Mammalogy Exam 2 Study Guide
EXAM 1 ORDERS/FAMILIES
Order Rodentia has a cosmopolitan distribution, 5 suborders (diagnosed by position of masseter muscles relative to infraorbital foramen), and has diagnostic characteristic of a single pair of ever growing incisors. Includes families Aplodontiidae, Sciuridae, Castoridae, Geomyidae, Heteromyidae, Erethizontidae, Echimyidae, Cricetidae, Muridae.
Family Aplodontiidae is mountain beavers (single species), distribution is pacific northwest, has many ancestral features and prefers riparian habitats.
Family Sciuridae is squirrels/chipmunks/marmots/prairie dogs, diurnal herbivores, skull arched in profile, masseter on anterior zygomatic plate, locomotion and thermoregulation varies. Distribution is cosmopolitan.
Family Castoridae is beavers (two species), semiaquatic, highly insulative fur, ecological engineers. Distribution is north america and Eurasia. Diagnostic characteristic is deep zygomasseteric groove for masseter.
Family Geomyidae is gophers, fossorial, external fur-lined cheek pouches, small pinnae, fimbration between toes. Distribution is North America.
Family Heteromyidae is kangaroo rats and allies, many have desert adaptations like enlarged auditory bullae, elongated hind limbs. Nocturnal, herbivorous or granivorous, foot drumming and seismic communication. Distribution is New World.
Family Erethizontidae is New World Porcupines, barbed quills on much of body, robust skull, eat cambium layer in winter. Distribution is New World.
Family Echimyidae is nutria (tribe myocastorini), resemble beavers with rat tails, large, capable swimmers, native to S Amer but introduced to N Amer too.
Family Cricetidae is second largest mammal family, cosmopolitan distribution, new world mice and rats.
Family Muridae is largest mammal family, cosmopolitan, old world mice and rats, medial masseter passes through dorsal infraorbital foramen.
Order Lagomorpha is nearly cosmopolitan, 2 families (only need to know 1), dramatic cycles in north. Diagnostic characteristic is single pair or upper and lower incisors and peg like 2nd incisors.
Family Leporidae is rabbits and hares, have skull fenestration, cursorial adaptations, hypsodont teeth, is nearly cosmopolitan.
Order Proboscidea are elephants, 3 species, graviportal with columnar limbs, originate in Africa but current distribution is Africa and India, incisors become tusk-like, enlarged skull and reduced neck, elongated probiscus/trunk, anterior replacement of cheek teeth (conveyer belt, one tooth at a time), largest living terrestrial mammals, digitigrade, large ears, highly social.
Order Hyracoidea are hyraxes, 5 species, distribution is Africa and Middle East, incisors ever growing, feet mesaxonic (weight axis on 3rd/middle toe), diastema present, rabbit-sized, deep mandible, herbivores, scansorial, diurnal, polygynous.
Order Sirenia are manatees/dugongs/sea cows, 4 species, diagnostic characteristic is they are the only herbivorous marine/aquatic mammal, distribution is tropical ocean/coast worldwide, ballasts help hold position in water, valvular nostrils, nearly hairless, thick dentary, large middle ears, cheek teeth like slow conveyer belt, tail horizontal fluke, slow moving, little body fat (is why in tropics), long lived.
EXAM 2 CONTENT
Order Eulipotyphla: cosmopolitan/worldwide, moles, shrews, and shrew-moles, primarily insectivorous, most characteristics are ancestral, no key/diagnostic characteristics, are pendactyl (5 toes) and plantigrade, long pointed snouts, pinnae small or absent, small to medium size, include families Soricidae and Talpidae.
Family Soricidae: cosmopolitan, shrews, small and inconspicuous, eyes and pinnae small, snout long and slim, goethite (rust red) teeth, fairly diagnostic for shrews is single large hooked upper incisor, some venomous, high metabolic rates, active day and night.
Family Talpidae: Northern Hemisphere, moles and shrew-moles, eyes small, pinnae absent, snout elongate, lustrous pelage, forelimbs can go forward/backward and up/down but not side-to-side, limbs and phalanges short and stout, long claws, Eimer’s organ let detect electrical fields.
Feeding Types: can be primitive/basal insectivores, specialized insectivore, omnivores, grazing and browsing herbivores or gnawing herbivores, carnivores, fish and squid specialists, plankton specialists, mollusk specialist, fruit specialists, or nectar specialists. Their skulls can be highly specialized for their diet. Carnivores have enlargement of canines and lack of mini cheek-teeth. Herbivores have diastema, loss of canines, reduction of incisors, many check-teeth, high cusp cheek-teeth for accidental dirt/branches, either graze (grass) or browse (brush), are foregut or hindgut fermenters. Omnivores have rounded cheek-teeth with canines.
Foregut vs Hindgut Fermenters: plant eaters have complex digestive systems since need to break down defensive compounds and cellulose, can be ruminant/foregut fermenters or nonruminant/hindgut fermenters. Ruminants have a 4-chambered stomach, can chew their cud, and get more energy from food but digestion takes a long time. Are mainly cervids and bovids. Nonruminants have simple stomachs but enlarged cecums and get less energy from food but digestion is very fast. Are mainly equids.
Net food energy involves search energy/time, pursuit energy/time, handling energy/time, and eating energy/time.
Order Monotremata: distribution is Australia, egg-laying, includes echidnas and platypus, have both many ancestral characteristics and many derived characteristics, teeth when babies but edentate when adults, rostrum have receptors, long lactation periods, lack nipples, have cloaca, abdominal testes is ancestral trait.
Monotremes vs Metatherians vs Eutherians: Monotremes are oviparous (egg-laying), gestation is actually incubation, and have long lactation periods. Metatherians are viviparous (give birth) with short gestations and long lactation periods. Eutherians are viviparous with long gestations and short lactation periods. Main idea is metatherians spend more energy in lactation while eutherians spend more energy in gestation.
Metatherians: 3 South American orders and 4 Australian orders, short gestation with young born tiny and poorly developed, newborns crawl to marsupium and attach to nipple, not all have pouches, small narrow braincase, can’t specialize as well as eutherians due to short gestation.
Order Didelphimoria: includes family Didelphidae (only one family so basically same as order), distribution is Americas, includes opossums, tail usually prehensile, braincase long and narrow, includes Virginia opossum.
Order Paucituberculata: South American distribution, shrew-opossums, no marsupium, lower incisors procumbent.
Order Microbiotheria: South American distribution, single species Monito del monte, may hibernate, relic of Australian/Antarctic radiation, in southern Andes mountains.
Order Dasyuromorphia: Australian distribution, represent carnivore-like, includes Tasmanian devils, thylacine, numbat, and other small carnivores.
Order Peramelemorphia: Australian distribution, represents rodent-like and small herbivore-like, includes bandicoots and bilbies, hindfeet modified for cursorial locomotion.
Order Notoryctemorphia: Australian distribution, represent fossorial metatherians, includes 2 species of marsupial moles, convergent evolution with moles (eyes vestigial, ears lack pinnae, cornified skin on nose, enlarged claws for digging, marsupium opens posteriorly), swim through soil with pathway collapsing behind them.
Order Diprotodontia: Australian distribution, represent many niches but primarily herbivores, include kangaroos, wombats, koalas, possums, gliders, etc., includes family Macropodidae.
Family Macropodidae: Australia, small to large, huge family, much convergence with ungulates (browse and graze, specialized digestive system for microbial fermentation, enlarged astralagus that helps ankle), marsupium opens anteriorly, broad diastema, specialized for jumping, includes kangaroos, euros, and wallabies, digits 2 and 3 small and syndactylous (fused, often in same skin sheath, saltatorial/cursorial, hindgut fermentation with enlarged cecum, tail can act as tripod or balance.
Order Chiroptera: bats, second largest mammalian order, key characteristic is true flight (volant), distribution temperate to tropical, echolocation in most species, many food niches, patagium let fly, can have highly developed and differing uropatagium, ears, and noses, fly slow but maneuverable, unequal pressure above and below wing generate lift, low aspect ratio wings (ratio of wing span to wing chord small), low wing loading (ratio of body weight to wing area small), few can hover. Echolocation is used to see and find prey, often comes with specialized ears (can have tragus too) or nose, sound made in larynx and either emitted from nose or mouth, tragus serves as antenna for brain to hear during echolocation, frequency is how often they yell, amplitude is loudness of yell, use low frequency with high amplitude for wide search and high frequency with low amplitude when get closer.
Family Pteropodidae: non-echolocating bats, fruit bats, called old world but are actually everywhere but North America, largest bats, foxlike rostrum and large eyes, lack tragus, typically roost in trees.
Family Mormoopidae: new world distribution, ghost-faced bats, key characteristic is oral emitter with mustaches, ears moderately large with tragus, specialized elbow joint that is extended/flexed at rest.
Family Phyllostomidae: neotropical distribution, leaf-nosed bats, nasal emitters, most diverse bat family with many food niches and diverse morphology, includes insectivores, carnivores, frugivores, nectivores, sanguinivores (vampire bats).
Family Molossidae: simple faced oral emitters, free-tailed bats, mostly cosmopolitan, big pinnae, thick lips, high speed and endurance, fly high, insectivores, fly long distances to forage, well developed quadrupedal locomotion.
Family Vespertilionidae: evening/vesper bats with simple faces, nearly worldwide distribution, mostly insectivorous, small.
Reproduction: features of mammals are mammary glands, milk, suckling, diphyodont dentition, mainly viviparity, close mother-young bond, testes descend into external pouch for most mammals (not in monotremes and marine), may have baculum, monestrous is single estrous cycle per year, polyestrous is multiple estrous cycles per year, females have higher reproduction cost, maternal investment equal per kg in all mammals but in different times/purposes (mono and meta put most energy in lactation, eu put most in gestation, placentas have varying degrees of contact based on interaction and nutrition exchange, stages of metatherian lactation are mammogenesis (preparation of mammary glands), early lactogenesis (young attached to teat), and late lactogenesis (young detached from teat), metatherians have milk composition changes during lactation while eutherians have fairly constant composition throughout lactation, females can delay child birth with diapause by using delayed fertilization by storing sperm, delay implantation of blastocyst, or delay development after implantation, can have helpless altricial or functional precocial (locomotion key factor in distinctions), can disperse to avoid inbreeding (mainly males leave).
Order Carnivora: worldwide distribution, c-shaped mandibular fossa is key, two major clades of feliformia and caniformia, mostly predaceous, acute smell, cursorial mainly (wrist adaptations help run), 4th upper premolar and 1st lower molar are carnassials, diverse pelage, some baculum, anal scent glands, most digitigrade, large canines.
Suborder Feliformia: worldwide,includes felidae and herpestidae.
Family Felidae: worldwide, typically strict carnivores, shear-like sharper carnassials than canids, teeth reduced with single pair of molars, digitigrade, claws recurved and retractile, spotted/striped common, small to large, stealth then quick speed burst, many solitary, excellent senses, some nocturnal with tapetum lucidum.
Family Herpestidae: old world except introductions, mongooses and meercats, small long bodied, large auditory bullae, anal glands, some complex social.
Suborder Caniformia: worldwide, more omnivorous than felids but still mainly carvirorous, includes bears, dogs, skunks, pinnipeds, etc.
Family Canidae: worldwide, large nasal chamber with excellent sense of smell, highly cursorial, robust canines, digitigrade, blunt nonretractable claws, long limbs, carnassials present, molars for crushing, small to large, dogs and foxes.
Family Ursidae: worldwide, large size, plantigrade, short tails, more omnivorous, long rostrum, nonretractable claws, teeth for crushing, great smell sense, may “hibernate”.
Pinnipeds (families Odobenidae, Otariidae, Phocidae): temperate to polar and cold water distribution, highly adapted to marine lifestyle but are actually aquatic, include seals, sea lions, and walrus, large, blubbery, pinnae small or absent, abdominal genitalia, forelimbs flipper-like, fusiform, large eyes, diving and swimming advanced.
Family Mephitidae: Americas/west hemisphere, skunks, key is anal glands that spray noxious odor/liquid, opportunistic eaters, black and white coloration, good diggers, solitary, nocturnal.
Family Procyonidae: new world distribution, plantigrade, omnivores, tail long, dexterous forefeet in some, nonretractable or semi retractable claws, raccoons, ringtails, kinkajous, and coatis.
Family Mustelidae: worldwide, strongest c-shaped mandibular of caniforms, weasel-like, carnassials blade-like, short limbs with elongate bodies, long braincase, short rostrum, anal glands, include otters, minks, weasels, badgers, induced ovulation common with delayed implantation common.
Order Pholidota: tropical to subtropical Africa and SE Asia, pangolins, “scales” made of keratin so technically hair, tongue veriform (worm-like), conical skull, edentate, mostly myrmecophagy.
Order Cingulata: American/New World distribution, armadillos, originate from Xenarthrans (extra articulations on lumbar vertebrae, gives rigidity to allow carapace armor), protective bony armor from agglutinated hair/keratin.
Family Dasypodidae: southern US to Argentina distribution, 9 species, long-nosed armadillos, homodont dentition, opportunistic insectivores, elongate skull, limbs for digging, one species in US is 9-banded and has embryonic diapause and 4 quadruplets.
Order Pilosa: central to south American distribution, sloths and anteaters, some myrmecophagy, originate from Xenarthrans (extra articulations on lumbar vertebrae, gives rigidity to help upside-down back), sloths folivorous foregut fermenters but no 4-chambered stomach, sloths suspensorial (hang upside-down in trees).
Order Perissodactyla: worldwide, key characteristic is mesaxonic axis of symmetry through middle digit, odd-toes ungulates, include horses, tapirs, and rhinos, hindgut fermenters, large cecum, elongate rostrums, molariform cheek teeth (variation in molars) that have large complete occlusal surfaces, herbivorous, less diverse than in past times, mainly browsers.
Family Equiidae: worldwide from human spread, horses, highly cursorial, skull large and thick, teeth hypsodont (high crowned, last while eat abrasive food), only digit 3 bears weight, most highly social, fission-fusion social system (groups increase and decrease in size throughout year).
Order Cetartiodactyla: includes artiodactyla and cetacea.
Suborder Artiodactyla: worldwide, ruminants with multichambered stomachs, even-toed ungulates, diagnostic is paraxonic with plane of symmetry through/between digits 3 and 4, slow digestion but high gained energy, cannon bone (fused 3 and 4 metapodials) in some families, astragalus with double-trochlea restricts lateral movement, limbs elongate and slim, limbs have springing ligaments.
Family Suidae: worldwide from human spread, includes old world pigs, opportunistic, long skull, large tusk-like canines in some, thick bodied, typically omnivorous, bunodont molars (rounded cusp)
Family Tayassuidae: tropic forests to deserts of New World, peccaries/javelinas, interlocking upper and lower canines, plant leaning omnivores, highly social, cursorial.
Family Antilocapra: entirely north American fossil record, north American distribution, single species of pronghorn, highly cursorial, pseudohorns on both sexes, cheek teeth high crowned.
Family Cervidae: worldwide distribution, true deer, males have antlers that shed yearly, mainly browsers, if migrate do it by elevation.
Family Bovidae: worldwide distribution, large family, horns in both sexes, mainly grazers, hypsodont (high crowned) teeth, primarily two-toed, includes ecological engineer bison, ulna reduced and fused with radius.
Suborder Cetacea: all oceans distribution, key is marine carnivores (though some omnivores), fully adapted to aquatic lifestyle, complex social behavior, all are CITES-listed, fusiform body, thick blubber, abdominal testes and enclosed teats, laminar flow around body, deep diving adaptations (like ribs that don’t connect to sternum, elastic collapsible lungs, non-vascular air spaces large), sub-dermal springs store and release energy.
Parvorder Mysticeti: all oceans distribution, baleen whales, 3 feeding modes (graze near surface (right whales), rorqual/lunge feeding (humpback), scoop/suction feeding (gray)), can’t echolocate (song different from echolocation).
Parvorder Odontoceti: all oceans and some rivers distribution, toothed whales, porpoises, dolphins, homodont teeth, use echolocation and may stun acoustically, echolocation works since sound faster and further in water, different from bats since noise originate from phonic lips near blow hole (not in larynx), increase and reverberate through melon, and return through lower jaw to ear bone.
Family Delphinidae: all oceans and some rivers, dolphin is not same as porpoise, smart, small to large, color variation, highly gregarious and social, rapid swimmers. river dolphins evolved convergently in separate places/origins.
Order Macroscelidea: African distribution, elephant “shrews” or sengis, long mobile snout, long slender legs, cursorial, foot drumming, highly precocial young, large eyes and ears, largely insectivorous.
Order Afrosoricida: African distribution, are tenrecs, “otter shrews” and golden “moles”, primarily insectivorous, retain many ancestral characteristics, are African version of moles and shews, many fossorial adaptations.
Order Tubulidentata: African distribution, single species or aardvark, poster child for myrmecophagy, powerful digger, elongate skull, long protrusible tongue, vestigial tube-like cheek teeth that are rootless, good nose, make burrows that other species often use, symbiotic with cucurbit plant.
Order Scandentia: Asian distribution, tree “shrews”, absentee parental care, squirrel-like, opportunistic but mainly fruit eaters, lower incisors form tooth comb, upper incisors caniniform, prominent hole in zygoma.
Order Dermoptera: Asian distribution, are “flying lemurs” or colugos, have gliding membrane up to fingers/toes, key diagnostic is only order where all are glissant, cecal fermenters, large eyes.
Convergent fossorial adaptations: eyes vestigial, ears lack pinnae, cornified skin on nose, enlarged claws for digging, some are order Notoryctidae (metatherian), Bathyergidae, Chrysochloridae (Afrosoricida), Geomyidae, Cricetidae, etc.
Vocabulary
Pendactyl = 5-toed
Plantigrade = walk on soles of feet
Zalambdodent = V-shaped tooth cusp pattern
Goethite = rust-red color
Frugivory = eat fruit
Nectarivory = eat nectar and/or pollen
Piscivory = eat fish
Mymecophagy = eat ants and termites
Folivory = eat leaves/stem/bud
Sanguinivory = eat blood
Filter feeder = eat krill
Granivory = eat seeds
Gummivory = eat resins, saps, gums
Mycophagy = eat fungi
Coprophagy = eat their poop
Edentate = no teeth
Lustrous = lies in any direction
Graze = eat grass
Browse = eat brush, shrubs, etc
Procumbent = incisors stick out forward
Syndactylous = fused, often in same skin sheath
Cambar = wing bendiness
Calcar = bone spur that comes off of bat ankle, anchors uropatagium
Tragus = bat ear projection commonly for echolocation
Parturition = birth or egg laying
Diapause = delay birth of young by either delay fertilization, delay implantation, or delay development
Dispersal = permanent leaving of natal territory/location
Molariform teeth = variation in molars
Hypsodont teeth = high crowned teeth, let eat abrasive foods and last longer
Bunodont teeth = rounded cusp, reflect omnivory
Paraxonic = plant of symmetry through/between digits 3 and 4
Mesaxonic = plane of symmetry through middle digit
Suspensorial = hang upside-down in trees
Veriform = worm-like
Digitigrade = walk on toes, like felids/cats
Plantigrade = walk on soles, like bears/ursidae
Oviparous - egg laying.
Viviparous - live bearing.
Anapsid - no temporal opening, amphibians/turtles.
Diapsid - two temporal openings, reptiles/dinos/birds.
Synapsid - one temporal opening, mammals.
Fossorial - live primarily underground.
Subterranean - live entirely underground.
Scansorial - rock dwelling.
Arboreal - tree dwelling.
Semi-aquatic - amphibious, often move between land and water, adapted to both land and water, example is beavers.
Aquatic - most adept in water but do land (like seals).
Marine - entirely in water.
Richochetal - jump/move in zig zag.
Granivory - herbivory type where only ear grains/seeds.
Saltitorial - jump/move in straight line.
Cursorial - run locomotion.
Ambulatory - walk.
Graviportal - long columnar legs movement.
Brachiation - use forelimbs to move through environment.
Plantigrade - move on soles of feet.
Digitigrade - move on digits.
Unguligrade - move on hooves.
Geophyte - eat underground, like naked mole rats and tubers.