Giant pika


The giant pika or Wharton's pika is an extinct mammal species in the family Ochotonidae. It lived during the Pleistocene and early Holocene in northern parts of North America. Very similar forms have also been found also in Siberia.

Distribution

The giant pika has been found in Alaska, Yukon, Alberta and Ontario. A close relative O. whartoni is also known from Eastern Siberia and Kolyma.
The ancestors of these pikas migrated from Eurasia to North America during the Early Pleistocene via the Bering Land Bridge, along with another group of small pikas close to the "O. pusilla group". This migration was separate from that of O. spanglei, which entered North America approximately three million earlier at the Miocene-Pliocene boundary.

Detailed fossil distribution

, at least 10 locations, O. cf. whartoni

The giant pika is much larger than other North American pikas, but is of a similar size to the extinct early and middle Pleistocene O. complicidens and extant O. koslowi, both from China, and may belong to one of them. Unlike the American pika, which inhabits scree slopes, the giant pika's habitat was largely tundra and steppe, similar to Eurasian pikas.

Occurrence and extinction

The giant pika has been found in North America from the Irvingtonian throughout Middle Pleistocene to Late Pleistocene locations.
The last occurrence of the giant pika is known from early the Holocene of eastern North America and its radiometric date is 8670±220 years BP or 10251-9140 BP. It is possible that it survived in the rocky areas along the Niagara Escarpment as a relict population.

Additional references of the Paleobiology Database