Pika

Pika[1] Temporal range: Miocene-Holocene, 16.4–0 Ma[2] PreЄ Є O S D C P T J K Pg N
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 daurica Link, 1795 (Lepus dauuricus Pallas, 1776)
Species
See text
Pika Ochotona sp. fossil distribution. Extinct pikas and Ochotona indet. are red, steppe pika O. pusilla blue, northern pika O. hyperborea green, other extant pikas black.[2][3][n 1]

A pika (/ˈpaɪkə/ PY-kə; archaically spelled pica) is a small mammal, with short limbs, very round body, 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. In the United States, the pika is colloquially called a "coney", a nonspecific term also used for rabbits, hares and hyraxes.^[4] 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 numerous crevices in which to shelter occur, although some pikas 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.^[5]

Characteristics

Ochotona sp. fossils

Pikas are small mammals, with short limbs and 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.^[6]

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.^[5]

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. Some species are territorial. North American pikas (O. princeps and O. collaris) are asocial, leading solitary lives outside the breeding season.

Dialects

Pikas have distinct calls that vary in duration. The call can either be short and quick, or a little longer and drawn out, or songs. The short calls are an example of geographic variation. The pikas determined the appropriate time to make short calls by listening for cues for sound localization.^[7] The calls are used as either a warning signals or as a way to attract the opposite gender. There are also different calls depending on the type of season. In the spring, the calls, songs, became more frequent due to the breeding season. In late summer, the vocalizations became short calls. Through various studies, the vocalizations mark that the calls can be used as a taxonomic tool.^[8]

Lifespan

The average lifespan in pikas is roughly around 7 years in the wild. In order to determine how old a pika is, one would have to count the adhesion lines on the periosteal bone on the lower jaw. The lifespan does not differ between the sexes.^[9]

Species

There are 30 species listed.

• Order Lagomorpha^[1]
  • Family Ochotonidae: pikas
    • Genus Ochotona
      • Subgenus Pika: northern pikas
        • Alpine pika/Altai Pika, Ochotona alpina
        • Helan Shan pika or Silver pika, Ochotona argentata
        • Collared pika, Ochotona collaris
        • Hoffmann's pika, Ochotona hoffmanni
        • Northern pika/Siberian pika, Ochotona hyperborea
        • Pallas's pika, Ochotona pallasi
        • American pika, Ochotona princeps
        • Turuchan pika, Ochotona turuchanensis
      • Subgenus Ochotona: shrub-steppe pikas
        • Gansu pika/Gray pika, Ochotona cansus
        • Plateau pika/Black-lipped pika, Ochotona curzoniae
        • Daurian pika, Ochotona dauurica
        • Tsing-ling pika, Ochotona huangensis
        • Nubra pika, Ochotona nubrica
        • Steppe pika, Ochotona pusilla
        • Afghan pika, Ochotona rufescens
        • Moupin pika, Ochotona thibetana
        • Thomas's pika, Ochotona thomasi
      • Subgenus Conothoa: mountain pikas
        • Chinese red pika, Ochotona erythrotis
        • Forrest's pika, Ochotona forresti
        • Gaoligong pika, Ochotona gaoligongensis
        • Glover's pika, Ochotona gloveri
        • Himalayan pika, Ochotona himalayana
        • Ili pika, Ochotona iliensis
        • Koslov's pika, Ochotona koslowi
        • Ladak pika, Ochotona ladacensis
        • Large-eared pika, Ochotona macrotis
        • Muli pika, Ochotona muliensis
        • Black pika, Ochotona nigritia
        • Royle's pika, Ochotona roylei
        • Turkestan red pika, Ochotona rutila

Extinct pikas

There are many known fossil forms of Ochotona described in the literature, from the Miocene epoch to the early Holocene (extinct species) and present (16.4-0 Ma^[2]). They lived in Europe, Asia, and North America. Note that some species listed below are common for Eurasia and North America (O. gromovi, O. tologoica, O. zazhigini and probably O. whartoni).

• Eurasia
  • large forms
    • †Ochotona chowmincheni (China: Baode area, late Miocene)^[2][10][11]
    • †Ochotona gromovi (Asia, Pliocene, see also North America)^[11]
    • †Ochotona gudrunae (China: Shanxi, early Pleistocene)^[2][10][11]
    • †Ochotona guizhongensis (Tibet, late Miocene)^[2][11][12]
    • †Ochotona lagreli (China: Inner Mongolia, late Miocene to late Pliocene)^{[2][10][11][12]}
    • †Ochotona magna (China, early Pleistocene)^[2][11][13]
    • †Ochotona tologoica (Transbaikalia, Pliocene, see also North America)^[2][11][13]
    • †Ochotona transcaucasica (Transcaucasia: eastern Georgia and Azerbaijan, Transbaikal and probably southern Europe, early to late Pleistocene)^[2][10][11]
    • †Ochotona ursui (Romania, Pliocene)^[2][11]
    • †Ochotona zasuchini (Transbaikalia, Pleistocene)^[2][11][13]
    • †Ochotona zazhigini (Asia, Pliocene, see also North America)^[2][11]
    • †Ochotona zhangi (China, Pleistocene)^[2][11][13]
  • medium-sized forms
    • †Ochotona agadjianiani (Asia, Pliocene)^[11]
    • †Ochotona antiqua (Moldavia, Ukraine and the Russian Plain, Caucasus, and probably Rhodes, late Miocene to Pliocene)^[2][10][11]
    • †Ochotona azerica (Transcaucasia: Azerbaijan,^[14] middle Pliocene)^[2][13]
    • †Ochotona lingtaica (Asia, Pliocene)^[2][11]
    • †Ochotona dodogolica (Asia: western Transbaikalia, Pleistocene)^[10][11]
    • †Ochotona nihewanica (China: Hebei, early Pleistocene)^{[2][10][11][15]}
    • †Ochotona plicodenta (Asia, Pliocene)^[2][11]
    • †Ochotona polonica (Europe: Poland, Germany, France, Pliocene)^[2][10][11]
  • small-sized forms
    • †Ochotona bazarovi (Asia, upper Pliocene)^[2][13][15]
    • †Ochotona dehmi (Germany: Schernfeld, Pleistocene)^[2][11]
    • †Ochotona filippovi (Siberia, Pleistocene)^[2][15]
    • †Ochotona gracilis (Asia, Pliocene)^[2][11]
    • †Ochotona horaceki (Slovakia: Honce, Pleistocene)^[2][11]
    • †Ochotona minor (China, late Miocene)^[2][11][12]
    • †Ochotona sibirica (Asia, Pliocene)^[2][11]
    • †Ochotona valerotae (France: Valerots site, Pleistocene)^[2][11]
    • †Ochotona youngi (Asia, Pliocene)^[11]
      and others.^[2][11]
  • other examples
    • †Ochotona agadzhaniani (Transcaucasia: Armenia, Pliocene)^[2]
    • †Ochotona alaica (Asia: Kyrgyzstan, Pleistocene)^[2]
    • †Ochotona (Proochotona) eximia (Moldova, Ukraine, Russia, Kazakhstan, Miocene to Pliocene)^[2]
    • †Ochotona (Proochotona) gigas (Ukraine, Pliocene)^[2]
    • †Ochotona gureevi (Transbaikalia, middle Pliocene)^[2][13]
    • †Ochotona hengduanshanensis (China, Pleistocene)^[2]
    • †Ochotona intermedia (Asia, Pliocene)^[2][11]
    • †Ochotona (Proochotona) kalfaense (Europe: Moldova, Miocene)^[2]
    • †Ochotona (Proochotona) kirgisica (Asia: Kyrgyzstan, Pliocene)^[2]
    • †Ochotona kormosi (Hungary, Pleistocene)^[2][10]
    • †Ochotona (Proochotona) kurdjukovi (Asia: Kyrgyzstan, Pliocene)^[2]
    • †Ochotona largerli (Georgia, Pleistocene)^[2]
    • †Ochotona lazari (Ukraine, Pleistocene)^[2]
    • †Ochotona mediterranensis (Turkey, Pliocene)^[2]
    • †Ochotona ozansoyi (Turkey, Miocene)^[2]
    • †Ochotona pseudopusilla (Ukraine and Russian Plain, Pleistocene)^[2][11]
    • †Ochotona spelaeus (Ukraine, late Pleistocene)^[2][16]
    • †Ochotona tedfordi (China: Yushe Basin, late Miocene)^[2][10]
    • †Ochotona cf. whartoni (Irkutsk Oblast and Yakutia, Pleistocene, see also North America)^[11]
    • †Ochotona zabiensis (southern Poland, early Pleistocene)^[2][10]
    • †Ochotona sp. (Greece: Maritsa, Pliocene)^[11]
    • †Ochotona sp. (Hungary: Ostramos, Pleistocene)^[11]
    • †Ochotona sp. (Siberia, Pleistocene)^[11]
    • †Ochotona sp. (Yakutia, Pleistocene)^[11]
• North America
  • †Ochotona gromovi (USA: Colorado, Pliocene, see also Eurasia)^[2]
  • †Ochotona spanglei (USA, late Miocene or early Pliocene)^{[2][11][15][17][18][n 2]}
  • †Ochotona tologoica (USA: Colorado, Pliocene, see also Eurasia)^[2]
  • †Ochotona whartoni (giant pika, USA, Canada, Pleistocene to early Holocene, see also Eurasia)^{[2][11][15][19][20][n 3]}
  • †Ochotona wheatleyi (USA: Alaska, Pliocene, late Pleistocene)^[2]
  • †Ochotona zazhigini (USA: Colorado, Pleistocene, see also Eurasia)^[2]
  • extinct small pikas similar to the O. pusilla group (Pleistocene)^[11][15]

Paleontologists have also described multiple forms of pika not referred to specific species (Ochotona indet.) or not certainly identified (O. cf. antiqua, O. cf. cansus, O. cf. daurica, O. cf. eximia, O. cf. gromovi, O. cf. intermedia, O. cf. koslowi, O. cf. lagrelii, O. cf. nihewanica). The status of Ochotona (Proochotona) kirgisica and O. spelaeus is uncertain.^[2]

The "pusilla" group of pikas is characterized by archaic (plesiomorphic) cheek teeth and small size.^[15]

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.^[11]
• Ochotona whartoni (giant pika) and small pikas via the Bering Land Bridge during the earliest Pleistocene.^[11]

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).^[11]

The range of Ochotona was larger in the past, with both extinct and extant species inhabiting western Europe and eastern North America, areas that are currently free of pikas. Pleistocene fossils of the extant steppe pika Ochotona pusilla currently native to Asia have been found also in many countries of Europe from the United Kingdom to Russia and from Italy to Poland, and the Asiatic extant northern pika Ochotona hyperborea in one location in the middle Pleistocene United States.^[2]

Pika Ochotona sp. fossil distribution. Extinct pikas and Ochotona indet. are red, steppe pika O. pusilla blue, northern pika O. hyperborea green, other extant pikas black.^{[2][3][n 1]}

Fossil occurrences of leporids and ochotonids and global environmental change (climate change, C₃/C₄ plants distribution).^[2]

Other genera of ochotonids (currently living only Ochotonidae) include except Ochotona (pika) extinct †Albertona, †Alloptox, †Amphilagus, †Australagomys, †Austrolagomys, †Bellatona, †Bellatonoides, †Bohlinotona, †Cuyamalagus, †Desmatolagus, †Eurolagus, †Gripholagomys, †Gymnesicolagus, †Hesperolagomys, †Heterolagus, †Kenyalagomys, †Lagopsis, †Marcuinomys, †Ochotonoides, †Ochotonoma, †Oklahomalagus, †Oreolagus, †Paludotona, †Piezodus, †Plicalagus, †Pliolagomys, †Prolagus, †Proochotona (syn. Ochotona), †Pseudobellatona, †Ptychoprolagus, †Russellagus, †Sinolagomys and †Titanomys.^[2] The earliest one is Desmatolagus (middle Eocene to Miocene, 42.5–14.8 Ma^[2]), usually included in Ochotonidae, sometimes in Leporidae or in neither ochotonid nor leporid stem-lagomorphs.^[21]

Ochotonids appeared in Asia between the late Eocene and the early Oligocene, and continued to develop along with increased distribution of C₃ grasses in previously forest dominated areas under the "climatic optimum" from the late Oligocene to middle Miocene. They thrived in Eurasia, North America and even Africa. The peak of their diversity occurred during the period from the early Miocene to middle Miocene, most of them became extinct during the transition from the Miocene to Pliocene, what was accompanied by diversity increase in the leporids. It has been proposed, that this switch between ochotonids and larger leporids was caused by linked to global cooling expansion of C₄ plants (particularly in the Poaceae) in the late Miocene, since extant pikas reveal a strong preference for C₃ plants (Asteraceae, Rosaceae and Fabaceae, many of them C₃). Replacement of large area of forest on the earth that time by open grassland first started probably in North America is called sometimes "nature's green revolution".^[2]

Notes

1. The coordinates of additional fossils not listed in the xls file attached to Ge and all paper^[2] were taken from the Paleobiology Database.^{[3][pdb 1][pdb 2][pdb 3][pdb 4][pdb 5][pdb 6][pdb 7][pdb 8][pdb 9][pdb 10][pdb 11][pdb 12][pdb 13][pdb 14][pdb 15][pdb 16][pdb 17][pdb 18][pdb 19][pdb 20][pdb 21][pdb 22][pdb 23]}
2. Ochotona spanglei in the Paleobiology Database.^{[18][pdb 24][pdb 25][pdb 26]}
3. Ochotona whartoni in the Paleobiology Database.^{[20][pdb 27][pdb 15][pdb 11][pdb 12][pdb 28][pdb 29][pdb 30]}

References

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8. "Dialects in southern Rocky Mountain pikas, Ochotona princeps (Lagomorpha)". Animal Behaviour 21: 124–137. doi:10.1016/S0003-3472(73)80050-8.
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11. 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)" (PDF). Palaeontologia Electronica (Society of Vertebrate Paleontology): 1–9. Retrieved April 13, 2014.
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16. Rekovets, Leonid (2003). "Mammoth (Mammuthus primigenius) in the periglacial faunas of Ukraine" (PDF). 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
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18. "Ochotona spanglei Shotwell 1956". The Paleobiology Database.
19. 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.
20. "Ochotona whartoni Guthrie and Matthews, Jr. 1971 (pika)". The Paleobiology Database.
21. Hordijk, Kees (2010). "Perseverance of pikas in the Miocene : interplay of climate and competition in the evolution of Spanish Ochotonidae (Lagomorpha, Mammalia)". Geologica Ultraiectina (Departement Aardwetenschappen) 333. ISBN 978-90-5744-194-3. Retrieved May 27, 2014. document type Dissertation full text

•  This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "^{article name needed}". Encyclopædia Britannica (11th ed.). Cambridge University Press.

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11. Harington, C. R. (1978). "Quaternary vertebrate faunas of Canada and Alaska and their suggested chronological sequence". Syllogeus 15. [J. Alroy/J. Alroy]
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16. Kurten, B.; Anderson, E. (1980). Pleistocene mammals of North America. pp. 1–442. [J. Alroy/J. Alroy/J. Alroy]
17. Mead, J. I.; Grady, F. (1996). "Ochotona (Lagomorpha) from late Quaternary cave deposits in eastern North America". Quaternary Research 45 (1): 93–101. doi:10.1006/qres.1996.0009. [J. Alroy/J. Alroy/J. Alroy]
18. Qiu, Z. (1987). "Neogene micromammals of China". Whyte, P., ed. Paleoenvironment of East Asia from the mid-Tertiary, Second International Conference on the Paleoenvironment of East Asia 77 (1–2): 834–848. [W. Clyde/J. Finarelli/W. Clyde]
19. Rasmussen, D. L. (1974). "New Quaternary mammal localities in the upper Clark Fork River valley, western Montana". Northwest Geology 3: 62–70. [M. Uhen/C. Peredo]
20. Sotnikova, M.V.; Dodonov, A.E.; Pen'kov, A.V. (1997). "Upper Cenozoic bio-magnetic stratigraphy of Central Asian mammalian localities". Palaeogeography, Palaeoclimatology, Palaeoecology 133: 243–258. doi:10.1016/s0031-0182(97)00078-3. [A. Turner/H. O'Regan/H. O'Regan]
21. Terzea, E. (1996). "Biochronology of the Pleistocene deposits at Betfia (Bihor, Romania)". Acta Zoologica Cracovensia 39 (1): 531–540. [A. Behrensmeyer/H. O'Regan/H. O'Regan]
22. Winkler, A. J.; Grady, F. (1990). "Ochotona (Lagomorpha) from late Quaternary cave deposits in eastern North America". Journal of Vertebrate Paleontology 10 (4). [J. Alroy/J. Alroy]
23. Additional contributors to utilized records of Paleobiology Database (authorizers supplying these records) include John Alroy, Anna Behrensmeyer, Will Clyde, Alan Turner, Mark Uhen.
24. Shotwell, J. A. (1956). "Hemphillian mammalian assemblage from Northeastern Oregon". Geological Society of America Bulletin 67: 717. doi:10.1130/0016-7606(1956)67[717:hmafno]2.0.co;2. [J. Alroy/J. Alroy]
25. Voorhies, M. R. (1990). Gustavson, T. C., ed. Bureau of Economic Geology Guidebook. [J. Alroy/J. Alroy]
26. Additional contributors to utilized records of Paleobiology Database (authorizers supplying these records) include John Alroy.
27. Guthrie, R. D.; Matthews, Jr., J. V. (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. [J. Alroy/J. Alroy]
28. Storer, J. E. (2004). "A Middle Pleistocene (late Irvingtonian) mammalian fauna from Thistle Creek, Klondike Goldfields region of Yukon Territory, Canada". Paludicola 4 (4): 137–150. [J. Alroy/J. Alroy]
29. Tedford, R. H.; Wang, X; Taylor, B. E. (2009). "Phylogenetic Systematics of the North American Fossil Caninae (Carnivora: Canidae)". Bulletin of the American Museum of Natural History 325: 325:1–218. doi:10.1206/574.1. [J. Marcot/J. Marcot]
30. Additional contributors to utilized records of Paleobiology Database (authorizers supplying these records) include John Alroy, Jonathan Marcot.

External links

• The trek of the pika, by Michael Morris, Parks Canada, Mount Revelstoke and Glacier National Parks. (includes sound file)