Deomyinaespiny mice, forest mice, and relatives

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Diversity

Deomyinae is a relatively large subfamily of rodents in the family Muridae. There are 42 species in 4 genera in this subfamily, Acomys (spiny mice), Lophuromys (brush-furred rats), Uranomys (Rudd's mice), and Deomys (Congo forest mice). (Musser and Carleton, 2005)

Geographic Range

Deomyines are found throughout Africa and in the Middle East from Pakistan to Crete, where the species Acomys minous is endemic, and Cyprus, where the species Acomys nesiotes is endemic. (Nowak, 1999)

Habitat

Deomyines inhabit grasslands, savannahs, tropical and montane forests, semideserts, and swamps. They live at elevations from sea level to over 4,000 meters. (Nowak, 1999)

Physical Description

These mouselike rodents measure 70 to 175 mm in head and body length, and their tails measure 42 to 215 mm. They weigh 11 to 111 grams. They have large, prominent ears and most have long, thick fur. The fur of some species takes the form of stiff spines that cover the dorsal surface. Deomyines are reddish, pale yellow, dark brown, buff, or gray in color, sometimes with fine speckles or streaks, and their underparts are brown, white, cinnamon, cream, or dark orange. Some deomyine species are polymorphic, with melanistic black individuals appearing in the population. (Hubbard, 1972; Nowak, 1999)

  • Sexual Dimorphism
  • sexes alike

Reproduction

Some deomyines live in monogamous pairs, and males and females cooperate to raise their offspring (Menge and Alberts 2002). Others are solitary and promiscuous. (Menge and Alberts, 2002; Nowak, 1999)

Some deomyines concentrate their reproduction during the rainy seasons, when food is plentiful, and others breed year round. Some females have been known to bear more than 12 litters in a row with no break. This rapid succession of broods is facilitated by a postpartum estrus, which ensures that females become pregnant again immediately after giving birth. Gestation lasts four to six weeks, and litter sizes range from one to six. The young of some species are highly precocial and are born with their eyes open, and others take up to a week to open their eyes. Nursing lasts up to two weeks, and the young are sexually mature at two to three months of age. (Nowak, 1999)

Young deomyines ranges from precocial to altricial. Precocial young accompany their mother while she forages, having no nest in which to rest, and eat solid food on their first day. Altricial young clamp onto their mother's nipples and nurse almost continuously for several days. Males of some species participate in raising their offspring. Each male stays near his mate when she is giving birth, and then he joins the female in grooming the youngsters (Menge and Alberts 2002). (Hubbard, 1972; Menge and Alberts, 2002; Nowak, 1999)

  • Parental Investment
  • altricial
  • precocial
  • 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

Deomyines live as long as five years in captivity; lifespan in the wild is probably somewhat shorter. (Nowak, 1999)

Behavior

Deomyines are terrestrial rodents that are nocturnal, diurnal, or crepuscular. Some build nests under roots, rocks, or logs, or in simple burrows. Others simply shelter in rock crevices, gerbil burrows, or termite mounds. Some are good climbers, and others are capable of huge leaps when they are disturbed. Deomyines range from solitary and aggressive to gregarious, and some species live in monogamous pairs. (Nowak, 1999)

Communication and Perception

Pheromones are important tools of communication for these rodents, allowing them to recognize the age and sex of conspecifics (Porter and Doane 1979, Janus and Holman 1989). They perceive the world using visual, tactile, auditory, and chemical cues. (Janus and Holman, 1989; Nowak, 1999; Porter and Doane, 1979)

Food Habits

Deomyines primarily eat insects, especially ants. They also eat small vertebrates such as frogs, and vegetable matter such as grains and grasses. There are reports of deomyines cannibalizing conspecifics. (Hubbard, 1972; Nowak, 1999)

Predation

Deomyines are preyed upon by small mammalian carnivores, snakes, and owls. These rodents have some unique anti-predator adaptations. Some are covered with stiff spiny hairs, and others can leap 50 cm into the air when threatened. Some, such as common spiny mice (Acomys cahirinus), have evolved tails that break off easily when grabbed, temporarily distracting predators and giving them time to escape predation (Shargal et al. 1999). (Nowak, 1999; Shargal, et al., 1999)

Ecosystem Roles

Deomyines are primary, secondary, and tertiary consumers in their ecosystem. Some deomyine species are important pollinators (Fleming and Nicolson 2002). One species, Acomys cahirinus has become commensal with humans, populating urban areas. Deomyines are parasitized by several flea species, including Parapulex chephrenis, P. echinatus, Xenopsylla brasiliensis, Nosopsyllus incisus, Ctenopthalmus calceatus, C. evidens, C. grzimeki, C. verutus, C. eximius, Dinopsyllus lypusus, and D. longifrons. (Fleming and Nicolson, 2002; Hubbard, 1972; Nowak, 1999)

  • Ecosystem Impact
  • pollinates
Mutualist Species
Commensal/Parasitic Species

Economic Importance for Humans: Positive

Deomyines are easy to keep in captivity, and therefore they are used as laboratory animals and have become popular pets in some countries. (Nowak, 1999)

  • Positive Impacts
  • pet trade
  • research and education

Economic Importance for Humans: Negative

Deomyines may be resevoirs for plague and typhus in some areas. (Hubbard, 1972; Nowak, 1999)

  • Negative Impacts
  • injures humans
    • carries human disease

Conservation Status

There are 11 deomyine species on the IUCN's Red List of Threatened Species. One of these species is critically endangered (Asia Minor spiny mice, Acomys cilicicus), four Lophuromys species are near-threatened, three are vulnerable (black-clawed brush-furred rats, Lophuromys melanonyx, Dieterlen's brush-furred mice, Lophuromys dieterleni, and Crete spiny mice, Acomys minous), and three are not known well enough to make an assessment. These rodents, like many others, are threatened by human-induced habitat loss and degradation. A few protected areas have been established that may help preserve some of these species, but research and comprehensive management plans are still needed to prevent further declines. (IUCN, 2004)

  • IUCN Red List [Link]
    Not Evaluated

Contributors

Tanya Dewey (), Animal Diversity Web.

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

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

chemical

uses smells or other chemicals to communicate

crepuscular

active at dawn and dusk

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

insectivore

An animal that eats mainly insects or spiders.

internal fertilization

fertilization takes place within the female's body

island endemic

animals that live only on an island or set of islands.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

omnivore

an animal that mainly eats all kinds of things, including plants and animals

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

polymorphic

"many forms." A species is polymorphic if its individuals can be divided into two or more easily recognized groups, based on structure, color, or other similar characteristics. The term only applies when the distinct groups can be found in the same area; graded or clinal variation throughout the range of a species (e.g. a north-to-south decrease in size) is not polymorphism. Polymorphic characteristics may be inherited because the differences have a genetic basis, or they may be the result of environmental influences. We do not consider sexual differences (i.e. sexual dimorphism), seasonal changes (e.g. change in fur color), or age-related changes to be polymorphic. Polymorphism in a local population can be an adaptation to prevent density-dependent predation, where predators preferentially prey on the most common morph.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

solitary

lives alone

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

young precocial

young are relatively well-developed when born

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.

Ellerman, J. 1941. The Families and Genera of Living Rodents, vol. 2.. London: British Museum (Natural History).

Fleming, P., S. Nicolson. 2002. How important is the relationship between Protea humiflora (Proteaceae) and its non-flying mammal pollinators?. Oecologia, 132: 361–368.

Hubbard, C. 1972. Observations on the life histories and behavior of some small rodents from Tanzania. Zoologica Africana, 7(2): 419-449.

IUCN, 2004. "2004 IUCN Red List of Threatened Species" (On-line). Accessed June 26, 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. Molecular Phylogenetics and Evolution, 31: 256-276.

Janus, C., S. Holman. 1989. Development of sex differences in the response of spiny mouse pups to adult male odors. Physiology and Behavior, 46(5): 895-900.

Menge, J., J. Alberts. 2002. Sensory stimulation produced by parental behaviors during the delivery of precocial spiny mice (Acomys cahirinus). International Society for Developmental Psychobiology, 33rd Annual Meeting, 41 (1): 87.

Michaux, J., A. Reyes, F. Catzeflis. 2001. Evolutionary history of the most speciose mammals: molecular phylogeny of Muroid rodents. Molecular Biology and Evolution, 18(11): 2017-2031.

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. II. Baltimore and London: The Johns Hopkins University Press.

Porter, R., H. Doane. 1979. Responses of spiny mouse weanlings to conspecific chemical cues. Physiology and Behavior, 23: 75-78.

Shargal, E., L. Rath-Wolfson, N. Kronfeld, T. Dayan. 1999. Ecological and histological aspects of tail loss in spiny mice (Rodentia: Muridae, Acomys) with a review of its occurrence in rodents. Journal of Zoology, 249: 187-193.

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

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.