Lab 9 Flashcards
Pelage
Entire covering of hair
Mammals are most easily identified by the presence of
Hair
Integumentary glands
Sweat glands
Sebaceous glands
Mammary glands
Sweat glands
Aid in thermoregulation by transporting water from skin to surface
Sebaceous glands
Produce oily substances released into hair follicles
Oils condition the hair and help maintain properties of the pelage like water resistance
Mammary glands
A defining characteristic of mammals, mammary glands are likely modified sweat glands
Pelage
Guard hair
Under hair
Vibrissae
Guard hair
The outer covering of the coat made up of longer, straight stiffer hairs with a smooth appearance
Protect the skin from water and sunlight and may be raised as a part of threat display
Under hair
Shorter and lacking in stiffness, under hairs are wavy and more numerous than guard hairs, under hair functions as insulation
Vibrissae
Whiskers
Serve as tactile sensory function
Cryptic coloration includes
Camouflage
Disruptive coloration
Countershading
Seasonal coloration
Mammalian head ornamentation
True horns
Pronghorns
Antlers
Ossicones
Rhinoceros horn
True horns
Unbranched and permanent, true horns are composed of a bony process with a keratinized covering or sheath
May be present on both sexes or only in males
Display seasonal growth rings
Pronghorns
Shed annually
Found in both males and females
Antlers
Antler vary in shape but all are highly branched and composed of bone with no keratinized sheath
Shed annually and covered with velvet (highly vascularized skin)
Typically only seen in males, except in caribous
Ossicones
Not true horns
Giraffe horns that are permanent, unbranched bony processes of the skull covered by skin
Rhinoceros horn
Composed of keratin with no bony core
Mammalians are grouped into
Prototheria
Theria (further branched into Metatheria and Eutheria)
Prototheria order
Order Monotremata
Order Monotremata
Platypus and Echidnas
Toothless and elongate jaw
Platypus with dorsoventrally flattened bill and tail
Echidnas with long tubular jaw and reduced tail
Platypus with shiny smooth pelage
Electroreceptors on leathery bills
Theria-Metatheria
Orders
Order Didelphimorphia
Order Diprotodontia
Order Didelphimorphia
Opossums
Plantigrade feet
Prehensile tail and opposable digit on their hind feet to aid in climbing
Marsupium
Fewer guard hairs
Tail long and scaled
Long snout
Prominent sagittal crest
Order Diprotodontia
Koala Wombats and Kangaroos
Two incisors of the lower jaw are procumbent (project forward)
Presence of diastema
Lack canine teeth
Relatively small braincase
Dorsal edge of the zygomatic arch (cheekbone) nearly as high as the top of the braincase
Order Afrosoricida
Tenrecs and Golden Moles
Convergent with true moles
Smooth shiny pelage
Reduced eyes and ears
Large broad claws
Short limbs
Short tail
Order Macroscelidea
Elephant shrews
Long proboscis-like snout
Large vibrissae and eyes
Long legs and hind feet
Long tails lacking fur
Order Tubulidentata
Aardvarks
Reduced dentition of simple peg-like teeth
Long snout
Reduced pelage
Large ears
Pig-like snout
Large claws
Thick tail
Order Hyracoidea
Hyraxes
Stout-bodied
Feet with thick pads
Hoof-like claws
Numerous vibrissae along entire body
Small rounded ears
reduced tail
Order Sirenia
Dugong and Manatees
Heavy skull with no incisors or canines
Tip of upper and lower jaws are laterally compressed into a flange for attachment of muscular lips
Orbits nearly closed
Large nasal opening
Order Proboscidea
Elephants
Large skull with prominent nasal opening
Upper incisors modified as pair of tusks
Luck canines
Lower jaw tip flanged for attachment of large tip muscles
Order Pilosa
Sloths and Anteaters
Xenarhrous processes (extra processes of lumbar vertebrae create)
Anteater with elongate toothless snout
Sloth with short snout and simplified/reduced teeth
Both with elongate claws of the fore feet
Order Cingulata
Armadillos
Armored
Narrow snout with reduced peg-like teeth
Robust spade-shaped claws
Order Rodentia
Rodents
Ever-growing incisors of the upper and lower jaw
Large diastema
Lack canines
Broad flattened area in front of orbit along the side of the rostrum/snout for jaw muscle attachment
Tail lacks fur
Order Lagomorpha
Rabbits, Hares and Pikas
Area in front of orbit with lace-like bone and numerous fenestrations
Double upper incisors
Rabbits and hairs with large long ears, short tail and large hind limbs
Pikas with rounded ears, reduced, lack saltatory adaptations of rabbits/hares
Order Scandentia
Tree shrews
Pointed snout
Large rounded ears
Somewhat plumose tail
Counter shaded pelage
Order Dermoptera
Flying lemurs or Colugos
Patagium of skin between neck/forelimb/hindlimb and tail
Eyes face forward
Long thin limbs
Lower incisors form a tooth-comb for grooming
Order Primates
Lemurs, Monkeys, Apes
Humans
Eyes facing forward
Rostrum reduced in monkeys, apes and humans
Brow ridge above the eyes
Cranium large and domed
Claws replaced by nails
Most with opposable thumbs
Order Eulipotyphla
Hedgehogs, Moles, and Shrews
Pointed snout
Moles with educed extremities and very robust claws
Hedgehogs with spines
Shrews mouse-like but with pointy nses
Order Chiroptera
Bats
Distinctive wing skeleton formed b elongation of fingers
Thin leathery patagium formed between digits
Reduced hind limbs
Large ears
Order Artiodactyla
Pigs Hippos Camels Deer Giraffe Antelopes Cattle
Most with complete orbital bar (orbit separated from temporal fenestra) most with large diastema
Many with head ornamentation
Reduced upper incisors
Sexual dimorphism is common
Order Cetacea
Whales
Homodonty or tooth loss
Baleen, replacing teeth in some
Reduction of zygopophyses
Loss of hind limb
Front limb modified into flipper
Order Perrisodactyla
Odd-toed Ungulates
Horses
Rhinos
Tapirs
Upper incisors present
Diastema in upper and lower jaws
Elongate head shape
Lower jaw with deep mandible
Order Carnivora
Dog-like forms
Bear Raccoon Weasel Skunk Seal Sealions and Walruses
Cat like forms
Civets Mongooses Meerkats and Hyenas
Large canine teeth
Sectorial cheek teeth
Large sagittal crest on top of skull
Long sharp claws
Family Mustelidae (weasel)
Species
Martes americana
Mustela nivalis
Gulo gulo
Taxidea taxus
Lontra canadensis
Martes americana
American marten
Elongate body
Relatively large ears
Face paler than body
Bushy tail
Mustela nivalis
Least weasel
Elongate body
small
small tail (not bushy)
Fur countershaded or cryptic in winter
Gulo gulo
Wolverine
Large
Not as elongate
Longer limbers
Bushy tail
Back lighter color with darker legs
Taxidea taxus
American badger
Body wide and held close to ground
Contrasting facial markings
Short tail
Lontra canadensis
Northern river otter
Smooth shiny pelage
Elongate body and neck
Reduced external ears
Thick muscular tail
Numerous vibrissae around mouth
Order Pholidota
Pangolins
Body entirely covered in epidermal scales
Toothless elongate snout
Large claws for digging
Arboreal forms with prehensile tails
