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 years earlier at the Miocene-Pliocene boundary.
Detailed fossil distribution
- Canada
- *Old Crow River, Yukon, Irvingtonian and Middle Pleistocene, O cf. whartoni and O. whartoni.
- *Old Crow River, Yukon, Late/Upper Pleistocene
- *Thistle Creek, Yukon, Middle Pleistocene, O. whartoni
- *Eagle Cave, Alberta, >33,000 BP
- *Elba Cave at Elba, Ontario, 8670±220 BP
- *Kelso Cave, Ontario, Late Wisconsian
- United States
- *Cape Deceit, Alaska, Cape Deceit Formation, Irvingtonian, O. whartoni,
- *Gold Hill Cut at Fairbanks, Alaska
- Russia - only O cf. whartoni
- *From eastern Siberia - Zayarsk site to the Kolyma Range area, in Kolyma from Late Cenozoic
- *Western Siberia, but mentions only Ochotona as occurring there.
Biology
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.