''Podiceps oligoceanus'' is an extinct species of

grebe Grebes () are aquatic diving birds in the order (biology), order Podicipediformes (). Grebes are widely distributed freshwater birds, with some species also found in sea, marine habitats during Bird migration, migration and winter. Most grebes f ...

possibly from the

Neogene The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of th ...

period which the specimen has been found in the United States.

History

The species was part of a major paper that was commissioned by professor Charles Schuchert in 1914 in which he had

Robert Wilson Shufeldt Robert Wilson Shufeldt Jr. (December 1, 1850January 21, 1934) was an American osteologist, myologist, museologist and ethnographer who contributed to comparative studies of bird anatomy and forensic science. He hated black people, strongly a ...

for revision of the type specimens of fossil birds that were described by

Othniel Charles Marsh Othniel Charles Marsh (October 29, 1831 – March 18, 1899) was an American professor of paleontology. A prolific fossil collector, Marsh was one of the preeminent paleontologists of the nineteenth century. Among his legacies are the discovery or ...

for the

Peabody Museum of Natural History The Peabody Museum of Natural History at Yale University (also known as the Yale Peabody Museum of Natural History or the Yale Peabody Museum) is one of the oldest, largest, and most prolific university natural history museums in the world. It ...

Description

The

femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femo ...

of the holotype ( YPM 983) is similar to grebes of the genus ''

Aechmophorus ''Aechmophorus'' is a genus of birds in the grebe family. Species It has two living representatives breeding in western North America. One prehistoric species has been described from fossil remains: *'' Aechmophorus elasson'' (Late Plio ...

'' and the

red-necked grebe The red-necked grebe (''Podiceps grisegena'') is a migratory aquatic bird found in the temperate regions of the northern hemisphere. Its wintering habitat is largely restricted to calm waters just beyond the waves around ocean coasts, althoug ...

(''P. grisegena''), though the shaft is slender and heavier.

Classification

Initially the species was placed in the now defunct genus '' Colymbus'' by Shufeldt (1915) (''Colymbus oligoceanus''), it has since been reclassified into the genus ''

Podiceps ''Podiceps'' is a genus of birds in the grebe family. The genus name comes from Latin , "rear-end" and ', "foot", and is a reference to the placement of a grebe's legs towards the rear of its body. It has representatives breeding in all contine ...

''.

Paleobiology

The holotype femur was found at the

John Day Fossil Beds National Monument John Day Fossil Beds National Monument is a U.S. national monument in Wheeler and Grant counties in east-central Oregon. Located within the John Day River basin and managed by the National Park Service, the park is known for its well-preserve ...

. The age of ''P. oligoceanus'' is uncertain. Shufeldt (1915) tentatively assign the species of

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

age, while Brodkorb (1963) believed the species is of

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

age. There are doubts, however, that ''P. oligoceanus'' could also be from the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

epoch due to how similar it is to modern grebes.

References

{{Taxonbar, from=Q116008472 oligoceanus Fossil taxa described in 1915 Birds described in 1915