Transcript Lecture 23-Ungulates

“Ungulata” (various supraordinal ranks) has included:
Cetacea: whales
Artiodactyla: even-toed ungulates
Perissodactyla: odd-toed ungulates
Hyracoidea: hyraxes
Proboscidea: elephants
Sirenia: manatees & dugongs
Tubulidentata: aardvarks
Various fossil orders...
Whales & dolphins
Artiodactyls
Artiodactyls
Carnivorans
Pangolins
Perissodactyls
Bats
Solenodons
Moles
Shrews
Hedgehogs
Primates
Treeshrews
Colugos
Lagomorphs
Rodents
Xenarthrans
Golden moles
Tenrecs
Elephant shrews
Aardvarks
Dugongs & manatees
Hyraxes
Elephants
Mesaxonic
horse
tapir
rhino
“double-pulley”
astragalus in artios
limits distal limb
motion to single plane
pronghorn
pig
deer
camel
Paraxonic
Cranial appendages in ruminants
Funcions:
-enable males to carry out combat in competition for mates
-secondarily used for display, indicators of social status,
antipredator defense, secretion delivery
Cranial appendages in ruminants
bovid
True “horns” only found in bovids (Bovidae).
-unbranched and permanent
-Inner bony core, extension of frontal bone
-no parts are shed
Cranial appendages in ruminants
bovid
Single pair in all but one living bovid
(four-horned antelope, Tetracerus)
Cranial appendages in ruminants
antilocaprid
Pronghorns (found only in Antilocapridae)
-Similar bony core to bovids
-horny sheath shed annually
Cranial appendages in ruminants
cervid
True antlers only in Cervidae
-entirely bony when fully developed
-extension of frontal bone
-shed periodically (usually annually in temperate zones)
-during growth, covered with velvet (highly vascularized)
Cranial appendages in ruminants
giraffe
Giraffe “horns”
-bony processes, but not outgrowths of the frontal bone
-situated over sutures b/w frontal and parietal bones
-permanently covered with skin and hair
-present from birth in both sexes
Cranial appendages in ruminants
rhino
Rhinoceros “horns”
-non-bony
-solid mass of hardened epidermal cells formed from cluster
of long dermal papillae
-resulting fibers hair-like, but grow differently from true hairs
-not attached to underlying nasal bones
Order Perissodactyla: 3 families, 6 genera,ca 17 species
Family Equidae (horses, asses, zebras)
1 genus, ca. 8 species
Family Tapiridae (tapirs)
1 genus, 4 species
Family Rhinocerotidae (rhinos)
4 genera, 5 species.
-MESAXONIC
glutenized, keratinized fibers
Order Artiodactyla: 10 families, 80 genera, >220 species!
Suborder Suiformes
Family Suidae
-pigs
PARAXONIC
Family Tayassuidae
-peccaries
Family Hippopotamidae -hippos
Suborder Tylopoda
Family Camelidae
-camels, guanaco, llama, alpaca
Suborder Ruminantia
Infraorder Tragulina
Family Tragulidae
-chevrotain, mouse deer
Infraorder Pecora
Superfamily Giraffoidea
Family Giraffidae
-giraffes
Superfamily Cervoidea
Family Moschidae
-musk deer
Family Cervidae
-deer, elk, caribou, moose, reindeer
Family Antilocapridae -pronghorn
Superfamily Bovoidea
Family Bovidae -bison, muskox, goats, sheep, antelope, cows
Major CRANIODENTAL trends in ungulate evolution:
Omnivore/carnivore
•pointy incisors & canines
•large temporalis, coronoid
process; small angular pr.
of dentary
•cheekteeth tritubercular
or bunodont
Herbivore
•flat incisors, us. no
canines; diastema
•small temporalis, coronoid
process; large angular pr.
•cheekteeth flat for
grinding;
lophodont, selenodont,
bilophodont, etc.
Major DIGESTIVE trends in ungulate evolution:
Omnivore/carnivore
•simple, monogastric stomach
Herbivore
•complex stomach,
either foregut fermentation (digastric stomach)
or hindgut (cecal or
monogastric) fermentation
Herbivore
Carnivore
Insectivoran
Rumination
(foregut
fermentation)
Hindgut
fermentation
Cellose
digested:
60%
40-45%
Major POSTCRANIAL trends in ungulate evolution:
Omnivore/carnivore
•simple, monogastric stomach
Herbivore
•complex stomach,
either foregut fermentation (digastric stomach)
or hindgut (cecal or
monogastric) fermentation
•plantigrade
•digitigrade, unguligrade,
graviportal.
•increase SPEED!
BIOMECHANICS:
Application of mechanical principles
on living organisms.
Plantigrade
Digitigrade
Unguligrade