Hyrax
The hyrax is so unlike other animals that it is
placed in a separate order (Hyracoidea) by itself. It is said to be
the elephant's nearest living relative. This is true to a certain
extent, but misleading since the relationship stems from a remote
ancestor common to hyraxes, sea cows (dugongs and manatees) and elephants.
These three are unlike other mammals, but they share various if disproportionate
physiological similarities in teeth, leg and foot bones, testes (that
do not descend into a scrotum) and other more obscure details.
Physical Characteristic
The hyrax, also called rock rabbit or dassie, is a small furry mammal.
It looks like a robust, oversized guinea pig, or a rabbit with rounded
ears and no tail. Hyraxes have stumpy toes with hooflike nails, four
toes on each front foot and three on each back foot. The longer, clawlike
nails on the inside toes of the back feet are used for grooming and
scratching. The bottoms of the feet have a rubbery texture to assist
in climbing steep rock surfaces and trees.
Of the three hyrax species, two are known as rock (or bush) hyrax
and the third as tree hyrax. In the field it is sometimes difficult
to differentiate among them.
The rock hyrax has the widest distribution in East Africa. Its
coat is yellowish or grayish-brown, and the dorsal spot (a bare
scent gland on the back covered with longer hair) is covered with
black or yellow hair. Its head is more rounded than other types
of hyraxes, and the nose is blunt.
The yellow-spotted hyrax, or rock rabbit, is smaller in size and
has a more pointed, rodentlike nose. Generally it has a conspicuous
white patch above the eye, and its dorsal spot is whitish or yellowish.
It is sometimes seen in company of other types of hyrax, but species
do not interbreed.
Tree hyraxes, unsurprisingly, spend a lot of time in trees. In
some areas they are hunted for their thick, soft, long hair. They
have a white or yellow dorsal spot.
Habitat
Hyraxes are very adaptable. In East Africa they
live at sea level and up to altitudes of over 14,000 feet and in habitats
ranging from dry savanna to dense rainforest to cold Afro-alpine moorland.
Behavior
Rock hyraxes do not dig burrows. They live in colonies
of 50 or so in natural crevices of rocks or bolders. They regularly
use "latrines" and in areas they inhabit, conspicuous white
deposits from their urine form on rock faces. They are active in the
daytime and can be seen feeding or sunning themselves near the entrances
to their shelters.
Hyrax vocalizations include twitters, growls, whistles and shrieks.
One group will answer the contact calls of another group. The raucous
nocturnal shriek of the tree hyrax is most impressive, starting
as a squeak or whistle, then rising to a piglike squeal and finally
to a child's scream. Hyraxes do most of their screaming as they
ascend or descend trees during the night.
The tree hyrax is nocturnal and not as social as the rock hyraxes.
They are often found in pairs and do not form much larger groups.
Although naturally shy, hyraxes in captivity become quite tame.
Their habits of using latrines and eating a variety of vegetative
material make them easy to keep. They have been recorded as living
as long 12 years.
Diet
Rock hyraxes spend several hours sunbathing in the
mornings, followed by short excursions to feed. They eat quickly with
the family group facing out from a circle to watch for potential predators,
feeding on grasses, herbage, leaves, fruit, insects, lizards and birds'
eggs. After biting off a mouthful of grass or leaves, the hyrax looks
up and cautiously checks the vicinity. If the territorial male gives
the shrill shriek of alarm, the hyraxes jump or scuttle to cover where
they remain frozen, without moving, until the danger has passed. They
can go a long time without water, apparently obtaining enough moisture
from their food. Tree hyraxes feed on leaves and fruits.
Caring for the Young
Rock hyraxes bear two or three young, which are
so fully developed they can run and jump about an hour after birth.
Although suckled until 3 months old, the young begin to eat vegetation
by their second day. The young of all females in a family group often
gather in a nursery group. The tree hyrax has fewer young (one or
two at the most) than rock hyraxes, but they have many similar behaviors
traits, such as always defecating and urinating on the same spot.
Predators
Hyraxes are preyed upon by leopards, pythons, large
birds, caracals, servals and civets. They protect themselves from
smaller predators by biting, but escaping to hiding places among the
rocks is their best defense.
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