Verreaux's Sifaka
Encyclopedia
Verreaux's sifaka or white sifaka, is a medium sized primate
in one of the lemur
families, Indriidae
. It lives in Madagascar
and can be found in a variety of habitats from rainforest to western Madagascar dry deciduous forests
and dry and spiny forests. The fur is thick and silky and generally white with brown on the sides, top of the head, and on the arms. Like all sifaka
s, it has a long tail that it uses as a balance when leaping from tree to tree. However, its body is so highly adapted to an arboreal existence that on the ground its only means of locomotion is hopping. The species lives in small troops which they forage for food with.
There are four sub species of this kind of lemur. There are many things unknown about Verreaux's sifaka, so their life span in the wild has not been approximated, but in captivity they generally live to become up to 18 years old.
Verreaux's sifaka has a relatively low, flat braincase. The face is broader than that of most other Indriids, but its snout is reduced. This species of sifaka is also distinguished by its unique dentition. Its dental formula
is . The upper incisors are very small and are slightly angled inward towards the gap between I1 and I2. In the mandible, Verreaux's sifaka displays the stresirhine characteristic: the toothcomb. Formed by the procumbent lower incisor and canine, the toothcomb projects past the front margin of the mouth. P. verreauxi also presents the high, shearing molar crests of a folivore, helping to shread the leaves, fruit, and flowers that it eats. Postcranially, Verreaux's Sifaka has a low intermembral index that ranges from 63-66. It has a broader ribcage than most other prosimians and has many lumbar vertebrae lending it a lot of flexibility. The pelvic is high and narrow and the acetabulum is relatively shallow, also allowing for greater flexibility. Like other Indriids, P. verreauxi has a short calcaneus, pointed nails, and slightly webbed hands and feet.
for food in the troop it lives in, primarily in the morning and late afternoon, so they can rest during the hottest part of the day. They are herbivores and leaves, fruit, bark and flowers are typical components of the diet. However, they are mostly folivorous (leaves represent the majority of the diet over the year, especially in the dry season) and they seem to choose food items on the ground of quality (lower tannin content) than on the ground of availability. .
.
Females use anogenital secretion mainly for territory demarcation whereas males seem to use specialized secretions (via anogenital and throat glands) more for sexual "advertisement" than for territorial purposes .
Over the year males and females engage in a biological market, exchanging grooming for grooming (interchange) during the non mating period, and grooming ("offered" by males) for reproductive opportunities (sexual access "offered" by females) during the mating period . Recently, it has been discovered that sifaka dyads often engage in post-conflict reunions after aggressive episodes: reconciliation occurs more frequently when food is not involved and for low intensity aggressions.. In this species play behavior persists into adulthood where it is used, especially by stranger males during the mating period, as an ice-breaking mechanism to reduce xenophobia
They are diurnal and arboreal, and engage in sunbathing with outstretched arms and legs. Verreaux's sifaka move through the trees by clinging and leaping between vertical supports. They are capable of making remarkable leaps through the trees - distances of 9-10m are not uncommon. On the ground, they hop bipedally.
period of 130 days, between June and August. For the first 6–8 weeks, the infant clings to the mother's stomach, but for the following 19 weeks, it clings to her back.
In the small spiny forest fragments of South Madagascar, sifaka abundance appears to be influenced by the proportion of large trees (diameter at breast height >=5cm) and by the abundance of the plant species Allouadia procera , a key species of the spiny forest habitat .
Primate
A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...
in one of the lemur
Lemur
Lemurs are a clade of strepsirrhine primates endemic to the island of Madagascar. They are named after the lemures of Roman mythology due to the ghostly vocalizations, reflective eyes, and the nocturnal habits of some species...
families, Indriidae
Indriidae
The Indriidae are a family of strepsirrhine primates. They are medium to large sized lemurs with only four teeth in the toothcomb instead of the usual six...
. It lives in Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
and can be found in a variety of habitats from rainforest to western Madagascar dry deciduous forests
Madagascar dry deciduous forests
The Madagascar dry deciduous forests represent a tropical dry forest ecoregion generally situated in the western part of Madagascar. The area has high numbers of endemic plant and animal species but has suffered large-scale clearance for agriculture...
and dry and spiny forests. The fur is thick and silky and generally white with brown on the sides, top of the head, and on the arms. Like all sifaka
Sifaka
Sifakas are a genus of lemur from the family Indriidae within the order Primates. Their name of the family is an onomatopoeia of their characteristic "shi-fak" alarm call. Like all lemurs, they are found only on the island of Madagascar...
s, it has a long tail that it uses as a balance when leaping from tree to tree. However, its body is so highly adapted to an arboreal existence that on the ground its only means of locomotion is hopping. The species lives in small troops which they forage for food with.
There are four sub species of this kind of lemur. There are many things unknown about Verreaux's sifaka, so their life span in the wild has not been approximated, but in captivity they generally live to become up to 18 years old.
Anatomy
In adulthood the full head and body length is between 42 and 45 cm (16.5 and 17.7 in). The tail of a fully grown Verreaux's sifaka grows to be between 56 and 60 cm (22 and 23.6 in) long. In terms of weight, adult females reach 3.4 kg (7.5 lb) on average, and adult males 3.6 kg (7.9 lb).Verreaux's sifaka has a relatively low, flat braincase. The face is broader than that of most other Indriids, but its snout is reduced. This species of sifaka is also distinguished by its unique dentition. Its dental formula
Dentition
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, the characteristic arrangement, kind, and number of teeth in a given species at a given age...
is . The upper incisors are very small and are slightly angled inward towards the gap between I1 and I2. In the mandible, Verreaux's sifaka displays the stresirhine characteristic: the toothcomb. Formed by the procumbent lower incisor and canine, the toothcomb projects past the front margin of the mouth. P. verreauxi also presents the high, shearing molar crests of a folivore, helping to shread the leaves, fruit, and flowers that it eats. Postcranially, Verreaux's Sifaka has a low intermembral index that ranges from 63-66. It has a broader ribcage than most other prosimians and has many lumbar vertebrae lending it a lot of flexibility. The pelvic is high and narrow and the acetabulum is relatively shallow, also allowing for greater flexibility. Like other Indriids, P. verreauxi has a short calcaneus, pointed nails, and slightly webbed hands and feet.
Diet
Verreaux's sifaka forageForage
Forage is plant material eaten by grazing livestock.Historically the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially...
for food in the troop it lives in, primarily in the morning and late afternoon, so they can rest during the hottest part of the day. They are herbivores and leaves, fruit, bark and flowers are typical components of the diet. However, they are mostly folivorous (leaves represent the majority of the diet over the year, especially in the dry season) and they seem to choose food items on the ground of quality (lower tannin content) than on the ground of availability. .
Behaviour
They live in family groups, or troops, of 2-12, which may be just one male and female or multimale-multifemale. Group and population sex ratio can be more or less skewed toward males . Many groups seem to be effectively harem groups with a single dominant male unrelated with resident female(s) . They have a home range of 2.8.5ha, and although they are territorial, it is the food source they will defend rather than the territory's boundaries, as often boundaries overlap. Females are dominant over males, forming a society using MatriarchyMatriarchy
A matriarchy is a society in which females, especially mothers, have the central roles of political leadership and moral authority. It is also sometimes called a gynocratic or gynocentric society....
.
Females use anogenital secretion mainly for territory demarcation whereas males seem to use specialized secretions (via anogenital and throat glands) more for sexual "advertisement" than for territorial purposes .
Over the year males and females engage in a biological market, exchanging grooming for grooming (interchange) during the non mating period, and grooming ("offered" by males) for reproductive opportunities (sexual access "offered" by females) during the mating period . Recently, it has been discovered that sifaka dyads often engage in post-conflict reunions after aggressive episodes: reconciliation occurs more frequently when food is not involved and for low intensity aggressions.. In this species play behavior persists into adulthood where it is used, especially by stranger males during the mating period, as an ice-breaking mechanism to reduce xenophobia
They are diurnal and arboreal, and engage in sunbathing with outstretched arms and legs. Verreaux's sifaka move through the trees by clinging and leaping between vertical supports. They are capable of making remarkable leaps through the trees - distances of 9-10m are not uncommon. On the ground, they hop bipedally.
Reproduction
Females give birth to one infant after a gestationGestation
Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during pregnancy can have one or more gestations at the same time ....
period of 130 days, between June and August. For the first 6–8 weeks, the infant clings to the mother's stomach, but for the following 19 weeks, it clings to her back.
Ecology and Conservation status
Currently this species is considered to be Vulnerable by the IUCN.In the small spiny forest fragments of South Madagascar, sifaka abundance appears to be influenced by the proportion of large trees (diameter at breast height >=5cm) and by the abundance of the plant species Allouadia procera , a key species of the spiny forest habitat .