Animal Diversity Web

Di­ver­sity

Neotom­i­nae is a large New World sub­fam­ily of rat-like or mouse-like cricetid ro­dents. This group in­cludes the pack­rats and woodrats, as well as the fa­mil­iar deer and white-footed mice. There are 124 neotomine species in 16 gen­era, dis­trib­uted among four tribes. (Musser and Car­leton, 2005)

Ge­o­graphic Range

Neotomines are dis­trib­uted through­out North Amer­ica, from Panama to Alaska and north­ern Canada. (Nowak, 1999)

• Biogeographic Regions
• nearctic
  • native
• neotropical
  • native

Habi­tat

These ro­dents oc­cupy a wide va­ri­ety of habi­tats, in­clud­ing prairies, sa­van­nahs, moun­tains, deserts, marshes, agri­cul­tural fields, sub­ur­ban human dwellings, for­est edges, scrub forests, rain­for­est, conif­er­ous for­est, and tem­per­ate and trop­i­cal de­cid­u­ous for­est. (Nowak, 1999)

• Habitat Regions
• temperate
• tropical
• terrestrial

• Terrestrial Biomes
• taiga
• desert or dune
• savanna or grassland
• chaparral
• forest
• rainforest
• scrub forest
• mountains

• Wetlands
• marsh
• swamp
• bog

• Other Habitat Features
• suburban
• agricultural
• riparian

Phys­i­cal De­scrip­tion

Neotomines are mouse-like or rat-like in over­all ap­pear­ance, with long tails and promi­nent ears. Their head and body length ranges from 50 to 351 mm, and their tails range from 35 to 240 mm. They weigh 6 to 450 grams. In some species, males weigh more, and are some­times longer than fe­males (Schulte-Hostedde et al. 2001). Male neotomines often have promi­nant ven­tral se­ba­ceous glands, but they usu­ally lack rump, hip, and flank glands. The pelage is usu­ally dense, ranges from short to long, and can be ei­ther coarse or soft. Neotomines range in color from pale to very dark, and they are yel­low­ish, red­dish, brown, or gray on their dor­sal sur­face and buffy, gray­ish, red­dish, or white below. Some pop­u­la­tions con­sist of more than one color morph (Smith 1972). The tail is sparsely haired or bushy with a tufted tip and ranges from long and skinny to short and fat. The large ears are usu­ally sparsely haired.

The neotomine den­tal for­mula is 1/1, 0/0, 0/0, 3/3 = 16. The in­cisors are usu­ally or­tho­dont or opistho­dont, and the mo­lars are rooted and have a bis­e­r­ial cusp arrange­ment (in con­trast to the tris­e­r­ial cusp arrange­ment of most murines). Each molar has a lon­gi­tu­di­nal enamel crest (mure or murid). The mo­lars range from brachy­dont to hyp­sodont, and the third mo­lars are usu­ally smaller than the sec­ond mo­lars. Neotomine skulls have flat or slightly re­cessed ptery­goid fos­sae, and small to medium-sized au­di­tory bul­lae. In ad­di­tion, the mas­toid bul­lae are not hy­per­tro­phied, and an ac­ces­sory tym­pa­num is al­ways pre­sent. The malleus is of par­al­lel con­struc­tion. Other neotomine skull char­ac­ter­is­tics vary widely. A skele­tal char­ac­ter­is­tic shared by most neotomines is the pres­ence of a promi­nant neural spine on the sec­ond tho­racic ver­te­bra. Fi­nally, neotomines have one- or two-cham­bered stom­achs, and the tongue bears a sin­gle cir­cum­val­late papilla. (Car­leton and Musser, 1984; Nowak, 1999; Schulte-Hostedde, et al., 2001; Smith, 1972)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry
• polymorphic

• Sexual Dimorphism
• sexes alike
• male larger

Re­pro­duc­tion

Many neotomines are promis­cu­ous, and males and fe­males only as­so­ci­ate for the brief time re­quired for mat­ing. Oth­ers are polyg­y­nous or monog­a­mous. In some species, a cop­u­la­tory plug forms dur­ing mat­ing and seals the fe­male's re­pro­duc­tive tract, hin­der­ing the suc­cess of mat­ings with other males. (Car­leton and Musser, 1984; Gu­ber­nick and Teferi, 2000; Nowak, 1999)

• Mating System
• monogamous
• polygynous
• polygynandrous (promiscuous)

Neotomines are ca­pa­ble of re­pro­duc­ing year round, al­though for some pop­u­la­tions there is a de­cline in re­pro­duc­tion dur­ing the win­ter months and a peak in the spring and sum­mer. Ovu­la­tion is spon­ta­neous. Fe­males of some species ex­pe­ri­ence a post­par­tum es­trus and con­ceive their next lit­ter while nurs­ing the first, al­though the em­bryos do not im­plant until lac­ta­tion ceases. Ges­ta­tion lasts 20 to 40 days, and there are any­where from one to nine young per lit­ter, al­though lit­ters of two to three are most com­mon. The young are born blind and naked, and their eyes open be­tween 11 and 21 days after birth. They nurse for three to four weeks. They often re­main with their mother for a month after wean­ing. Fe­males reach sex­ual ma­tu­rity as young as 28 days, while males reach sex­ual ma­tu­rity when they are at least 42 days old. (Car­leton and Musser, 1984; Nowak, 1999)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
  • internal
• viviparous
• delayed implantation
• post-partum estrous

Fe­males build nests where they nurse their al­tri­cial young for three to four weeks. In some species, males as­sist fe­males in car­ing for their off­spring, groom­ing them, car­ry­ing them, and hud­dling with them. In fact, such male parental care has been shown to en­hance sur­vival of the young (Gu­ber­nick and Teferi 2000). (Gu­ber­nick and Teferi, 2000; Nowak, 1999)

• Parental Investment
• altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • male
    • female

Lifes­pan/Longevity

Most neotomines do not live more than a year in the wild. The record lifes­pan in cap­tiv­ity is eight years, five months. (Nowak, 1999)

Be­hav­ior

Neotomines are ter­res­trial, ar­bo­real, or semi­ar­bo­real ro­dents. Their feet are mod­i­fied for run­ning or for climb­ing. Those that are ter­res­trial often build run­ways through ground veg­e­ta­tion or through leaf lit­ter that they fol­low as they go about their daily busi­ness. Neotomines can be noc­tur­nal, di­ur­nal, or cre­pus­cu­lar. They are ac­tive year round, though some ex­pe­ri­ence bouts of tor­por dur­ing cold weather. Some species dig bur­rows or use those made by other an­i­mals, oth­ers build elab­o­rate nests on the ground or in trees, and some sim­ply shel­ter in nat­ural crevices. Some neotomine species are soli­tary, ter­ri­to­r­ial, and ag­gres­sive, while oth­ers are fairly so­cial and may even share nests with sev­eral con­specifics. (Nowak, 1999)

• Key Behaviors
• arboreal
• scansorial
• cursorial
• terricolous
• diurnal
• nocturnal
• crepuscular
• motile
• daily torpor
• solitary
• territorial
• social

Com­mu­ni­ca­tion and Per­cep­tion

Neotomines have acute senses of smell, touch, hear­ing, and vi­sion. They com­mu­ni­cate with a va­ri­ety of calls, chirps, and even minia­ture "wolf" howls. Some neotomines com­mu­ni­cate with ul­tra­sounds (Smith 1972), and they oc­ca­sion­ally drum their front feet rapidly on the ground when alarmed. Chem­i­cal sig­nal­ing with pheromones and scent marks is an ex­tremely im­por­tant as­pect of com­mu­ni­ca­tion in this group, as these odors can quickly send a sig­nal about the iden­tity and sta­tus of an in­di­vid­ual (Ma et al. 1999). (Ma, et al., 1999; Nowak, 1999; Smith, 1972)

• Communication Channels
• acoustic
• chemical

• Other Communication Modes
• pheromones
• scent marks

• Perception Channels
• visual
• tactile
• acoustic
• ultrasound
• chemical

Food Habits

Neotomines range from her­biv­o­rous to car­niv­o­rous in their eat­ing habits. Foods con­sumed in­clude seeds, roots, stems, cacti, pine nee­dles, leaves, nuts, fungi, in­sects, scor­pi­ons, other ro­dents, and car­rion. Many store food in­side of their bur­rows for later con­sump­tion. (Nowak, 1999)

• Primary Diet
• carnivore
  • eats terrestrial vertebrates
  • insectivore
  • eats non-insect arthropods
  • scavenger
• herbivore
  • folivore
  • frugivore
  • granivore
• omnivore
• mycophage

• Foraging Behavior
• stores or caches food

Pre­da­tion

These ro­dents are preyed upon by a va­ri­ety of other an­i­mals, in­clud­ing hawks, owls, snakes, and car­niv­o­rous mam­mals. Neotomines may avoid pre­da­tion by de­creas­ing their ac­tiv­ity level on bright, moon­lit nights (Top­ping et al. 1999), and by hav­ing fur that matches their back­ground (Kauf­man 1974). Ad­di­tion­ally, some neotomine species have tails that break off eas­ily when grabbed, al­low­ing es­cape. (Car­leton and Musser, 1984; Kauf­man, 1974; Nowak, 1999; Top­ping, et al., 1999)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • hawks Accipitridae
  • owls Strigiformes
  • snakes Serpentes
  • mammalian carnivores Carnivora

Ecosys­tem Roles

Neotomines are pri­mary and higher-level con­sumers, and they are a sta­ple food source for var­i­ous preda­tors. Also, they im­pact for­est re­gen­er­a­tion by con­sum­ing seeds and tree seedlings (Cote et al. 2003) and they may be im­por­tant dis­persers of my­c­or­rhizal fungi (Man­gan and Adler 2000). Fi­nally, neotomines are par­a­sitized by ticks and mites, fleas, lice, bot flies, ne­ma­todes, and flukes (Kin­sella 1991). (Cote, et al., 2003; Kin­sella, 1991; Man­gan and Adler, 2000; Nowak, 1999)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Neotomines are bred in cap­tiv­ity and used as lab an­i­mals for ge­netic and phys­i­o­log­i­cal re­search. (Nowak, 1999)

• Positive Impacts
• research and education

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Some neotomines are vec­tors of human dis­eases, in­clud­ing han­tavirus and lyme dis­ease. Also, they are con­sid­ered nui­sance an­i­mals when they enter homes, raid food stores, gnaw on house­hold goods, and build nests in un­wel­come places. (Nowak, 1999)

• Negative Impacts
• injures humans
  • carries human disease
• household pest

Con­ser­va­tion Sta­tus

The IUCN lists 15 neotomine species as lower risk, 9 species as vul­ner­a­ble, 13 species as en­dan­gered (6 Neotoma species, 5 Per­omyscus species, Jico deer mice, Habromys sim­u­la­tus, and Cozumel har­vest mice, Re­i­throdon­to­mys spectabilis), and 2 species as crit­i­cally en­dan­gered (Slevin's mice, Per­omyscus slevini, and false canyon mice, Per­omyscus pseudocrini­tus, both of Mex­ico). In ad­di­tion, one species has gone ex­tinct re­cently (Pem­ber­ton's deer mice, Per­omyscus pem­ber­toni, from San Pedro No­lasco Is­land in Mex­ico). Many neotomine species have small, re­stricted ranges, nar­row habi­tat re­quire­ments, and are threat­ened by en­croach­ing human de­vel­op­ment. (IUCN, 2004)

• IUCN Red List [Link]

  Not Evaluated

Other Com­ments

The ear­li­est fos­sils of ex­ist­ing neotomine gen­era are from the late Miocene of North Amer­ica. (Musser and Car­leton, 2005)

Con­trib­u­tors

Tanya Dewey (ed­i­tor), An­i­mal Di­ver­sity Web.

Al­li­son Poor (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Car­leton, M., G. Musser. 1984. Muroid ro­dents. Pp. 289-379 in S An­der­son, J Jones Jr., eds. Or­ders and Fam­i­lies of Re­cent Mam­mals of the World. New York: John Wiley and Sons.

Cha­line, J., P. Mein, F. Pet­ter. 1977. Les grandes lignes d'une clas­si­fi­ca­tion évo­lu­tive des Muroidea. Mam­malia, 41: 245-252.

Cote, M., J. Fer­ron, R. Gagnon. 2003. Im­pact of seed and seedling pre­da­tion by small ro­dents on early re­gen­er­a­tion es­tab­lish­ment of black spruce. Cana­dian Jour­nal of For­est Re­search, 33(12): 2362-2371.

Eller­man, J. 1941. The Fam­i­lies and Gen­era of Liv­ing Ro­dents, vol. II. Lon­don: British Mu­seum (Nat­ural His­tory).

Gu­ber­nick, D., T. Teferi. 2000. Adap­tive sig­nif­i­cance of male parental care in a monog­a­mous mam­mal. Pro­ceed­ings of the Royal So­ci­ety of Lon­don, 267(1439): 147-150.

Hooper, E., G. Musser. 1964. The glans penis in neotrop­i­cal cricetines (Fam­ily Muri­dae) with com­ments on the clas­si­fi­ca­tion of muroid ro­dents. Mis­cel­la­neous Pub­li­ca­tions of the Mu­seum of Zo­ol­ogy of the Uni­veristy of Michi­gan, 123: 1-57.

IUCN, 2004. "2004 IUCN Red List of Threat­ened Species" (On-line). Ac­cessed June 27, 2005 at www.​redlist.​org.

Jansa, S., M. Wek­sler. 2004. Phy­logeny of muroid ro­dents: re­la­tion­ships within and among major lin­eages as de­ter­mined by IRBP gene se­quences. Mol­e­c­u­lar Phy­lo­ge­net­ics and Evo­lu­tion, 31: 256-276.

Kauf­man, D. 1974. Adap­tive col­oration in Per­omyscus po­liono­tus: ex­per­i­men­tal se­lec­tion by owls. Jour­nal of Mam­mal­ogy, 55(2): 271-283.

Kin­sella, J. 1991. Com­par­i­son of helminths of 3 species of mice, Podomys flori­danus, Per­omyscus gossyp­i­nus, and Per­omyscus po­liono­tus, from south­ern Florida. Cana­dian Jour­nal of Zo­ol­ogy, 69(12): 3078-3083.

Ma, W., D. Wiesler, M. Novotny. 1999. Uri­nary volatile pro­files of the deer­mouse (Per­omyscus man­ic­u­la­tus) per­tain­ing to gen­der and age. Jour­nal of Chem­i­cal Ecol­ogy, 25(3): 417-431.

Man­gan, S., G. Adler. 2000. Con­sump­tion of ar­bus­cu­lar my­c­or­rhizal fungi by ter­res­trial and ar­bo­real small mam­mals in a Pana­man­ian cloud for­est. Jour­nal of Mam­mal­ogy, 81(2): 563-570.

Michaux, J., A. Reyes, F. Catze­flis. 2001. Evo­lu­tion­ary his­tory of the most spe­ciose mam­mals: mol­e­c­u­lar phy­logeny of muroid ro­dents. Mol­e­c­u­lar Bi­ol­ogy and Evo­lu­tion, 18: 2017-2031.

Miller, G., J. Gi­d­ley. 1918. Syn­op­sis of su­per­generic groups of ro­dents. Jour­nal of the Wash­ing­ton Acad­emy of Sci­ence, 8: 431-448.

Musser, G., M. Car­leton. 2005. Su­per­fam­ily Muroidea. D Wil­son, D Reeder, eds. Mam­mal Species of the World. Bal­ti­more and Lon­don: The Johns Hop­kins Uni­ver­sity Press.

Nowak, R. 1999. Walker's Mam­mals of the World, vol. 2. Bal­ti­more and Lon­don: The Johns Hop­kins Uni­ver­sity Press.

Reig, O. 1980. A new fos­sil genus of South Amer­i­can cricetid ro­dents al­lied to Wiedomys, with an as­sess­ment of the Sig­mod­on­ti­nae. Jour­nal of Zo­ol­ogy, 192: 257-281.

Schulte-Hostedde, A., J. Mil­lar, G. Hick­ling. 2001. Sex­ual di­mor­phism in body com­po­si­tion of small mam­mals. Cana­dian Jour­nal of Zo­ol­ogy, 79(6): 1016-1020.

Simp­son, G. 1945. The prin­ci­ples of clas­si­fi­ca­tion and a clas­si­fi­ca­tion of mam­mals. Bul­letin of the Amer­i­can Mu­seum of Nat­ural His­tory, 85: 1-350.

Smith, J. 1972. Sound pro­duc­tion by in­fant Per­omyscus man­ic­u­la­tus (Ro­den­tia:My­omor­pha). Jour­nal of Zo­ol­ogy, 168: 369-379.

Smith, M., J. Car­mon, J. Gen­try. 1972. Pelage color poly­mor­phism in Per­omyscus po­liono­tus. Jour­nal of Mam­mal­ogy, 53(4): 824-833.

Step­pan, S., R. Ad­kins, J. An­der­son. 2004. Phy­logeny and di­ver­gence-date es­ti­mates of rapid ra­di­a­tions in muroid ro­dents based on mul­ti­ple nu­clear genes. Sys­tem­atic Bi­ol­ogy, 53(4): 533-553.

Top­ping, M., J. Mil­lar, J. God­dard. 1999. The ef­fects of moon­light on noc­tur­nal ac­tiv­ity in bushy-tailed wood rats (Neotoma cinerea). Cana­dian Jour­nal of Zo­ol­ogy, 77(3): 480-485.

Tull­berg, T. 1899. Uber das sys­tem der nageth­iere: eine phy­lo­genetis­che studie. Nova Acta Re­giae So­ci­etatis Sci­en­tiarum Up­salien­sis, 3: 1-514.