Spider Monkeys
Spider Monkeys
The appearance of the spider monkey species
Spider monkeys are slender, medium-sized monkeys with long limbs and very long tails. They live in trees, rarely coming down to the jungle floor. They are very adept at moving around in trees with the help of their prehensile tails; “prehensile” is a term that means their tails are well adapted for holding on to objects. These monkeys inhabit a territory ranging from southern Mexico to northern Argentina.
These New World monkeys are classified in the family Atelidae. Within the Atelidae family, there are two subfamilies, consisting of 5 genera and 22-24 species. Spider monkeys are in the subfamily called Atelinae and thegenus Ateles, meaning “imperfect” because these monkeys have very small or absent thumbs. There are six species of spider monkeys: 1. Central American spider monkey (Ateles geoffroyi ); 2. brown-headed spider monkey (A. fusciceps ); 3. white-bellied spider monkey (A. belzebuth ); 4. black spider monkey (A. paniscus ), sometimes called the black-handed spider monkey; 5. Chamek spider monkey (A. chamek ); and 6. white-whiskered spider monkey (A. marginatus ).
General characteristics
The head and the body length of spider monkeys ranges from 13-23 in (34-59 cm). Their tails are longer, ranging between 24-36 in (61-92 cm). The sexes are about the same size, but the males can be fairly easily determined because of their noticeably longer canine teeth. The arms, hands, legs, and feet are all very long and thin, as are their bodies. Interestingly, their tails, which often act as a fifth arm or leg, are without fur for about 3.2 in (8 cm) on the underside near the tip. The absence of fur probably enhances their tails” sensitivity and ability to grasp objects.
These monkeys are almost always found in trees and inhabit a variety of forest types. Second only to the gibbon in agility, they are masters at locomotion. They move around in the trees using all four limbs, as well as their tails. Their long, prehensile tails can easily support their body weight and enable them to jump from tree to tree with ease. They are able to leap large distances into dense masses of branches, which is especially useful if they are in a situation where they need to break their fall. Sometimes, when watching for danger, these monkeys stand on two feet; in doing this, their tails usually provide support.
For most species of spider monkey, the fur on the coat is coarse, although some species have finer, softer fur. A spider monkey’s fur has a variety of basic colors, including yellowish gray, darker gray, reddish brown, darker brown, and almost black. While some underfur is lacking in all species of spider monkey, the monkeys” underparts are typically a lighter shade than their backs. These monkeys” bodies lack sharp contrasts in color, although sometimes darker monkeys will have lighter fur on their faces, especially near their eyes. Their skin tone varies, but usually, when exposed, it appears black. It can be lighter around their eyes, and a few varieties of spider monkeys have light skin on their faces.
The appearance of the spider monkey species
Of the six species, the black spider monkey and the brown-headed spider monkey are basically entirely black, although, as its name indicates, the brown-headed spider monkey often has a brown crown on its head. The white-bellied spider monkey, which lives in Colombia, is usually very dark brown or nearly black and has a pale underside and forehead. It gets its name from its pale underside. The black spider monkey can appear gold, tan, or dark brown. It usually has occasional black markings.
Whatever their particular coloring will be at adulthood, young spider monkeys are always black for the first six months of their lives. At this time, their colors take on whatever their adult appearance will be, and themonkeys are weaned.
Social behavior
Spider monkeys are extremely social animals. In fact, if one is kept alone in captivity, it can easily die of loneliness unless its owner gives it a great deal of attention. In the wild, these monkeys tend to congregate in groups of 40 –50, although they break up into smaller groups during the course of the day. Each large group has its own territory, and members of the group patrol it daily on specific paths. Spider monkeys rarely enter neighboring territories. Whenever spider monkey territories overlap, the monkeys somehow readjust them over time.
The smaller group of spider monkeys can be composed of various troop members, depending on the specifics of the day. Small groups can be composed of a single male with his offspring and mates, a female and her young, or several females and their young, or even several males temporarily associating with each other. When in the forest, the small groups tend to stay within calling distance of each other. When danger is at hand, the large group can be reassembled quickly through a series of bark-like calls by various members of the small groups.
One American zoologist studying the black spider monkey in Panama obviously presented a threat to them; thus, he was attacked several times by the monkeys he studied. He reported that, at these times, the monkeys emitted rough barks and migrated to lower tree limbs. Their barking calls came closer and closer together, until they sounded almost like a unified metallic clanging noise. Some of the stronger males and females then shook the lower tree branches and growled at him. However, the monkeys never approached the zoologist closer than 39 ft (12 m). At this distance, the monkeys broke limbs from the trees with their hands, feet, and tails and dropped them on him.
Spider monkeys have barks that are much worse than their bites. Their seemingly crazy behavior is designed solely to frighten the intruder and is merely a bluff. Thus, when their threats are not heeded, they tend to split into smaller subgroups and move away from the danger in different directions. Moreover, spider monkeys only threaten human beings if they have not encountered them previously. Once they have a negative experience with human beings, they are cautious and try to elude them without notice.
Grooming occurs during certain times of the day when monkeys pick the parasites off of other monkeys in their troop. While grooming is a highly social behavior, spider monkeys do not commonly do this. Since they do not have thumbs, they are not very skilled at grooming themselves. Thus, they scratch themselves a lot with both their hands and feet. On the infrequent occasions when spider monkeys do groom each other, it usually takes place with mothers grooming their young.
Diet
These trapeze artists of the jungle prefer to eat a higher proportion of fruit in their diets than do other New World monkeys. In fact, the zoologist in Panama mentioned above reported that the monkeys he studied ate a diet consisting of about 90% fruits and nuts. They also eat leaves and young stems. However, spider monkeys are not entirely vegetarian. They have been seen reaching under tree bark and into rotten logs; in all probability, they do this to find bugs and larvae to eat. Some zoologists believe that they also eat small birds and even small mammals.
Captive spider monkeys
When in captivity, their high-fruit diet makes spider monkeys fairly easy to feed. In fact, they are convenient for many zoos to keep because they eat basically the same diet as capuchin monkeys. However, they require some special care if they are to thrive in captivity. They must be kept in groups to allow them to interact socially. If possible, one male should be kept in a group with several females, although it can be hard to differentiate between the sexes. Furthermore, the temperature in their environment should not drop below 75°F (23.8°C) because they do not adapt well to climate changes. Also, these monkeys need a lot of room to climb.
Spider monkeys do not often give birth in captivity. Normally, their pregnancies last 139 days, and only one baby is born. The life expectancy for spider monkeys in zoos is about 4 –6 years; however, in a New York zoo, one black spider monkey lived for 20 years.
Resources
BOOKS
Hill, W.C. Osman. Evolutionary Biology of the Primates.New York: Academic Press, 1972.
Jolly, Alison. The Evolution of Primate Behavior. New York:The Macmillan Company, 1972.
Kinzey, W.G., ed. New World Primates: Ecology, Evolution and Behavior. New York: Aldine de Gruyter, 1997.
New Larousse Encyclopedia of Animal Life. New York:Bonanza Books, 1987.
Nowak, Ronald M. Walker’s Mammals of the World. 6th ed. Baltimore: The Johns Hopkins University Press, 1999.
Preston-Mafham, Rod and Ken Preston-Mafham. Primates of the World. London : Blandford Publishing, 1992.Kathryn Snavely
Kathryn Snavely
Spider Monkeys
Spider monkeys
Spider monkeys are slender, medium-sized monkeys with long limbs and very long tails. They live in trees, rarely coming down to the jungle floor. They are very adept at moving around in trees with the help of their prehensile tails; "prehensile" is a term that means their tails are well adapted for holding on to objects. These monkeys inhabit a territory ranging from southern Mexico to northern Argentina.
These New World monkeys are classified in the family known as Cebidae monkeys or "typical South American monkey." Within the Cebidae family, there are five subfamilies, consisting of 10 genera and 34 species . Spider monkeys are in the subfamily called Atelinae and the genus Ateles, meaning "imperfect" because these monkeys have very small or absent thumbs. There are four species of spider monkeys: 1. Central American spider monkey (Ateles geoffroyi); 2. Brown-headed spider monkey (Ateles fusciceps); 3. Long-haired spider monkey (Ateles belzebuth); 4. Black spider monkey (Ateles paniscus), sometimes called the Black-handed spider monkey.
General characteristics
The head and the body length of spider monkeys ranges from 13-23 in (34-59 cm). Their tails are longer, ranging between 24-36 in (61-92 cm). The sexes are about the same size, but the males can be fairly easily determined because of their noticeably longer canine teeth. The arms, hands, legs, and feet are all very long and thin, as are their bodies. Interestingly, their tails, which often act as a fifth arm or leg, are without fur for about 3.2 in (8 cm) on the underside near the tip. The absence of fur probably enhances their tails' ability to grasp objects.
These monkeys are almost always found in trees and inhabit a variety of forest types. Second only to the gibbon in agility, they are masters at locomotion. They move around in the trees using all four limbs, as well as their tails. Their long, prehensile tails can easily support their body weight and enable them to jump from tree to tree with ease. They are able to leap large distances into dense masses of branches, which is especially useful if they are in a situation where they need to break their fall. Sometimes, when watching for danger, these monkeys stand on two feet; in doing this, their tails usually provide support.
For most species of spider monkey, the fur on the coat is coarse, although some species have finer, softer fur. A spider monkey's fur has a variety of basic colors, including yellowish-gray, darker gray, reddish-brown, darker brown, and almost black. While some underfur is lacking in all species of spider monkey, the monkeys' underparts are typically a lighter shade than their backs. These monkeys' bodies lack sharp contrasts in color , although sometimes darker monkeys will have lighter fur on their faces, especially near their eyes. Their skin tone varies, but usually, when exposed, it appears black. It can be lighter around their eyes, and a few varieties of spider monkeys have almost Caucasian skin on their faces.
The appearance of the four species
Of the four species, the black spider monkey and the brown-headed spider monkey are basically entirely black, although, as its name indicates, the brown-headed spider monkey often has a brown crown on its head. The long-haired spider monkey, which lives in Colombia, is usually very dark brown or nearly black and has a pale underside and forehead. It gets its name from its long hair which falls like a cloak around its flanks. The black spider monkey can appear gold, tan, or dark brown. It usually has occasional black markings.
Whatever their particular coloring will be at adulthood, young spider monkeys are always black for the first six months of their lives. At this time, their colors take on whatever their adult appearance will be, and the monkeys are weaned.
Social behavior
Spider monkeys are extremely social animals. In fact, if one is kept alone in captivity, it can easily die of loneliness unless its owner gives it a great deal of attention. In the wild, these monkeys tend to congregate in groups of 40–50, although they break up into smaller groups during the course of the day. Each large group has its own territory, and members of the group patrol it daily on specific paths. Spider monkeys rarely enter neighboring territories. Whenever spider monkey territories over-lap, the monkeys somehow readjust them over time.
The smaller group of spider monkeys can be composed of various troupe members, depending on the specifics of the day. Small groups can be composed of a single male with his offspring and mates, a female and her young, or several females and their young, or even several males temporarily associating with each other. When in the forest, the small groups tend to stay within calling distance of each other. When danger is at hand, the large group can be reassembled quickly through a series of bark-like calls by various members of the small groups.
One American zoologist studying the black spider monkey in Panama obviously presented a threat to them; thus, he was attacked several times by the monkeys he studied. He reported that, at these times, the monkeys emitted rough barks and migrated to lower tree limbs. Their barking calls came closer and closer together, until they sounded almost like a unified metallic clanging noise. Some of the stronger males and females then shook the lower tree branches and growled at him. However, the monkeys never approached the zoologist closer than 39 ft (12 m). At this distance, the monkeys broke limbs from the trees with their hands, feet, and tails and dropped them on him.
Spider monkeys have barks that are much worse than their bites. Their seemingly crazy behavior is designed solely to frighten the intruder and is merely a bluff. Thus, when their threats are not heeded, they tend to split into smaller subgroups and move away from the danger in different directions. Moreover, spider monkeys only threaten human beings if they have not encountered them previously. Once they have a negative experience with human beings, they are cautious and try to elude them without notice.
Grooming occurs during certain times of the day when monkeys pick the parasites off of other monkeys in their troupe. While grooming is a highly social behavior, spider monkeys do not commonly do this. Since they do not have thumbs, they are not very skilled at grooming themselves. Thus, they scratch themselves a lot with both their hands and feet. On the infrequent occasions when spider monkeys do groom each other, it usually takes place with mothers grooming their young.
Diet
These trapeze artists of the jungle prefer to eat a higher proportion of fruit in their diets than do other New World monkeys. In fact, the zoologist in Panama mentioned above reported that the monkeys he studied ate a diet consisting of about 90% fruits and nuts. They also eat leaves and young stems. However, spider monkeys are not entirely vegetarian. They have been seen reaching under tree bark and into rotten logs; in all probability, they do this to find bugs and larvae to eat. Some zoologists believe that they also eat small birds and even small mammals .
In captivity
When in captivity, their high-fruit diet makes spider monkeys fairly easy to feed. In fact, they are convenient for many zoos to keep because they eat basically the same diet as capuchin monkeys. However, they require some special care if they are to thrive in captivity. They must be kept in groups to allow them to interact socially. If possible, one male should be kept in a group with several females, although it can be hard to differentiate between the sexes. Furthermore, the temperature in their environment should not drop below 75°F (23.8°C) because they do not adapt well to climate changes. Also, these monkeys need a lot of room to climb.
Spider monkeys do not often give birth in captivity. Normally, their pregnancies last 139 days, and only one baby is born. The life expectancy for spider monkeys in zoos is about 4–6 years; however, in a New York zoo, one black spider monkey lived for 20 years.
Resources
books
Hill, W.C. Osman. Evolutionary Biology of the Primates. New York: Academic Press, 1972.
Jolly, Alison. The Evolution of Primate Behavior. New York: The Macmillan Company, 1972.
The New Larousse Encyclopedia of Animal Life. New York: Bonanza Books, 1987.
Preston-Mafham, Rod and Ken. Primates of the World. London: Blandford Publishing, 1992.
Kathryn Snavely