''Peregocetus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of early whale that lived in what is now

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

during the

Middle Eocene The Eocene ( ) is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''Ēṓs'', ' Dawn') a ...

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided b ...

. Its fossil was uncovered in 2011 in the Yumaque Member ( Paracas Formation) of the

Pisco Basin Pisco Basin () is a sedimentary basin extending over in southwestern Peru.Solís Mundaca, 2018, p.1 The basin has a 2-kilometre (1.25-mile) thick sedimentary fill, which is about half the thickness of more northern foreland basins in Peru. The o ...

at Playa Media Luna by a team consisting of members from

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

, and the

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

. Parts recovered include the jaw, front and hind legs, bits of spine, and tail. Olivier Lambert, a scientist at the

Royal Belgian Institute of Natural Sciences The Museum of Natural Sciences (, ; , ) is a Brussels museum dedicated to natural history. It is a part of the Royal Belgian Institute of Natural Sciences (; ), itself part of the institutions of the Belgian Federal Science Policy Office (BELSP ...

and lead author of the study, noted that ''Peregocetus'' "fills in a crucial nowledgegap" about the evolution of whales and their spread. ''Peregocetus'' is the first recorded quadrupedal whale from the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

and the Southern Hemisphere. The discovery reveals that protocetids reached the Pacific Ocean and attained a near circumequatorial distribution while retaining functional weight-bearing limbs.

Description

''Peregocetus'' was essentially a four-legged whale: however, it had webbed feet with small hooves on the tips of its toes, making it more capable of moving on land than modern seals. It featured sharp teeth and a long snout which suggests it fed on fish and/or crustaceans. From its caudal vertebrae, it has been suggested that it might have possessed a flattened tail similar to a

beaver Beavers (genus ''Castor'') are large, semiaquatic rodents of the Northern Hemisphere. There are two existing species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers are the second-large ...

References

{{Taxonbar, from=Q62834728 Protocetidae Lutetian life Eocene mammals of South America Paleogene Peru Fossils of Peru Fossil taxa described in 2019