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Lagomorpha. pikas, rabbits, and hares. Fast Facts. Today consist of 2 families, ~13 genera, ~80 species Ochotonidae - pikas Leporidae - jackrabbits & hares and rabbits Prolagidae - Mediterranean giant pikas (extinct) Earliest fossil- 55 million years ago in Mongolia
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Lagomorpha pikas, rabbits, and hares
Fast Facts • Today consist of 2 families, ~13 genera, ~80 species • Ochotonidae- pikas • Leporidae- jackrabbits & hares and rabbits • Prolagidae- Mediterranean giant pikas (extinct) • Earliest fossil- 55 million years ago in Mongolia • Families much more diverse in the Tertiary period than today
Fast Facts • Herbivores • Peg like teeth • Terrestrial • Found on all continents except Antarctica • Exotic species in Australia and New Zealand • Similar adaptations to Rodentia • Possible SuperorderGlires???
Leporididae vs. Ochotonidae Leporididae • Large ears • Elongated hind limbs • “cotton ball” tails • Fenestrated maxilla • Arctic, deserts, tropics, forest Ochotonidae • Small ears • Short limbs • No tails • Notched incisors • Talus slopes or steppe areas
Leporids: Rabbits vs. Hares Rabbits • Well-constructed, fur lined nests • Altricial young • Interparietal bone in skull • 42 chromosomes Hares • Shallow depressions, “forms” • Precocial young • NO interparietal bone • 48 chromosomes
Pika diversity by habitat Smith, A. (2008). The World of Pikas. In Lagomorph biology evolution, ecology, and conservation. Ed. Alves, P et. al. Springer: New York
Reproduction in Leporids • Induced ovulation • Egg is released shortly after copulation • Postpartum estrus • Gestation period trade off • Higher latitudes have shorter gestation periods to produce more young in favorable weather, and larger litter size • longer gestation in tropical species are born more fully developed and able to avoid predators Chapman, J. (1984). Latitude and Gestation Period in New World Rabbits. The American Naturalist 124(3): 442-445
Coprophagy: Adaption to low quality forage • Ingestion of feces (hard & soft) • Quickly excrete poorly digestible large particles (hard), retain fine particles for excretion and re-ingestion (soft) • Very sophisticated digestive system Hirakawa, H. (2001). Coprophagy in leporids and other mammalian herbivores. Mammalian Review 31:61-80
Pika and hay making: WHY? • Storing food for winter?? • Not enough food • Don’t eat all that is stored • Haypile size have no relation to mortality • Conclusions: • Enough food for 8 months • Need large piles because only 25% of what is stored is available • Store food to survive shortages • Secondary use: bedding Biomass of haypile throughout the year Dearing, M.D. (1997). The Function of Haypiles of Pika. Journal of Mammalogy 78(4): 1156-1163
Pika and hay making: foraging selection • Observed species available and species chose based on diversity and abundance • Selective in vegetation for making hay • Chose plants rich in secondary compounds (tannins) • Reject evergreens • Conclusions: • Eat what is most available in summer • store what is not edible in summer for winter • do not store what will be available in winter Gliwicz, J., S. Pagacz, J. Witczuk. (2006). Strategy of Food Plant Selection in the Siberian Northern Pika. Arctic, Antarctic, and Alpine Research 38(1): 54-59
European Rabbits in Australia • Brought to Australia by Europeans as a game species to be hunted • Degrade the land, reduce native vegetation, and may cause extinction of native mammals • Control Methods • Biological control (virus) • Hunting and trapping • Rabbit-proof fence • Poisoning http://www.environment.gov.au/biodiversity/invasive/publications/pubs/rabbit.pdf
Metapopulations in Pika • Remain close to the location they were born • Dispersal can be difficult • Survival of one patch is highly dependent on the number of neighboring patches • Need to learn what causes patches to be recolonized or to go extinct to ensure the future of the pika Smith, A. (2008). The World of Pikas. In Lagomorph biology evolution, ecology, and conservation. Ed. Alves, P et. al. Springer: New York
MainPoints • Diversity within the order • Pika, rabbits, and hares • Reproduction • Induced ovulation, gestation periods • Foraging Adaptations • Hay making and coprophagy • Management Issues • too many, metapopulation dynamics
Works Cited Chapman, J. (1984). Latitude and Gestation Period in New World Rabbits. The American Naturalist 124(3): 442-445 Chapman, J. & J.E.C. Flux. (2008) Introduction to the Lagomorpha. InLagomorph biology evolution, ecology, and conservation. Ed. Alves, P et. al. Springer: New York Dearing, M.D. (1997). The Function of Haypiles of Pika. Journal of Mammalogy 78(4): 1156-1163 Gliwicz, J., S. Pagacz, J. Witczuk. (2006). Strategy of Food Plant Selection in the Siberian Northern Pika. Arctic, Antarctic, and Alpine Research 38(1): 54-59 Hirakawa, H. (2001). Coprophagy in leporids and other mammalian herbivores. Mammalian Review 31:61-80 Smith, A. (2008). The World of Pikas. In Lagomorph biology evolution, ecology, and conservation. Ed. Alves, P et. al. Springer: New York http://www.environment.gov.au/biodiversity/invasive/publications/pubs/rabbit.pdf Picture Credits • www.cryptomundo.com, • www.dgsgardening.btinternet.co.uk, • northwestnaturalmoments.blogspot.com • westerncascades.com • environmentyukon.gov.yk.ca, • thehuntinglife.com • http://animaldiversity.ummz.umich.edu/site/accounts/classification/Mammalia.html#Mammalia%23 • wild-facts.com