Biology:Rhim gazelle

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Short description: Species of mammal

Rhim gazelle
Slender-horned gazelle (Cincinnati Zoo).jpg
At the Cincinnati Zoo
CITES Appendix I (CITES)[2]
Scientific classification edit
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Bovidae
Subfamily: Antilopinae
Tribe: Antilopini
Genus: Gazella
Species:
G. leptoceros
Binomial name
Gazella leptoceros
(F. Cuvier, 1842)
Subspecies
  • G. l. leptoceros F. Cuvier, 1842
  • Thomas, 1894 G. l. loderi
Gazella leptoceros.png
Distribution map
Synonyms[3][4]
  • P. L. Sclater & Thomas, 1898 Fitzinger, 1869
  • Thomas, 1894 G. cuvieri
  • G. abuharab Fitzinger, 1869
  • G. typica G. loderi

The rhim gazelle or rhim (from Arabic غزال الريم) (Gazella leptoceros), also known as the slender-horned gazelle, African sand gazelle or Loder's gazelle, is a pale-coated gazelle with long slender horns and well adapted to desert life. It is considered an endangered species because fewer than 2500 are left in the wild. They are found in Algeria, Egypt, Tunisia[5] and Libya, and possibly Chad, Mali, Niger, and Sudan.

Name

According to Richard Lydekker, the name rhim is known in Algeria and Libya, while in Tunisian and Egyptian the animal is known as the ghazal abiad, "white gazelle", owing to its pale coat. The name rhim is cognate with and perhaps derived from the Hebrew term re'em found in the Bible, which may refer to an aurochs, oryx or perhaps a unicorn.[6]

Although described and named by Frédéric Cuvier in 1842, the rhim gazelle was rediscovered by Edmund Giles Loder later in the same century, hence the synonym Gazella loderi and the common name Loder's gazelle.[6]

Description

Skull
Horns of a rhim gazelle (below) and Dorcas gazelle (above)

Growing to a length of 101 to 116 cm (40 to 46 in), this is the palest of the gazelles, and well adapted to desert life in many ways. The upper parts are pale buff or cream and the limbs and under parts white or pale buff. The horns on the male are slender and slightly S-shaped; those of the female are even thinner, lighter and nearly straight. There are faint facial markings and an indistinct stripe along the side. The tail is brownish-black, about 15 cm (6 in) long, and contrasts with the pale rump.[7]

Distribution and habitat

The rhim gazelle is known from Algeria, Tunisia, Libya and Egypt. It has also been reported from Niger and Chad, but these sightings seem doubtful and its precise range is unclear. The rhim gazelle is found in isolated pockets across the central Sahara Desert. The extreme heat of this environment limits their feeding to the early morning and evening, and G. leptoceros gains most of its water requirements from dew and plant moisture, relying little on open water sources. The rhim gazelle is a nomadic species, moving across its desert range in search of vegetation, though it does not have a set migratory pattern. Its typical habitat is sand dunes and the depressions between them and other sandy areas, but also rocky areas.[7]

Physiological Adaptations

Rhim gazelles use a special type of temperature regulation called heterothermy to survive in this harsh desert climate. With heterothermy, animals no longer keep their body temperature within a narrow range.[8] Heterothermy in Rhim gazelles results in an increase in body temperature during the heat of the day that reduces the amount of evaporative cooling that gazelles would need to do in order to stay cool.[9] By reducing evaporative cooling, gazelles reduce energy expenditure and conserve body water. During cooler temperatures at night, the stored heat can be released, allowing the gazelles’ body temperature to decrease back to a normal physiological range.[9] Rhim gazelles maintain a normal skin temperature of about 35-°C in the summer and about 25-°C in the winter.[9] When heterothermy is employed, the gazelle experiences a body temperature increase of 5-20°C depending on seasonal conditions.[9]

Status

Endangered by the early 1970s, this species of gazelle was in serious decline. They were hunted firstly by mounted then by motorized hunters for sport, meat, or their horns, which were sold as ornaments in North African markets. The threats the animals face now include poaching, disturbance by humans and loss of suitable habitat. The International Union for Conservation of Nature estimates there may only be 300 to 600 mature individuals in the wild, and has rated their conservation status as "endangered".[1]

In philately

On February 1, 1987, the Libyan General Posts and Telecommunications Company, in cooperation with World Wide Fund for Nature, issued a set of four postage stamps illustrating Gazella leptoceros.[10]

References

  1. 1.0 1.1 IUCN SSC Antelope Specialist Group (2016). "Gazella leptoceros". IUCN Red List of Threatened Species 2016: e.T8972A50186909. doi:10.2305/IUCN.UK.2016-2.RLTS.T8972A50186909.en. https://www.iucnredlist.org/species/8972/50186909. Retrieved 13 November 2021. 
  2. "Appendices | CITES". https://cites.org/eng/app/appendices.php. 
  3. Beudels, Roseline C.; Devillers, Pierre (2013). "Gazella leptoceros Slender-horned Gazelle (Rhim Gazelle, Loder's Gazelle)". in Kingdon, Jonathan; Hoffmann, Michael. Hippopotamuses, Pigs, Deer, Giraffe and Bovids. Mammals of Africa. 6. London: Bloomsbury. pp. 352–355. 
  4. Grubb, P. (2005). "Order Artiodactyla". in Wilson, D.E.; Reeder, D.M. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. pp. 681–682. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.departments.bucknell.edu/biology/resources/msw3/browse.asp?id=14200001. 
  5. "Slender-horned Gazelle". https://www.whiteoakwildlife.org/wildlife/slender-horned-gazelle/. 
  6. 6.0 6.1 Richard Lydekker (1908), The Game Animals of Africa, London: Rowland Ward, pp. 254–55, https://archive.org/details/gameanimalsofafr00lyde .
  7. 7.0 7.1 Richard Hoath (2009). A Field Guide to the Mammals of Egypt. American University in Cairo Press. pp. 153–154. ISBN 978-977-416-254-1. https://books.google.com/books?id=agWfg6oEKKkC&pg=PA153. 
  8. Dittmann, Marie T.; Hebel, Christiana; Arif, Abdi; Kreuzer, Michael; Clauss, Marcus (2015-09-01). "Metabolic rates of three gazelle species (Nanger soemmerringii, Gazella gazella, Gazella spekei) adapted to arid habitats" (in en). Mammalian Biology 80 (5): 390–394. doi:10.1016/j.mambio.2015.05.008. ISSN 1616-5047. https://www.zora.uzh.ch/id/eprint/111449/9/MD_MammBiol_Gazelles_150518_mc.pdf. 
  9. 9.0 9.1 9.2 9.3 Hassan, Babor; Okab, Aly; Samara, Emad; Abdoun, Khalid; AL-Tayib, Omar; Al-Haidary, Ahmed (February 2014). "Adaptive Thermophysiological Adjustments of Gazelles to Survive Hot Summer Conditions". Pakistan Journal of Zoology 80: 390–394. 
  10. Libyan Stamps online

Further reading

External links

Wikidata ☰ Q838554 entry