Acomys cahirinusCairo spiny mouse

Geographic Range

Cairo spiny mice are found throughout northern African, from the western Sahara in Mauritania and Morocco east to Egypt, Ethiopia, Eritrea, and Sudan. ("Egyptian Spiny Mouse", 2004)

Habitat

Cairo spiny mice tend to live in arid, rocky habitats, such as rocky canyons, near cliffs, or near human habitation where they use crevices in buildings. They may also be found in gravelly washes, but are not generally found in sandy areas. They are found mostly on the ground and in burrows, but they occasionally climb. Generally, these spiny mice avoid altitudes above 1500 meters. ("Egyptian Spiny Mouse", 2004; "Mice", 2008)

  • Range elevation
    1500 (high) m
    4921.26 (high) ft

Physical Description

Cairo spiny mice are defined by gray-brown to sandy colored, spiny hairs that cover their backs. These hairs resemble the spines of hedgehogs. The underside of these mice is characteristically white while the upper body is brown, grey, or beige colored. These mice have a body length of 7 to 17 cm, weigh between 30 and 70 g. They are characterized by a scaly, hairless tail that varies in length from 5 to 12 cm. ("Egyptian Spiny Mouse", 2004; "Egyptian Spiny Mouse", 2012)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    30 to 70 g
    1.06 to 2.47 oz
  • Range length
    7 to 17 cm
    2.76 to 6.69 in

Reproduction

There is little specific information on the mating system of Cairo spiny mice in the literature. However, social groups seem to be made up of a dominant male and a group of females, suggesting polgyny. Females have help from conspecifics in raising their young. (Medger, et al., 2010)

The main breeding season of Cairo spiny mice is between September and January, while females are reproductively inactive from February through to August. However, other sources suggest that breeding may occur year-round. The main breeding season corresponds with the onset of the rainy season, which generally begins around September and ends in April. The increase in rain and food availability is perhaps the most important factor for reproduction in female Cairo spiny mice. This species reaches sexual maturity in about 2 months. Acomys cahirinus have a gestation period of 5 to 6 weeks, about 2 weeks longer than typical in similarly sized mice, which means that the young are extremely well developed at birth. Since they live in small groups (see Behavior below), during the birthing process, females tend to help each other by chewing through the umbilical cord and licking the placenta. The young are born with enough hair to thermoregulate independently without the help of a mother and also open their eyes at birth or within the first couple days. These mice tend to produce approximately 1 to 5 offspring in a litter and in just a few days after their birth, infant mice are treated as common children where they are nursed by every mother in the group and accepted everywhere. Incredibly enough, the new mother is fertile once again the evening of the same day she gives birth. ("Egyptian Spiny Mouse", 2004; "Mice", 2008; Medger, et al., 2010)

  • Breeding interval
    Cairo spiny mice breed 3 to 4 times during their breeding season.
  • Breeding season
    Acomys cahirinus breeds from September to January.
  • Range number of offspring
    1 to 5
  • Range gestation period
    5 to 6 weeks
  • Range age at sexual or reproductive maturity (female)
    2 (low) months
  • Range age at sexual or reproductive maturity (male)
    2 (low) months

Since Cairo spiny mice live in groups and care for young cooperatively, the mother is not solely responsible for parental care. Additionally, the advanced development of the young at birth and their early independence mean that the duration of parental investment is relatively short. By the third day after birth, young mice are already exploring and investigating their surroundings, and by the age of 2 months they are sexually mature. ("Egyptian Spiny Mouse", 2004)

  • Parental Investment
  • precocial
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

In captivity, Cairo spiny mice live up to 4 years. No information is currently available for the lifespan of this species in the wild. ("Egyptian Spiny Mouse", 2012)

  • Range lifespan
    Status: captivity
    4 (high) years

Behavior

Cairo spiny mice are very social animals that tend to congregate into small groups. Each group has one dominant male who will fight if he is challenged by others males within the group. The 8 different species of spiny mice in the genus Acomys have overlapping geographic ranges. However, they all forage at different times of the day, avoiding competition. For example, Acomys cahirinus is nocturnal while Acomys russatus is diurnal. ("Egyptian Spiny Mouse", 2004; Jones and Dayan, 2000)

Home Range

There is no information on home range in Cairo spiny mice in the literature.

Communication and Perception

Cairo spiny mice seem to use chemical signals in order to communicate with each other to warn others of dangerous predators; however, there is little information regarding specific chemicals produced by this species. This species most likely also perceives the environment through their other visual, tactile and acoustic senses. ("Egyptian Spiny Mouse", 2004)

Food Habits

Cairo spiny mice are omnivorous and opportunistic, eating seeds, fruits, dried plants, spiders, small insects, and even snails. This species has also been known to feed on dried Egyptian mummies. In populations that live in close contact with humans, they are known to feed on grains, stored food, and human crops. ("Egyptian Spiny Mouse", 2004; "Mice", 2008)

  • Animal Foods
  • carrion
  • insects
  • terrestrial non-insect arthropods
  • mollusks
  • Plant Foods
  • leaves
  • seeds, grains, and nuts
  • fruit

Predation

The main predators of Cairo spiny mice are Blanford's foxes (Vulpes cana). In order to avoid this predator, Acomys cahirinus uses chemical signals to communicate with other mice in their group to warn them that danger is near. Though there are no published accounts of other predators, it is likely that the Egyptian spiny mouse are preyed on by a variety of species, such as nocturnal raptors and snakes. (Jones and Dayan, 2000)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Cairo spiny mice serve as a food source for Vulpes cana. They also are parasitized by ticks and fleas that are carriers for diseases such as typhus, Salmonella food poisoning and spotted fever. ("Mice", 2008; Jones and Dayan, 2000)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

Cairo spiny mice have been widely used as laboratory animals for research in the areas of medicine and biology, including genetics, virology, pharmaceutical development, and cancer research. ("Mice", 2008)

  • Positive Impacts
  • research and education

Economic Importance for Humans: Negative

Cairo spiny mice have been destroying crops near human habitation for thousands of years and they have been known to spread deadly diseases such as typhus, spotted fever, and Salmonella food poisoning ("Mice", 2008)

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

Conservation Status

Cairo spiny mice are not currently considered threatened.

Other Comments

Cairo spiny mice were first discovered in Egypt.

Contributors

Clara Regula (author), Sierra College, Jennifer Skillen (editor), Sierra College, Tanya Dewey (editor), 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

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.

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

cooperative breeder

helpers provide assistance in raising young that are not their own

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

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.

female parental care

parental care is carried out by females

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).

motile

having the capacity to move from one place to another.

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

pheromones

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

polygynous

having more than one female as a mate at one time

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

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.

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 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.

young precocial

young are relatively well-developed when born

References

2004. Egyptian Spiny Mouse. Pp. 259 in Grzimek's Animal Life Encyclopedia, Vol. 16, 2nd Edition. Detroit: Gale. Accessed March 05, 2012 at http://go.galegroup.com.proxy.sierracollege.edu/ps/marklist.do?actionCmd=GET_MARK_LIST&ts=1330937515639&inPS=true&prodId=GVRL&userGroupName=rock89639.

2012. "Egyptian Spiny Mouse" (On-line). World Association of Zoos and Aquariums. Accessed March 11, 2012 at http://www.waza.org/en/zoo/visit-the-zoo/rodents-and-hares/acomys-cahirinus.

2008. Mice. Pp. 2743 in The Gale Encyclopedia of Science, Vol. 1, 4 Edition. Detroit: The Gale Group Inc.. Accessed March 06, 2012 at http://go.galegroup.com.proxy.sierracollege.edu/ps/pdfViewer?sgHitCountType=None&sort=RELEVANCE&docType=GALE&tabID=T003&prodId=GVRL&searchId=R6&resultListType=RESULT_LIST&searchType=BasicSearchForm&contentSegment=&currentPosition=3&inPS=true&userGroupName=rock89639&docId=GALE%7CCX2830101475&contentSet=GALE%7CCX2830101475&.

Jones, M., T. Dayan. 2000. Foraging Behavior and Microhabitat Use by Spiny Mice, Acomys cahirinus and A. russatus, in the Presence of Blanford's Fox (Vulpes cana) Odor. Journal of Chemical Ecology, 26/2: 456.

Medger, K., C. Chimimba, N. Bennett. 2010. Seasonal Reproduction in the Female Spiny Mouse from South Africa. Journal of Zoology, 282/3: 163-170.