This book is about the wild mammals that inhabit Minnesota today or that have done so in the recent past. Its primary aims are to describe these mammals briefly, to aid in their identification, to present their known distribution in some detail, and to provide an introduction to their natural history. It also provides information on the interaction of these species with people, and lists references on the mammals of this state as well as some more general works. I hope thatThe Mammals of Minnesotawill be useful to the general reader and to students in biology, zoology, mammalogy,...

This section comprises accounts of the wild species of mammals that occur, or have occurred, in Minnesota in Recent times, along with introductions to the orders, families, and genera to which these species are assigned. Each species account includes measurements, a description of appearance, comments on range and habitat, a distribution map, sections on natural history and interaction with people, and a list of references. Many of the accounts include a drawing of the mammal in its natural surroundings and/or a skull drawing. Skulls labeled BSCVC are in the vertebrate collections of Bemidji State University; those labeled MMNH are in...

Most authors have previously placed all members of the infraclass Metatheria in the single order Marsupialia. Others, however, have concluded that enough variation occurs within the group to justify dividing it into three or four orders. The common term “marsupial” will doubtless continue to be used, just as the term “placental” is employed for all orders in the infraclass Eutheria. The classification here follows Kirsch (1977b).

Female marsupials bear their young after a very short gestation period, and most have a pouch in which the nipples are located and within which the young nurse and continue their growth and development....

The Insectivora is the third largest order of mammals. Most of the species are small, but some are as large as a rabbit. Insectivores are hard to characterize as a group, partly because some families of doubtful affinities are often classified in the order, and partly because the group retains many primitive characters that have changed little since the Cretaceous, some of which characters are also possessed by ancient species that are generally assigned to other orders (Findley 1967; Van Valen and Sloan 1977; Vaughan 1978). The ordinal name implies a diet of insects, and, indeed, insects and other invertebrates...

Bats are the only mammals capable of powered flight. As in birds, the forelimb functions as a wing. The flight membrane of bats, however, consists not of stiff epidermal derivatives like the feathers of birds, but of a living layer of skin and associated tissues, the patagium. The patagium is supported by the arm, the greatly elongated second through fifth digits, the sides of the torso, the hind legs, and, in most bats, the tail (Norberg 1969, 1972). Although birds and bats are both diverse groups, bats are generally adapted for slower flying speeds than birds, and for greater mobility....

The order Lagomorpha is relatively small, including only two extant families, the Ochotonidae (pikas) and Leporidae (rabbits and hares). Only the latter occur in Minnesota. At one time, biologists classified lagomorphs as a suborder of the order Rodentia. The consensus today is that most resemblances between the two groups, other than those typical of placental mammals in general, are the result of convergent evolution (McKenna 1969).

Many features, especially of the skull and skeleton, together distinguish the lagomorphs from other mammals. Only a few are given here. Lagomorphs have evergrowing incisors, separated from the cheek teeth in each jaw by...

Rodents make up the largest order of mammals, constituting about 40 percent of all living species. They are also the most widespread wild terrestrial mammals, occurring naturally on all the continents except Antarctica, and on many oceanic islands. They are the only terrestrial placental mammals that have successfully colonized Australia without the aid of people. Members of one family (rats and mice of the Old World family Muridae) also have followed people wherever they have gone, except to the moon and perhaps Antarctica.

Rodents are easily distinguished from all other North American mammals. The upper and lower jaws each bear...

The order Carnivora includes some of our best-known mammals. Although “carnivore” means meat eater, few carnivores eat only meat, and some (like the giant panda) are strict vegetarians. All Minnesota carnivores eat at least some animal matter. Our species range in size from the least weasel, which is about as heavy as a meadow vole (40 or 50 g), to the black bear, which may reach 270 kg.

Wild carnivores occur on all continents except Antarctica, but the ancestors of the wild dog of Australia, the dingo, were probably introduced into that continent by people. Dogs are the most common...

Artiodactyls include pigs, hippopotami, camels, giraffes, deer, pronghorned antelope, Old World antelope, cattle, sheep, and goats. A diagnostic feature of the order is the astragulus (ankle bone). Both its upper and lower articulating surfaces are movable, an arrangement unique to the Artiodactyla. The weight-bearing axis of the foot passes between the third and fourth digits. Camels are digitigrade, walking on the toes, but most other artiodactyls are unguligrade, walking on hoofs that are modified claws (Koopman 1967). Because each foot has two hoofs, one on the third toe and the other on the fourth, artiodactyls are often referred to as...

Domestic mammals are those that people keep and breed. Examples include racehorses, dairy cows, retrievers, and white rats. Most cannot survive for long in the wild, but some can. People have selectively bred most of these species for so long that they differ substantially from their wild ancestors. Remains of all but the smallest domestic mammals are likely to be found outdoors, most often in modified habitats. The following is, to my knowledge, a complete list of species that people keep in Minnesota.

Oryctolagus cuniculus,domestic rabbit

Mesocricetus auratus,golden hamster

Merionesand other genera, gerbils

Rattus norvegicus,laboratory rat...

A key is a written (and sometimes illustrated) identification device. Ideally, with the key and appropriate measuring aids, you should be able to identify a single specimen collected in the geographic area covered by the key, without having to compare it with other specimens. For the two keys that follow, you will need a millimeter rule and perhaps metric calipers, and a hand lens or low-power microscope. If you are trying to identify a study skin, it should be one with standard measurements already on the label. Standard measurements can only be made from intact specimens, not from prepared skins....