapid evolution of modern marine ecosystems in the Triassic where the same level of complexity as observed in today's marine ecosystems is reached within 8 My after the Permian-Triassic mass extinction and within 4 My of the time reptiles first invaded the sea. This find also indicates that the biotic recovery in the marine realm may have occurred faster compared with terrestrial ecosystems, where the first apex predators may not have evolved before the Carnian.
journal_name
Proc Natl Acad Sci U S Aauthors
Fröbisch NB,Fröbisch J,Sander PM,Schmitz L,Rieppel Odoi
10.1073/pnas.1216750110subject
Has Abstractpub_date
2013-01-22 00:00:00pages
1393-7issue
4eissn
0027-8424issn
1091-6490pii
1216750110journal_volume
110pub_type
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