Back to the Main Page

Back to the Classes Page

Laboratory 2 Laboratory 5 Laboratory 8
Laboratory 3 Laboratory 6 Laboratory 9
Laboratory 4 Laboratory 7 Laboratory 10

To see phylogenetic pathways leading to contemporary Class Mammalia start HERE

To examine leading hypotheses of phylogenetic relationships among Mammalia go H ERE

Laboratory 2: ORDER CARNIVORA --- Family Mustelidae

Familia Mustelidae Swainson, 1835 (24 genera) Species Accounts Small to medium size (11-150 cm). Short limbs, digitigrade, planti-digitigrade, rarely plantigrade, 5 digits with non-retractable claws; sometimes web between digits (aquatic forms). Well developed anal glands. Well developed crests on skulls of large forms. Teeth: i3/2-3 (2 in sea otter); c1/1; p 2-4/2-4; m1/1-2 = 28-38. Well developed canines. Os penispresent.Worldwide, except most Antarctic isl., Australia, s. Pacific isl., Madagascar. Mostly terrestrial, also semi-arboreal, semi-aquatic and aquatic forms. Most solitary, some in family groups, several species (sea otters) social. Nests in dens. Most are nocturnal.

Key 1:

Key 2:

Species Accounts
Name Habitat Food Pregnancy Litter Notes
Mustela nivalis forested areas small rodents 35-37 ds, no delayed implantation 3-10 young smallest carnivore; does not change color in winter
Mustela erminea open tundra to deep forests small rodents, birds, frogs, insects 9-10 months with delayed implantation; 6 wk. without 3-18 young
Mustela frenata open brushy, grassy areas; agricultural areas small mammals delayed implantation 3-9 young
Mustela vison riparian habitats, dense vegetation small mammals, fish, frogs, invertebrates variable delayed implantation
Mustela nigripes short and mid-grass prairies prairie dogs no or short (7-8 ds) delayed implantation 3-4 young endangered
Martes americana coniferous forests birds, invertebrates, carrion, rodents; esp. pine squirrels; fruits delayed implantation 1-4 young lactation ca. 60 ds
Martes pennanti dense forests small-to-medium mammals, birds, carrion delayed implantation
Gulo gulo tundra-taiga; forests, mountains carrion, birds, ungulates 8-9 months with delayed implantation 1-5 young lactation ca 90 ds
Taxidea taxus dry, open areas ground squirrels, other mammals delayed implantation 1-5 young may go into torpor
Mephitis mephitis woodlands, grasslands to deserts (prefers highways) omnivorous short delayed implantation 4-5 young (too) well developed anal glands
Spilogale gracilis brushy, rocky,dry wooded areas omnivorous delayed implantation 6 young
Lutra canadensis aquatic fish, frogs, invertebrates, other mammals 10-13 months with delayed implantation 2-3 young Nostrils and ear canals can be closed while under water; even length fur on tail and body; no anal glands

Laboratory 3:

ORDER CARNIVORA -- Family Canidae & Family Felidae

Familia Canidae Gray, 1821

(11 genera)Species Accounts

Body length 40-160 cm; tail 11-55 cm; Digitigrade; front legs 5 digits (exc.1 sp); hind legs 4 digits, non-retractable claws. Uniform coloration, sometimes with seasonal change in color. Teeth: 3/3-4;1/1; 4/4; 1-4/2-5 = 38-50. Worldwide distribution except Antarctica and some oceanic islands. Mostly open landscapes. Terrestrial. Most can run very fast (up to 65 km/h in coyote); some excavate very well. Have remarkably good sense of smell. Most solitary, some in pairs or family groups. Food: vertebrates, carrion, less often invertebrates and plants. Most resident; some undertake long-range seasonal movements. Monogamous. Sexually mature at 1 year. Some species have male parental care.

Key :

Species Accounts:
Name Habitat Food Breeding biology Notes
Canis lupus prefers contiguous forested stands ungulates, rodents, mustelids 62-75 ds; 6 young/ litter, sexual maturity at 2 y Live in packs of 5-8 ind., sometimes pair for life
Canis latrans all landscapes; prefers bushy, open areas predators with omnivorous tendencies 60-63 ds; 4-7 young/litter Live in pairs or solitary
Vulpes vulpes fragmented forests, agricultural areas, disturbed habitats omnivorous, rabbits and hares, small rodents; 49-58 ds/ 4-6 young/litter Intensive fights among males during pairing
Urocyon cinereoargenteus forests, open brushy areas mostly plant material, also small animals Climbs trees well - the only species in the family; not found in MT
Alopex lagopus tundra-to forest-tundra Omnivorous 49-56 ds; up to 25 young/litter. Long range (thousands of km seasonal movements); complex multi-layer dens; seasonal change of color; not found in MT

Familia Felidae Gray, 1821

(4 genera)Species Accounts

Body length 46-317 cm, tail length 15-114 cm, weight 2.5-390 kg. Short neck and round head. Digitigrade, front legs 5 digits, hind legs 4 digits. All species, but cheetah have retractable claws. Worldwide distribution, except Antarctica, Australia and some islands. Mostly closed, forested landscapes, but also semi-deserts and deserts. Terrestrial, but climb trees well. Very specialized predators. Food: birds, fish, rodents, various mammals. Sight and wait-and-strike hunters. Solitary, some in family groups. Felis silvestris libycadomesticated in Egypt 4-3 thousand years ago.

Species Accounts:
Name Habitat Food Breeding biology
Lynx rufus semi-deserts and sagebrush grasslands to dense coniferous forests (MT is n. edge of range in N. America) birds, rodents 70 ds; 2-3 young/litter
Lynx lynx boreal forests, closely associated with denser forests; also forages in second-growth younger-aged stands (MT is s. edge of range in N. America) moose, caribou, hares and rodents 67-74 ds; 3-4 young/litter; lactation 3-4 months
Felis concolor brushy, open areas, forests, mountain areas deer and elk 82-96 ds; 1-6 young/litter; 1 litter/ 2-3 y

Laboratory 4 :


ORDER INSECTIVORA --- Family Soricidae;

ORDER LAGOMORPHA -- Family Ochotonidae &

Family Leporidae

O. Didelphimorphia ---Family Didelphidae Gray, 1821 (12 genera).

Didelphis virginiana Hind foot with opposable thumb and lacking claw, tail scaly; females with abdominal pouch. Uses tail to climb; 13 nipples located in ring (one in the center). Famous for playing dead; Lives in cavities; Accumulates lots of fat in the fall and can remain inactive for long time. Omnivorous; 2 litters/year; 12-13 ds pregnancy; 8-18 young/litter. Young attach to the nipple for up to 70 ds and then spend one month on mother's body. Only marsupial found in North America; First recorded in Montana in 1989 - moving into state from Idaho after having been released into the Seattle area approximately 10-15 years ago; prehensile tail, well-developed pouch; nocturnal and omnivorous; most generalized marsupial; unique dental formula: 5/4 1/1 3/3 4/4 = 50;

O. Insectivora - Family Soricidae Gray, 1821 (21 genera)Species Accounts:

Body length from 3.5 (smallest in Mammalia) to 18 cm; tail 1-112 cm, mass 2-3 g. 5 digits. Sometimes web between digits. Teeth 3/2; 0-1/0;1-3/1; 3/3 = 26-32. See lab manual for tooth appearance. Worldwide distribution, except polar regions, Australia & S.America. Most species prefer moist environments, some semi-aquatic. Solitary. Most activity late in afternoons and at night, otherwise all the time. Do not hibernate. Food- mostly invertebrates. 2-3 litters/year; 4-14 young/litter. Pregnancy 13-28 ds.

Species Accounts:
Species Range Habitat Food Reproductive


Sorex vagrans Alaska, western Canada, Pacific Coast, to Montana, south to Mexico. Only found in western portion of the state; is replaced by Sorex monticolusas you move eastward prefers moist forested habitat where it out competes S. cinereus Insectivorous breeds in spring and summer with average litter size of approximately 4-5; gestation 20 days Weight = 4-5 grams; generally darker in coloration , black-brown, than S. cinereus, and has a light gray ventral surface; lives approximately 14-16 months in the wild;
Sorex cinereus Alaska to Nova Scotia across all of the Canadian provinces and it extends to Washington and across the northern United States Generally associated with drier coniferous forests. Prefers a lot of ground structure (leaves, dead material); Insectivorous Active throughout the year. Begins breeding in March-April with peak in May; May have more than one litter/year with 2-10 per litter; This species has the largest range of the 29 species of Sorex in North America. It is one of the most common shrews in the country and the most common in Montana Brownish dorsally and grayish on the venter. Weight = 3.5 grams Lives 14-16 months
Blarina brevicauda Eastern U.S. and Canada from Manitoba to Texas and eastward to Atlantic Coast Habitat: found in all habitats; the most fossorial of all American shrews; lives in logs or stumps; builds nests of grass and leaves; active all year, day and night; Insectivorous though will eat some plant material Breeds spring to fall; 3 litters/year; litter size 5-7, gestation 21 days; Weight: 15-30 grams; Dark black to slate colored with undersides slightly lighter; Submaxillary glands secrete a poison that acts on the nervous system of prey species; Extends to the northwestern corner of North Dakota within 4 miles of the Montana border, so

O. Lagomorpha - Family Ochotonidae Thomas, 1897 (1 genus)

Ochotona princeps - Pika, rock-rabbit, cony. Found at higher elevations throughout the western United States from British Columbia southward to California, Colorado, and New Mexico. Smallest lagomorph in Montana. Has distinctive small, rounded ears (unlike other lagomorphs), forefeet are similar in size to hindfeet, and the tail is very small and not readily observable. Weight = 150 grams. Lives in boulder fields where it is active year-round; It accumulates vegetation which it stores in "hay piles" for use during the winter. Is a solitary species; males and females establish separate home ranges. Breeds twice: once in the spring just as the snow is melting off and again in mid-summer. Most often only raises one litter. Gestation is 30 days and litter sizes average 2-4.

O. Lagomorpha - Family LeporidaeGray, 1821 (10 genera) --Species Accounts

Body length 25-74 cm. Females usually larger than males. Large ears; 5 digits front legs with prominent reduction of first digits; Hind legs longer; 2-3 seasonal changes of fur/ year. Active at dawn and at night. Active year around, don't hibernate. Can move with up to 70 km/h speed. Mostly solitary. Hares vs. Rabbits - Hares are born precocious and the young are raised without a defined nest. Rabbits are born in a more altricial state in a well-constructed, fur-lined burrow.

Species Accounts:
Species Range Habitat Food Breeding Biology Comments
Lepus americanus Alaska across the Canadian Provinces; extends along the west coast and Rocky Mountain chain and across the northern United States prefers montane coniferous forested stands; will appear in forest openings but avoids large open areas like clear cuts; Breeds in the Spring Changes color in the winter
Lepus californicus Extensive range covering 2/3 of the United States; from California to Missouri and from Washington to central Mexico. Confined to the southwestern corner of Montana where it is found in sympatry with the white-tailed jackrabbit. Prefers sagebrush desert and semi-desert habitats in Montana.. Has a bounding gate unlike cottontail rabbits Strictly herbivorous Breeds most likely in early Spring-early Summer in Montana. Gestation 41-47 days with an average litter size of 2-3. May produce 2-4 litters per season Technically a hare, not a rabbit Distinguishing characteristic: black-tipped tail on dorsal surface - ventral surface of tail white; Body coloration can vary from gray to blackish; Does not change color to white in the winter as do the other two species of Lepus in Montana. Weigh
Sylvilagus floridanus Widespread throughout the eastern United States extending from Canada to Mexico. Montana is the northwestern extreme of its range. Here it is found in the southeastern corner of the state. Occupies a variety of habitats from deserts to swamps and hardwood forests. Found along riparian zones in Montana. Has a scampering gate.. Strictly herbivorous Begins breeding in January/February and may breed into September. Gestation of 28-29 days with litter sizes of 3-6. May produce 5-7 litters per year. Is a large sylvilagid, the largest found in Montana. Coat coloration varies from brown to gray giving this species a grissled appearance. Weight = 0.8-1,4 kg. Constructs a shallow nest during the summer but may use other species' underground burrows during the

Laboratory 5:

ORDER CHIROPTERA --- Family Vespertilionidae Species Accounts

The order Chiroptera is divided into two suborders, Megachiroptera and Microchiroptera. Suborder Megachiroptera, the Old World fruit and nectar feeding bats, contains only one family (Pteropodidae) with 42 genera and 166 species. Suborder Microchiroptera contains 16 families, 135 general, and 759 species. The combined number of species (925) makes this order the second largest order of mammals behind Order Rodentia.

Bats are found on every continent except Antarctica and are absent from only a few oceanic islands. The diets of bat species vary widely, with insectivory being most common. Various batspecies consume nectar, pollen, vertebrates, plant foliage, flowers, fruit, and even blood. Roosts may be found in caves, rock crevices, beneath exfoliating bark, hollow trees, and also man-made structures. This order contains species of incredible ecological diversity!

Montana is home to 14 species of bats. All but two Montana species roost in caves or man-made structures. The hoary bat roosts in tree foliage, and the silver-haired bat roosts in bark crevices. These roost preferences may explain the fact that all but these three species give birth to more than one pup per year. Cave roosting species nearly always give birth to one offspring, putting their energy into a single, large pup which may have a high chance of survival due to the relative safety of the cave environment. Foliage and bark roosting bats often give birth to twins, and triplets or quadruplets may occasionally be seen.

Many bats use a reproductive strategy called delayed fertilization. Mating occurs in the late fall, but the female's egg is not fertilized until early spring. Parturition takes place from early June to mid-July. The gestation period varies widely in response to environmental conditions. A cold, rainy spring may result in a later parturition date, while a warm, dry spring may result in an earlier one. Pups grow rapidly. By approximately 3 weeks of age, they are able to fly, and by approximately 5-6 weeks, they are weaned.

Of the species you have studied in lab, Eptesicus fuscus and Myotis lucifugus, are known to overwinter in hibernacula in Montana. Lasiurus cinereus, Lasionycterus noctivagans, Antrozous pallidus, and Euderma maculatum migrate south during winter. Corynorhinus townsendii has been observed hibernating in the state, but no large aggregations have been observed, suggesting that many members of this species may also migrate outside the state during winter.

Species Accounts:
Species Roosting Sites;

other biology

Gestation Period&Litter Size Year-round Resident Status in MT
Eptesicus fuscus Caves, mines, and man-made structures. ~60 days


Yes Common but not abundant.
Lasionycterus noctivagans Bark crevices; coniferous forests near rivers, lake , mountain forests 50-60 days


No Common, though infrequent.
Lasiurus cinereus Tree foliage; solitary. ~90days


No Locally common, but never abundant.
Myotis lucifugus Buildings, mines, caves, trees, rock crevices, snags 50-60 days


Yes Common through-out the state.
Corynorhinus townsendii Cold caves and mine shafts; females can form colonies up to 200 ind. during breeding season, while males are solitary; Slow flight, can hover; feed during flight, can pick insects from ground 56-100 days


Yes (??) Rare; Isolated pops.; Species of special concern.


Antrozous pallidus Rock crevices and man-made structures; Low flight, can pick prey on ground 60-65 ds


No Considered rare.


Euderma maculatum Cliffs and steep canyon walls; open bushy areas; solitary ????


No Extremely rare.

Laboratory 6 & Laboratory 7


Family Cervidae, Suidae, Dicotylidae, Bovidae Species Accounts

Key 1:

Key 2


Species Accounts:
Species Name Range Habitat General Life History
Family Cervidae      
Odocoileus virginanus

White-tailed deer

Southern Canada, most of U.S. except parts of the Southwest, down to Brazil Prefers more riparian habitat, dense forest. Rut begins in Oct; Births occur April-June; Twinning common (triplets seen occasionally). Sometimes hybridize w/ O. hemionus. Browser and grazer. Pregnancy 200-212 ds; Live up to 15 yrs
Odocoileus hemionus

Mule Deer

S. Yukon to California & N. Mexico; In U.S. they are predominantly found in the West. Prefers more open, arid habitat. Sage and scrub. Similar to above.


Rangifer tarandus

Caribou or Reindeer

Circumpolar, down through Canada. Arctic tundra and boreal forests though S. pops. are found in mountainous areas. Many herds undergo large migrations to spring/summer feeding/calving grounds; Usually one, rarely two calves; Pregnancy 192-246 ds; Only Cervid in which both males and females have antlers; Eats lichens and evergreens in fall, green leaves/shoots in spring & summer. Poor protein diet results in frequent consumption of bird eggs, rodents, etc. Widely domesticated.
Alces alces


Found from N. Europe to Siberia; Alaska to Colorado Wooded areas close to moist, marshy areas. Solitary or in groups 4-5; Mates in Sept-Oct; Pregnancy 237 ds; 1-2 calves born in spring (usually 1); Sexual maturity at 3 yrs; Live up to 20 yrs; Eats willows, poplars, and aquatic veg; Can submerge completely to feed on bottom. Domesticated in some areas
Cervus elaphus

American Elk, Wapiti, or Red deer

Europe, Asia, China, Africa, Canada, and NW U.S.; Varies; Prefers heavily timbered areas for rest and thermal cover. More open areas for feeding. Primarily a grazer; Cows/calves form large summer herds; Bulls may form small groups and will violently defend harem of cows during Sept-Oct rut. Pregnancy 8 months. Sexual maturity at 2 yrs; Calves born in spring.
Family Suidae      
Sus scrofa

Domestic (feral) pig

Mainly found in the E and SE U.S. Primarily wooded areasand barnyards. 4-12 young; gestation period 16-17 wks. Omnivorous, but mainly roots and bulbs.
Family Dicotylidae      
Tayassu tajacu

Collared peccary

Native to SW U.S. extending S. toward Argentina. Brushy, semidesert, oaks, chaparral, mesquite. 1-5 young; Gestation period 142-148 days; Omnivorous, nuts, fruits, berries, grubs, bird eggs. Breeds throughout the year.


Geographic Range Habitat Life History
Family Bovidae      
Ovis canadensis

Bighorn Sheep

Southwestern Canada, western U.S. to California and northern Mexico. Alpine meadows, mountain slopes, Prefers grasses, sedges, and forbs; May be seen at lower elevations in winter. Breeds in fall; 1-4 (usually 1-2) young born in spring. Gestation period approx. 180 days; males sexually mature when1.5-3 yrs, males usually breed when 4-5 yrs of age. Gregarious, but males and females usually segregate until fall rut. Dominant male usually one w/ largest horns. Weighs: 50-143kg (males), 30-70kg (females)
Ovis dalli

Dall's Sheep

Alaska, northwestern Canada. Rough terrain and mountain slopes. Similar to O. canadensis. Similar to above. Weighs: 55-90kg.
Oreamnos americanus

Mountain Goat

Alaska to Oregon and Montana. Not a true goat, but more closely related to antelope (true antelope, not pronghorns). Steep cliffs in alpine and subalpine tundra. Varied diet of grasses, moss, lichens, woody plants & herbs. Males and females usually segregate except during rut. Breed Nov-Jan. w/ 1-2 young born in May/June. Weighs: 45-135kg.
Bison bison


Patchy distribution throughout the western U.S. and into parts of Alberta and Manitoba. (Some domesticated herds now exist). Open plains and grasslands. Primarily a grazer. (May be found in wooded areas with openings in N. Canada). Gregarious, forming extensive herds; Form wallows of dust and mud. Breed from July-October w/ normally 1 calf. Gestation period ~9 mos. Lactation up to 1 yr, mature when 2-3 yrs. Live 25-30 yrs. (Adults enjoy terrorizing stupid tourists in national parks.) Weighs: 360-900 kg.
Ovibos moschatus


Extreme northern Canada and northeastern Alaska; Arctic Islands, reintroduced to Eurasian Arctic coast. Arctic tundra. Eats tundra grasses, willows, forbs, sedges. Usually give birth to 1 young every other year. Breed in July-August. May occur singly, but small groups are more common in summer, large groups in winter. Form circle with heads facing outward when confronted by predators. Extensive development of 2nd and 5th digits. Weighs: 225-405 kg.
Family Antilocapridae      
Antilocapra americana


Endemic to North America. Western U.S. (*only extant member of its family and genus). Grasslands, prairies, and semi-desert sagebrush plains. Primarily a browser, but also eats forbs. Males and females have horns. Horn sheaths are branched and shed annually. Fastest land mammal in N. America - can run with speeds up to 40 mph, 95 km/h. Sexual maturity: females at 16 months, males at 24 months of age. Mate from July to Oct. Twinning is common. Gestation period 230-240 days.Weighs: 33-60 kg. Live 8-10 yrs.