Therock hyrax (/ˈhaɪ.ræks/;Procavia capensis), also calleddassie,Cape hyrax,rock rabbit, orconey (in early English Bible translations[3]), is a medium-sized terrestrial mammal native to Africa and theMiddle East. Commonly referred to inSouth Africa as the dassie (/ˈdæsi/;Afrikaans:klipdassie),[4] it is one of the five living species of theorderHyracoidea, and the only one in the genusProcavia.[1]Rock hyraxes weigh 4–5 kg (8.8–11.0 lb) and have short ears.[4]
Rock hyraxes are found at elevations up to 4,200 m (13,800 ft) above sea level[5] in habitats with rock crevices, allowing them to escape from predators.[5][6] They are the onlyextant terrestrialafrotherians in the Middle East.[note 1] Hyraxes typically live in groups of 10–80 animals, andforage as a group. They have been reported to use sentries to warn of the approach ofpredators. Having incompletethermoregulation, they are most active in the morning and evening, although their activity pattern varies substantially with season and climate.
Over most of its range, the rock hyrax is not endangered, and in some areas is considered a minor pest.
Along with other hyrax species and thesirenians, this species is the most closely related to theelephant.[7] An unrelated,convergently evolved mammal of similar habits and appearance is therock cavy of Brazil.
Rock hyraxes are squat and heavily built, with adults reaching a length of 50 cm (20 in) and weighing around 4 kg (8.8 lb), with a slightsexual dimorphism, males being about 10% heavier than females. Their fur is thick and grey-brown, although this varies strongly between different environments, from dark brown in wetter habitats, to light gray in desert-living individuals.[8] Hyrax size (as measured byskull length andhumerus diameter) is correlated toprecipitation, probably because of the effect on preferred hyrax forage.[9]
Prominent in and apparently unique to hyraxes is the dorsal gland, which excretes an odour used for social communication andterritorial marking. The gland is most clearly visible in dominant males.[10]
The rock hyrax has a pointed head, short neck, and rounded ears. It has long, black whiskers on its muzzle.[11] The rock hyrax has a prominent pair of long, pointedtusk-like upperincisors, which are reminiscent of the elephant, to which the hyrax is distantly related. The fore feet areplantigrade, and the hind feet are semi-digitigrade. The soles of the feet have large, soft pads that are kept moist with sweat-like secretions. In males, thetestes are permanently abdominal, another anatomical feature that hyraxes share with elephants and sirenians.[10]
Thermoregulation in rock hyraxes has been subject to much research, as their body temperature varies with adiurnal rhythm. Animals kept in constant environmental conditions also display such variation,[10] and this internal mechanism may be related to water balance regulation.[12]
in Namibia
Skull of a rock hyrax
The dorsal gland visible as a patch of fur with lighter colour
The shade of their pelts varies individually and regionally.[14] In particular, the dorsal patches (present in both sexes) of the central populations are very variable, ranging from yellow to black, or flecked. In outlying populations, these are more constant in colour, black inP. c. capensis, cream inP. c. welwitschii, and orange inP. c. ruficeps.[14] A larger, longer-haired population is abundant in themoraines in the alpine zone ofMount Kenya.[15][16]
Rock hyraxes build dwelling holes in any type of rock with suitable cavities, such as sedimentary rocks and soil.[17]In Mount Kenya, rock hyraxes live in colonies comprising an adult male, several adult females, and immatures. They are active during the day, and sometimes during moonlit nights.[18] The dominant male defends and watches over the group. The male also marks his territory.
Hyraxes feed on a wide variety of plant species, includingLobelia[18] andbroad-leafed plants.[23] They also have been reported to eat insects and grubs.[11] They forage for food up to about 50 m from their refuge, usually feeding as a group and with one or more acting as sentries from a prominent lookout position. On the approach of danger, the sentries give an alarm call, and the animals quickly retreat to their refuge.[24]
They are able to go for many days without water due to the moisture they obtain through their food, but quickly dehydrate under direct sunlight.[25] Despite their seemingly clumsy build, they are able to climb trees (although not as readily asHeterohyrax), and readily enter residential gardens to feed on the leaves ofcitrus and other trees.
The rock hyrax also makes a loud, grunting sound while moving its jaws as if chewing, and this behaviour may be a sign ofaggression. Some authors have proposed that observation of this behavior by ancientIsraelites gave rise to the misconception given inLeviticus 11:4–8 that the hyrax chews the cud,[26] but the hyrax is not aruminant.[10]
Rock hyraxes give birth to two to four young after agestation period of 6–7 months (long, for their size). The young are well developed at birth with fully opened eyes and completepelage. Young can ingest solid food after two weeks and are weaned at 10 weeks. After 16 months, they become sexually mature, they reach adult size at 3 years, and they typically live about 10 years.[10] During seasonal changes, the weight of the male reproductive organs (testes, seminal vesicles) changes due to sexual activity. Between May and January inCape Province, South Africa, the males are inactive sexually. From February onward, the weight of these organs increases dramatically and the males are able to copulate.[27]
Hyraxes that live in more "egalitarian" groups, in which social associations are spread more evenly among group members, survive longer.[28] In addition, hyraxes are the first nonhuman species in whichstructural balance was described. They follow "the friend of my friend is my friend" rule, and avoid unbalanced social configurations.[29] The balance of social interactions within a group is positively correlated to individual longevity, meaning that "it is not the number or strength of associations that an adult individual has (i.e. centrality) that is important, but the overall configuration of social relationships within the group."[30] The reason for such a balanced group configuration, rather than one that is centrally dominated by a few individual hyraxes, was suggested to have to do with the fact that information flow to all members is important in a fragmented habitat as that of the hyrax, making a dominance hierarchy a liability for the survival of the group at large.[30]
Captive rock hyraxes make more than 20 different noises and vocal signals.[18] The most familiar one is a high trill, given in response to perceived danger.[11] Rock hyrax calls can provide important biological information, such as size, age, social status, body weight, condition, and hormonal state of the caller, as determined by measuring their call length, patterns, complexity, and frequency.[31] More recently, researchers have found rich syntactic structure and geographical variations in the calls of rock hyraxes, a first in the vocalization of mammalian taxa other than primates, cetaceans, and bats.[32] Higher-ranked males tend to sing more often, and the energetic cost of singing is relatively low.[33] A recent study found that snorts, a rare aspect of male hyrax songs, play an important signalling role as well, with increasing snort harshness being associated with "the progression of inner excitement or aggression". It is also positively associated with the singing animal's social status and testosterone levels.[34] Singing has also been shown to be a marker of an individual hyrax's unique identity, where identity is expressed by unique vocal signatures "that are not condition dependent and are stable over years in singers that did not alter their spatial position."[35]
The rock hyrax spends roughly 95% of its time resting.[10] During this time, it can often be seen basking in the sun, which sometimes involves "heaping", where several animals pile on top of each other. This is thought to be an element of its complexthermoregulation.[36]
Male hyraxes have been categorised into four classes: territorial, peripheral, early dispersers, and late dispersers. The territorial males are dominant. Peripheral males are more solitary and sometimes take over a group when the dominant male is missing. Early-dispersing males are juveniles that leave the birth site around 16 to 24 months of age. Late dispersers are also juvenile males, but they leave the birth site much later, around 30 or more months of age.[37]
The species is known asklipdas inAfrikaans (etymology: rock + badger),[citation needed] while most people just call them "dassies" (the plural of dassie) or "rock rabbits" in South Africa. TheSwahili names for them arepimbi,pelele, andwibari, though the latter two names are nowadays reserved for thetree hyraxes.[38]This species has many subspecies, many of which are also known as rock or Cape hyrax, although the former usually refers to African varieties.
InArabic, the rock hyrax is calledالوبر الصخري (alwabr alsakhri) orطبسون (tabsoun). InClassical Hebrew, the rock hyrax is calledשָׁפָן (shafan).[39] In Modern Hebrew, this wordcolloquially refers to the rabbit, whileשפן סלע (shafan sela) is used for hyrax.[26] According toGerald Durrell, local people inBafut, Cameroon, call the rock hyrax then'eer.[40]
Rock hyraxes produce large quantities ofhyraceum, a sticky mass of dung and urine that has been employed as a South African folk remedy in the treatment of several medicaldisorders, includingepilepsy andconvulsions.[41] Hyraceum is now being used by perfumers, who tincture it in alcohol to yield a natural animalmusk.[42]
The rock hyrax is classified astreif (not kosher; unclean) according tokashrut – Jewish food hygiene rules – due to statements in theTorah:"And the coney, because he cheweth the cud, but divideth not the hoof; he is unclean unto you" (Leviticus 11:5).[43] Hyraxes are also mentioned in Proverbs 30:26 as one of a number of remarkable animals for being small but exceedingly wise, in this case because "the conies are a people not mighty, yet they make their homes in the cliffs".[44]
InJoy Adamson's books and the filmBorn Free, a rock hyrax called Pati-Pati was her companion for six years beforeElsa and her siblings came along; Pati-Pati reportedly took the role of nanny and watched over them with great care.[45]
The 2013 animated filmKhumba features a number of rock hyraxes that sacrifice one of their own to a whiteVerreaux's eagle.
^Meltzer, A. (1973)Heat balance and water economy of the rock hyrax (Procavia capensis syriaca Schreber 1784). Unpubl. Ph.D. dissert., Tel-Aviv Univ., Israel, 135 pp.
^Sale, J. B. (1966). "The habitat of the rock hyrax".Journal of the East African Natural History Society.25:205–214.
^abcYoung, T. P., & Matthew, R. E. (1993). Alpine vertebrates of Mount Kenya, with particular notes on the rock hyrax. East Africa Natural History Society.
^Turner, M. I. M.; Watson, R. M. (1965). "An introductory study on the ecology of hyrax (Dendrohyrax brucei andProcavia johnstoni) in the Serengeti National Park".African Journal of Ecology.3 (1):49–60.Bibcode:1965AfJEc...3...49T.doi:10.1111/j.1365-2028.1965.tb00737.x.
^Margolis, E. (2008). "Dietary composition of the wolfCanis lupus in the Ein Gedi area according to analysis of their droppings (in Hebrew)".Proceedings of the 45th Meeting of the Israel Zoological Society.
^Ilany, A.; Barocas, A.; Koren, L.; Kam, M.; Geffen, E. (2013). "Structural balance in the social networks of a wild mammal".Animal Behaviour.85 (6):1397–1405.doi:10.1016/j.anbehav.2013.03.032.S2CID28628927.
^Clines, David J.A., ed. (2011).The Dictionary of Classical Hebrew. Vol. 8. Sheffield, England: Sheffield Academic Press. p. 544.ISBN978-1-907534-46-1.
^Durrell, G. (1954).The Bafut Beagles. Rupert Hart-Davies.
^Olsen, A., Prinsloo, L. C., Scott, L., Jägera, A, K. (2008) "Hyraceum, the fossilized metabolic product of rock hyraxes (Procavia capensis), shows GABA-benzodiazepine receptor affinity". South African Journal of Science 103.