Pika

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Pika1
Temporal range: Oligocene–Recent2
American pika (Ochotona princeps) in Sequoia National Park
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Lagomorpha
Family: Ochotonidae
Thomas, 1897
Genus: Ochotona
Link, 1795
Type species
Ochotona dauurica
Link, 1795
(Lepus dauuricus Pallas, 1776)
Species

See text

The pika (/ˈpkə/ PY-kə; archaically spelled pica) is a small mammal, with short limbs, rounded ears, and no external tail. The name pika is used for any member of the Ochotonidae, a family within the order of lagomorphs, which also includes the Leporidae (rabbits and hares). One genus, Ochotona, is recognised within the family, and it includes 30 species. It is also known as the "whistling hare" due to its high-pitched alarm call when diving into its burrow. The name "pika" appears to be derived from the Tungus piika.

Habitat

Collared pika on Hatcher Pass Alaska

Pikas are native to cold climates, mostly in Asia, North America and parts of Eastern Europe. Most species live on rocky mountain sides, where there are numerous crevices in which to shelter, although some pika also construct crude burrows. A few burrowing species are native to open steppe land. In the mountains of Eurasia, pikas often share their burrows with snowfinches, which build their nests there.3

Characteristics

Ochotona sp. fossils

Pikas are small mammals, with short limbs and small rounded ears. They are about 15 to 23 centimetres (5.9 to 9.1 in) in body length and weigh between 120 and 350 grams (4.2 and 12.3 oz), depending on species. Like rabbits, after eating they initially produce soft green feces, which they eat again to take in further nutrition, before producing the final, solid, fecal pellets. Some pikas, such as the collared pika, have been known to store dead birds in their burrows, for food during winter.4

These animals are herbivores, and feed on a wide variety of plant matter, including forbs, grasses, sedges, shrub twigs, moss, and lichen. As with other lagomorphs, pikas have gnawing incisors and no canines, although they have fewer molars than rabbits, giving them a dental formula of: 2.0.3.21.0.2.3

Rock-dwelling pikas have small litters of fewer than five young, while the burrowing species tend to give birth to more young, and to breed more frequently, possibly due to a greater availability of resources in their native habitats. The young are born after a gestation period of between 25 and 30 days.3

Activity

Vegetation pile, drying on rocks for subsequent storage. Gad Valley, Snowbird Ski Resort, Little Cottonwood Canyon, Utah
American pika with mouthful of dried grass. Sequoia National Park, CA

Pikas are diurnal or crepuscular, with higher-elevation species generally being more active during the daytime. They show their peak activity just before the winter season. Pikas do not hibernate, so they generally spend time during the summer collecting and storing food they will eat over the winter. Each rock-dwelling pika stores its own "haypile" of dried vegetation, while burrowing species often share food stores with their burrow mates. Haying behavior is more prominent at higher elevations. Many of the vocalizations and social behaviors that pikas exhibit are related to haypile defense.

Eurasian pikas commonly live in family groups and share duties of gathering food and keeping watch. At least some species are territorial. North American pikas (O. princeps and O. collaris) are asocial, leading solitary lives outside the breeding season.

Species

There are 30 species listed.

Extinct pikas

There are many known fossil forms of Ochotona described in the literature.

The "pusilla" group of pikas is characterized by archaic (plesiomorphic) cheek teeth and small size.6

The North American species migrated from Eurasia. They invaded the New World twice:

  • Ochotona spanglei during the latest Miocene or early Pliocene, followed by an approximately three million year long gap in the known North American pikas record.5
  • Ochotona whartoni (giant pika) and small pikas via the Bering Land Bridge during the earliest Pleistocene.5

Ochotona cf. whartoni and small pikas of the O. pusilla group are also known from Siberia. The extant, endemic North American species appeared in the Pleistocene. It has been suggested that the North American collared pika (O. collaris) and American pika (O. princeps) descended from the same ancestor as the steppe pika (O. pusilla).5

References

  1. ^ a b Hoffman, R. S.; Smith, A. T. (2005). "Order Lagomorpha". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. pp. 185–193. ISBN 978-0-8018-8221-0. OCLC 62265494. 
  2. ^ Savage, RJG, & Long, MR (1986). Mammal Evolution: an illustrated guide. New York: Facts on File. p. 128. ISBN 0-8160-1194-X. 
  3. ^ a b Kawamichi, Takeo (1984). Macdonald, D., ed. The Encyclopedia of Mammals. New York: Facts on File. pp. 726–727. ISBN 0-87196-871-1. 
  4. ^ http://animaldiversity.ummz.umich.edu/accounts/Ochotona_collaris/
  5. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af Erbajeva, Margarita A.; Mead, Jim I.; Alexeeva, Nadezhda V.; Angelone, Chiara; Swift, Sandra L. (2011). "Taxonomic diversity of Late Cenozoic Asian and North American ochotonids (an overview)". Palaeontologia Electronica (Society of Vertebrate Paleontology): 1–9. Retrieved April 13, 2014. 
  6. ^ a b c d e Erbajeva, Margarita A.; Mead, Jim I.; Swift, Sandra L. (2003). "Evolution and development of Asian and North American ochotonids". Occasional Papers in Earth Sciences No. 5 (Palaeontology Program Government of the Yukon): 33–34. Retrieved April 13, 2014. "3rd INTERNATIONAL MAMMOTH CONFERENCE, 2003: PROGRAM AND ABSTRACTS, Edited by John E. Storer" 
  7. ^ Rekovets, Leonid (2003). "Mammoth (Mammuthus primigenius) in the periglacial faunas of Ukraine". Occasional Papers in Earth Sciences No. 5 (Palaeontology Program Government of the Yukon): 130–131. Retrieved April 13, 2014. "3rd INTERNATIONAL MAMMOTH CONFERENCE, 2003: PROGRAM AND ABSTRACTS, Edited by John E. Storer" 
  8. ^ Shotwell, J. Arnold (1956). "Hemphillian mammalian assemblage from northeastern Oregon". Geological Society America Bulletin (Geological Society America) 67 (6): 717–738. doi:10.1130/0016-7606(1956)67[717:HMAFNO]2.0.CO;2. Retrieved April 19, 2014. 
  9. ^ "The Paleobiology Database. †Ochotona spanglei Shotwell 1956". Retrieved April 19, 2014. 
  10. ^ Guthrie, R.D.; Matthews, John V. Jr. (1971). "The Cape Deceit fauna—Early pleistocene mammalian assemblage from the Alaskan arctic". Quaternary Research 1 (4): 474–510. doi:10.1016/0033-5894(71)90060-3. Retrieved April 13, 2014. 
  11. ^ "The Paleobiology Database. †Ochotona whartoni Guthrie and Matthews, Jr. 1971 (pika)". Retrieved April 13, 2014. 

External links

The trek of the pika, by Michael Morris, Parks Canada, Mount Revelstoke and Glacier National Parks. Available at: http://cmiae.org/national-park-feature-article/the-trek-of-the-pika/. INCLUDES SOUND FILE.








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