Little gerbil

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Little gerbil
Little gerbil (Jaculus jaculus)

Little gerbil ( Jaculus jaculus )

Systematics
Subclass : Higher mammals (Eutheria)
Superordinate : Euarchontoglires
Order : Rodents (Rodentia)
Family : Jerboa (Dipodidae)
Genre : Gerbils ( jaculus )
Type : Little gerbil
Scientific name
Jaculus jaculus
( Carl von Linné , 1758)

The little gerbil ( Jaculus jaculus ) is a species of mammal belonging to the genus of the gerbils ( Jaculus ) and the family of the jerboa (Dipodidae).

In the Red List of Endangered Species of the International Union for Conservation of Nature ( IUCN) the little gerbil is listed as not endangered ( least concern ).

features

Skeleton of Jaculus spec.

With a head body length of 9.5 to 11 cm, a tail length of 15 to 25 cm and a weight of 43 to 73 g, the small gerbil is the smallest species of the genus of the gerbil . The females show low sexual dimorphism by being slightly heavier than the males. The rear foot length is about 50 to 75 mm. In total, each foot has three toes. There are small, bristly hairs on the soles that prevent them from sinking into the sand. The fibula , thigh bone and the middle metatarsal bones are enormously elongated, as is the case with many jerboa, just like the outer rays are reduced and the inner rays are particularly strong, which enables kangaroo-like hopping. This energy-efficient type of locomotion compensates for the energetic resources required for the distance to be covered during the day, which is necessary to find the food. The eyes are very large in adaptation to the nocturnal way of life. In addition to hearing, the large ears are used for heat regulation. Depending on the area of ​​distribution, the fur is light brown, beige or orange on top with or without a grayish admixture and white on the underside. The tail serves as a support when sitting upright and has a black and white tassel on the distal third.

Distribution and habitat

The distribution area of ​​the small jerboa is in parts of North Africa and the Middle East and extends from Mauritania, on the northern edge of the Sahara to Algeria, Libya, Egypt and Sudan, via Jordan, Syria, Saudi Arabia, Oman, Yemen to the northeast of Iran. An isolated occurrence lies like an island between Mali and Burkina Faso, in Niger and in Eritrea. Small gerbils could be detected up to a height of 1500 m. Different habitat types have been described, including deserts and semi-deserts, which are characterized by a low density of vegetation.

Way of life and food

Track of a gerbil in the Akakus Mountains

Small gerbils are nocturnal and live solitary. During the day they sleep in well-padded buildings they have built or taken over, which are closed with nesting material after entering and are about 1.2 m deep. They also have a storage chamber for feed, which is consumed in times when there is little food. Due to the enormous jumping power, speeds of up to 45 km / h can be achieved, a single jump covers a distance of up to 3 m. After leaving the burrow at night, paths of up to 12 km are covered, with obstacles being skilfully avoided by striking real hooks and the tail compensating for these movements. The diet consists of grasses, seeds, greens and insects. The entire fluid requirement is absorbed through food. The activity strongly depends on the temperature and can be completely absent for a short time. It is unclear whether the animals will hibernate during winter as there have been few observations.

Reproduction and Life Expectancy

In Egypt, the breeding season was documented from June to July and in Sudan from October to August. Mating is initiated by the male chasing the female and signaled by making contact via the mouth. A female can give birth twice a year and withdraws to nest building before giving birth. After a gestation period of around 25 days, 3 to 6 cubs are born. At birth, the young are completely naked and their eyes are closed. At birth the weight is about 2 g, the length of the head body is about 15 mm, the length of the hind foot is about 4 mm and the tail is about 25 mm. After about 6 weeks the young animals slowly become independent and are weaned at about 8 weeks. The maximum age in captivity is 7 years and 3 months.

threat

In some areas, such as Yemen and the Negev desert, the lesser gerbil is hunted for human consumption and is a target of hunting . However, due to their large distribution area, they are not considered to be particularly threatened despite their occurrence in some places only on an island.

Naming

The generic name Jaculus is derived from the Latin word "iaculum" for spear and can be traced back to the enormous jumping activity of the gerbils in the sense of a thrown spear. In Arabic-speaking countries the little gerbil is called "yerboua" or "jerboua" ( Arabic یربوع, DMG yarbūʿ ).

literature

  • Ronald M. Nowak: Walker's Mammals of the World. 2 volumes. 6th edition. Johns Hopkins University Press, Baltimore MD et al. 1999, ISBN 0-8018-5789-9 .
  • Don E. Wilson , DeeAnn M. Reeder (Eds.): Mammal Species of the World. A Taxonomic and Geographic Reference. 2nd edition. Smithsonian Institution Press, Washington DC et al. 1993, ISBN 1-56098-217-9 .

Web links

Commons : Little Jerboa ( Jaculus jaculus )  - Collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d Jaculus jaculus in the Red List of Endangered Species of the IUCN 2008. Posted by: Amori, G., Hutterer, R., Kryštufek, B., Yigit, N., Mitsain, G., Palomo, LJ & Aulagnier , S., 2008. Retrieved September 8, 2012
  2. ↑ a b c d e f g h i Jaculus jaculus in the Animal Diversity Web of the University of Michigan Museum of Zoology. Retrieved September 8, 2012
  3. ^ Richard Weigl: Longevity of Mammals in Captivity. From the Living Collections of the World. A List of Mammalian Longevity in Captivity (= Kleine Senckenberg series. Vol. 48). Schweizerbart, Stuttgart 2005, ISBN 3-510-61379-1 .
  4. ↑ Mazin B. Qumsiyeh: Mammals of the Holy Land. Texas Tech University Press, Lubbock TX 1996, ISBN 0-89672-364-X .