Characteristics: Odd-toed with hoof (ungulates) = horses, rhinos, tapirs



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Order Perissodactyla
Characteristics:

  • Odd-toed with hoof (ungulates) = horses, rhinos, tapirs

  • Weight distributed on central digits 2, 3, 4

  • 1 toe per foot = horses

  • 3 toes per foot = tapirs, rhinos

  • 1st digit absent

  • Enlarged colon with microorganisms for digestion of cellulose


Family Tapiridae – tapirs

  • Semi-aquatic, tropical forest

  • Oriental & South American rivers

  • Proboscis-like nose similar to elephant

  • Front feet = 4 toes; hind feet = 3 toes


Family Rhinocerotidae – rhinos

  • Arose in North America, later extinct

  • Africa & Asia – plains/savanna; also IndoChina = forest

  • Horn-like growth made of hair (keratin) – poaching & extinction

  • Hypsodont molars resembling greek symbol pi (π)


Family Equidae – horses

  • Arose in North America, later extinct, Spanish return with horses

  • Early horses spread into Africa (zebras & asses), Asia and Europe

  • Evolution

    • No horses, Hyracotherium, Miohippus, Mesohippus or Merychippus, Pliohippus, Equus

  • Hyracotherium also ancestor of rhinos & tapirs












Equus caballus (horse)

Order Artiodactyla
Characteristics:

  • Even-toed with ungulates = deer, pigs, antelope, etc…)

  • Trend = 2 toes or 4 toes, or 2 toes with dew hooves

  • Paraxonic feet = division of 3rd & 4th toe along symmetrical plane

  • 1st toe absent, 2nd and 5th toes absent or reduced

  • Astragalus double pulley (ankle bone) – restricts lateral movement

  • Cannon bone (allows greater jumping ability)












right front feet of a pig (Sus), hippo (Hippopotamus), elk (Cervus), and camel (Camelus)

cannon bones



Advancements:

  • Ruminant stomach (multi-chambered)

  • Horns, antlers

  • Selenodont molars


heads and antler types of representative cervids:  clockwise from lower left – Père David’s deer (Elaphurus), moose (Alces), caribou (Rangifer), white-tailed deer (Odocoileus), Chinese water deer (Hydropotes), and pudu (Pudu).  Skull is of a sika deer (Cervus)

heads, horn shapes, and sizes of selected bovids:  A – suni antelope (Neotragus), B – klipspringer (Oreotragus), C – Grant’s gazelle (Gazella); D – waterbuck (Kobus), E – hartebeest (Alcelaphus), wildebeest (Connochaetes), G – addax (Addax); and H – oryx (Oryx)



Family Tayassuidae – peccaries or javelinas

  • Arid regions of SW

  • Bunodont teeth


Family Suidae – 4 toes (pigs)
Sus scrofa (wild boar)

  • Omnivores

  • Exotic from the Old World

  • Habitat destruction

  • Long & low skull with high occipital region

  • Bunodont teeth

  • Ever-growing canines


Family Camelidae – 2 toes (camels)

  • Asia & Africa

  • guanaco, llama, alpaca, vicuna of South America


Family Antilocapridae – 2 toes (antelopes)
Antilocapra (pronghorn antelope)

  • plains of North America

  • sheds outer horn covering annually, branched horn

  • horns on both sexes

  • large white rump


Family Cervidae – (deer) – only males have antlers, except caribou
Odocoileus virginianus (white-tailed deer)

  • one main antler beam with minor branching

  • shallow lacrimal pit

  • range expansion

  • human-deer conflicts

  • most popular big game animal in U.S.

  • science-based management?


Odocoileus hemionus (mule deer)

  • western U.S.

  • black tip on tail

  • large, mule-like ears (2/3 to ¾ length of head)

  • antlers branch into 2 equal parts

  • deep lacrimal pit (~23 mm deep)


Cervus elaphus (elk)

  • Rocky Mts. Although once widespread into the plains

  • Large yellowish rump patch

  • Dark brown neck, breast, legs

  • One of largest North American deer

  • Bugling

  • Same as red deer in Europe



Alces alces (moose)

  • Primarily boreal forest biome

  • Largest deer

  • Broad, over-hanging muzzle

  • Massive, dished (palmate) antlers (max. spread ~2m)

  • Heavy mane & pendulant flap


Rangifer (caribou)

  • Tundra (barren ground caribou) and boreal forest (woodland caribou) biomes

  • Both sexes have antlers

  • Varied coloration; brown-gray above, whitish belly, inner legs & rump

  • Clicking noise when walking = tendon slipping over the bone

  • Seasonal migration


Family Bovidae – cattle, sheep, goats

  • Entire horn (sheath & core) never shed and usually grow throughout life; also unbranched horns


Bison bison (bison)


Ovis canadensis (bighorn sheep)

  • Rocky Mts.







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