Mesonychidae
extinct family of mammals
Mesonychidae (meaning "middle claws") is an extinct family of small to large-sized omnivorous-carnivorous mammals and were one of the two families of the order Mesonychia. They were found in North America and Eurasia during the Early Paleocene to the Late Eocene. Once considered a sister-taxon to artiodactyls, recent evidence now suggests no close relation to any living mammal. Mesonychid taxonomy has long been disputed and they have captured popular imagination as "wolves on hooves", animals that combine features of both ungulates and carnivorans.
Taxonomy
Classification
Mesonychidae was named by Cope (1875), with its type genus, Mesonyx, being assigned to Carnivora. However, in a later paper, mesonychids would be moved to Creodonta by Cope (1880). In their 1966 paper, Van Valen recovered mesonychids from as Condylarthra. In their following paper, Van Valen would rank up mesonychids to an order known as Mesonychia, a consensus supported by all recent studies.
Relationship with Cetacea
Because skulls and teeth of mesonychids have similar features to early whales, and the family was long thought to be the ancestors of cetaceans. However, fossil discoveries have overturned this idea; the consensus is that whales are highly derived artiodactyls.
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This entry incorporates text from “Mesonychidae” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.