A magnificent Ape
Saturday 7 August 2010
Saturday 25 July 2009
The Great Apes of Africa
A monkey is a nonhuman primate mammal with the exception usually of the lemurs and tarsiers. More specifically, the term monkey refers to a subset of monkeys: any of the smaller longer-tailed catarrhine or platyrrhine primates as contrasted with the apes.
Monkeys are broadly sudivided into the New World monkeys and Old World monkeys, two of the three groupings of simian primates (the third group being the apes). There are 264 known extant species of monkey.
The New World monkeys are classified within the parvorder Platyrrhini, whereas the Old World monkeys (superfamily Cercopithecoidea) form part of the parvorder Catarrhini , which also includes the apes. Thus, scientifically speaking, monkeys are paraphyletic (not a single coherent group), and Old World monkeys are actually more closely related to the apes than they are to the New World monkeys.
Due to its size (up to 1 m/3 ft) the Mandrill is often thought to be an ape, but it is actually an Old World monkey. Also, a few monkey species have the word "ape" in their common name.
Monkeys range in size from the Pygmy Marmoset, at 140 to 160 millimetres (5-6 in) long (plus tail) and 120 to 140 grams (4-5 oz) in weight, to the male Mandrill, almost 1 metre (3.3 ft) long and weighing 35 kilograms (77 lb). Some are arboreal (living in trees) while others live on the savannah; diets differ among the various species but may contain any of the following: fruit, leaves, seeds, nuts, flowers, eggs and small animals (including insects and spiders).
Some characteristics are shared among the groups; most New World monkeys have prehensile tails while Old World monkeys have non-prehensile tails or no visible tail at all. Some have trichromatic colour vision like that of humans, others are dichromats or monochromats. Although both the New and Old World monkeys, like the apes, have forward facing eyes, the faces of Old World and New World monkeys look very different, though again, each group shares some features such as the types of noses, cheeks and rumps.
According to the Oxford English Dictionary, the word "monkey" may originate in a German version of the reynard the Fox fable, published circa 1580. In this version of the fable, a character named Moneke is the son of Martin the Ape. The word Moneke may have been derived from the Italian monna, which means "a female ape". The name Moneke likely persisted over time due to the popularity of Reynard the Fox.
A group of monkeys may be referred to as a mission or a tribe. The following list shows where the various monkey families (bolded) are placed in the Primate classification. Note that the smallest grouping that contains them all is the Simiformes, the simians, which also contains the apes. Calling apes "monkeys" is incorrect. Calling either a simian is correct.
· ORDER Primates. · Suborder Strepsirrhini: non-tarsier prosimians
1 Suborder Haplorrhini: tarsiers, monkeys and apes
· Infraorder Tarsiiformes · Family Tarsiidae: tarsiers · Infraorder Simiformes: simians · Parvorder Platyrrhini: New World monkeys · Family Cebidae: marmosets, tamarins, capuchins and squirrel monkeys (56 species)
1 Family Aotidae: night monkeys, owl monkeys, douroucoulis (8 species) 2 Family Pitheciidae: titis, sakis and uakaris (41 species) 3 Family Atelidae: howler, spider and woolly monkeys (24 species)
· Parvorder Catarrhini · Superfamily Cercopithecoidea · Family Cercopithecidae: Old World monkeys (135 species) · Superfamily Hominoidea: apes · Family Hylobatidae: gibbons ("lesser apes") (13 species)
1 Family Hominidae: great apes including humans (7 species)
The many species of monkey have varied relationships with humans. Some are kept as pets, others used as model organisms in laboratories or in space missions. They may be killed in monkey drives when they threatened agriculture, or serve as service animals for the disabled.
In religion and culture, the monkey often represents quick-wittedness and mischief. Some organizations train capuchin monkeys as monkey helpers to assist quadriplegics and other people with severe spinal cord injuries or mobility impairments. After being socialized in a human home as infants, the monkeys undergo extensive training before being placed with a quadriplegic. Around the house, the monkeys help out by doing tasks including microwaving food, washing the quadriplegic's face, and opening drink bottles.
Macaques especially the Rhesus Macaque, and African green monkeys are widely used in animal testing facilities, either wild-caught or purpose-bred. They are used primarily because of their relative ease of handling, their fast reproductive cycle (compared to apes), and their psychological and physical similarity to humans. In the United States, around 50,000 non-human primates, most of them monkeys, have been used in experiments every year since 1973; 10,000 monkeys were used in the European Union in 2004.
The use of monkeys in laboratories is controversial. Some claim that their use is cruel and produces little information of value, and there have been many protests, vandalism to testing facilities, and threats to workers. Others claim that it has led to many important medical breakthroughs such as the rabies vaccine, understanding of human reproduction and basic knowledge about brain function, and that the prevention of harm to humans should be a higher priority than the possible harm done to monkeys. The topic has become a popular cause for animal rights and animal welfare groups
A number of countries have used monkeys as part of their space exploration programmes, including the United States and France. The first monkey in space was Albert II who flew in the US-launched V2 rocket in June 14, 1949.
Monkey brains are eaten as a delicacy in South Asia, China and Africa. In traditional Islamic dietry laws, monkeys are forbidden to be eaten. However, monkeys are sometimes eaten in parts of Africa, where they can be sold as "bushmeat".
Sun Wukong ,(the "Monkey King"), a character who figures prominently in Chinese mythology, is the main protagonist in the classic comic Chinese novel Journey to the West.
Monkeys are prevalent in numerous books, television programs, and movies. The television series Monkey, the literary characters Monsieur Eek and Curious george are all examples.
However, pop culture often incorrectly labels apes, particularly chimpanzees, gibbons, and gorillas, as monkeys. Terry Pratchett makes use of the distinction in his Discworld novels, in which the Librarian of the Unseen University is an orangutan who gets very violent if referred to as a monkey.
The orangutans are a species of great apes. Known for their intelligence, they live in trees and they are the largest living arboreal animal. They have longer arms than other great apes, and their hair is reddish-brown, instead of the brown or black hair typical of other great apes. Native to Indonesia and Malaysia, they are currently found only in rainforests on the islands of Borneo and Sumatra, though fossils have been found in Java, the Thai-Malay Peninsula, Vietnam and China. They are the only surviving species in the genus Pongo and the subfamily Ponginae (which also includes the extinct genera Gigantopithecus and Sivapithecus).
The word orangutan (also written orang-utan, orang utan and orangutang) is derived from the Malay and Indonesian words orang meaning "person" and hutan meaning "forest", thus "person of the forest". Orang Hutan is the common term in these two national languages, although local peoples may also refer to them by local languages. Maias and mawas are also used in Malay, but it is unclear if those words refer only to orangutans, or to all apes in general.
The word was first attested in English in 1691 in the form orang-outang, and variants with -ng instead of -n as in the Malay original are found in many languages. This spelling (and pronunciation) has remained in use in English up to the present, but has come to be regarded as incorrect.
The name of the genus, Pongo, comes from a 16th century account by Andrew Battell, an English sailor held prisoner by the Portuguese in Angola, which describes two anthropoid "monsters" named Pongo and Engeco. It is now believed that he was describing gorillas, but in the late 18th century it was believed that all great apes were orangutans; hence Lacépède's use of Pongo for the genus
Orangutans are the most arboreal of the great apes, spending nearly all of their time in the trees. Every night they fashion nests, in which they sleep, from branches and foliage. They are more solitary than the other apes, with males and females generally coming together only to mate. Mothers stay with their babies until the offspring reach an age of six or seven years. There is significant s exual dimorphism between females and males: females can grow to around 4 ft 2 in or 127 centimetres and weigh around 100 lbs or 45 kg, while flanged adult males can reach 5 ft 9 in or 175 centimetres in height and weigh over 260 lbs or 118 kg.
The arms of orangutans are twice as long as their legs. Much of the arm's length has to do with the length of the radius and the ulna rather than the humerus. Their fingers and toes are curved, allowing them to better grip onto branches. Orangutans have less restriction in the movements of their legs than humans and other primates, due to the lack of a hip joint ligament which keeps the femur held into the pelvis. Unlike gorillas and chimpanzees, orangutans are not true knuckle-walkers, and walk on the ground by shuffling on their palms with their fingers curved inwards.
Fruit makes up 65% of the orangutan diet. Fruits with sugary or fatty pulp are favored. Lowland Dipterocarp forests are preferred by orangutans because of their high fruit abundance, the same forests that provide excellent timber for the logging industry and good soil conditions for palm oil plantations. The fruit of fig trees are also commonly eaten since it is easy to both harvest and digest. Bornean orangutans are recorded to consume at least 317 different food items and include: young leaves, shoots, seeds and bark. Insects, honey and bird eggs are also included.
Orangutans are highly opportunistic foragers with the composition of their diet varying markedly from month to month. Bark as a source of nourishment is only consumed as a last resort in times of food scarcity, fruits always being the preferred choice.
Orangutans are thought to be the sole fruit disperser for some plant species including the climber species Strychnos ignatii which contains the toxic alkaloid strychnine. It does not appear to have any effect on orangutans except for excessive saliva production.
Geophagy, the practice of eating soil or rock, has been observed in orangutans. There are three main reasons for this dietary behavior; for the addition of minerals nutrients to their diet; for the ingestion of clay minerals that can absorb toxic substances; or to treat a disorder such as diarrhea.
Orangutans use plants of the genus Commelina as an anti-inflammatory balm. Like the other great apes, orangutans are remarkably intelligent. Although tool use among chimpanzees was documented by Jane Goodall in the 1960s, it was not until the mid-1990s that one population of orangutans was found to use feeding tools regularly. A 2003 paper in the journal Science described the evidence for distinct orangutan cultures.
According to recent research by the psychologist Robert Deaner and his colleagues, orangutans are the world's most intelligent animal other than humans, with higher learning and problem solving ability than chimpanzees, which were previously considered to have greater abilities. A study of orangutans by Carel van Schaik, a Dutch primatologist at Duke University, found them capable of tasks well beyond chimpanzees’ abilities — such as using leaves to make rain hats and leakproof roofs over their sleeping nests. He also found that, in some food-rich areas, the creatures had developed a complex culture in which adults would teach youngsters how to make tools and find food.
A two year study of orangutan symbolic capability was conducted from 1973-1975 by Gary L. Shapiro with Aazk, a juvenile female orangutan at the Fresno City Zoo (now Chaffee Zoo) in Fresno, California. The study employed the techniques of David Premack who used plastic tokens to teach the chimpanzee, Sarah, linguistic skills. Shapiro continued to examine the linguistic and learning abilities of ex-captive orangutans in Tanjung Putting National Park, in Indonesian Borneo, between 1978 and 1980. During that time, Shapiro instructed ex-captive orangutans in the acquisition and use of signs following the techniques of R. Allen and Beatrix Gardner who taught the chimpanzee,Washoe , in the late-1960s. In the only signing study ever conducted in a great ape's natural environment, Shapiro home-reared Princess, a juvenile female who learned nearly 40 signs (according to the criteria of sign acquisition used by Francine Patterson with Koko, the gorilla) and trained Rinnie, a free-ranging adult female orangutan who learned nearly 30 signs over a two year period. For his dissertation study, Shapiro examined the factors influencing sign learning by four juvenile orangutans over a 15-month period.
The first orangutan language study program, directed by Dr.Francine Neago, was listed by Encyclopedia Britannica in 1988. The Orangutan language project at the Smithsonian National Zoo in Washington D.C, uses a computer system originally developed at UCLA by Neago in conjunction with IBM. .
Zoo Atlanta has a touch screen computer where their two Sumatran Orangutans play games. Scientists hope that the data they collect from this will help researchers learn about socializing patterns, such as whether they mimic others or learn behavior from trial and error, and hope the data can point to new conservation strategies.
A 2008 study of two orangutans at the Leipzig Zoo showed that orangutans are the first non-human species documented to use 'calculated reciprocity' which involves weighing the costs and benefits of gift exchanges and keeping track of these over time.
Although orangutans are generally passive, aggression toward other orangutans is very common; they are solitary animals and can be fiercely territorial. Immature males will try to mate with any female, and may succeed in forcibly copulating with her if she is also immature and not strong enough to fend him off. Mature females easily fend off their immature suitors, preferring to mate with a mature male.
Orangutans usually do not swim, however they can be taught to swim and at least one population at a conservation refuge on Kaja island in Borneo have taught themselves to swim.
Orangutans have even shown laughter-like vocalizations in response to physical contact, such as wrestling, play chasing, or tickling.
The populations on the two islands were classified as subspecies until recently, when they were elevated to full specific level, and the three distinct populations on Borneo were elevated to subspecies. The population currently listed as P. p. wurmbii may be closer to the Sumatran Orangutan than the Bornean Orangutan. If confirmed, abelii would be a subspecies of P. wurmbii (Tiedeman, 1808). Regardless, the type locality of pygmaeus has not been established beyond doubts, and may be from the population currently listed as wurmbii (in which case wurmbii would be a junior synonym of pygmaeus, while one of the names currently considered a junior synonym of pygmaeus would take precedence for the northwest Bornean taxon). To further confuse, the name morio, as well as various junior synonyms that have been suggested, have been considered likely to all be junior synonyms of the population listed as pygmaeus in the above, thus leaving the east Bornean populations unnamed.
In addition, a fossil species, P.Hooijeri, is known from Vietnam, and multiple fossil subspecies have been described from several parts of southeastern Asia. It is unclear if these belong to P. pygmaeus or P. abeli or, in fact, represent distinct species.
The Sumatran species is critically endangered and the Bornean species of orangutans is endangered according to the IUCN Red List of mammals, and both are listed on Appendix I of CITES. The total number of Bornean orangutans is estimated to be less than 14% of what it was in the recent past (from around 10,000 years ago until the middle of the twentieth century) and this sharp decline has occurred mostly over the past few decades due to human activities and development. Species distribution is now highly patchy throughout Borneo: it is apparently absent or uncommon in the south-east of the island, as well as in the forests between the Rejang River in central Sarawak and the Padas River in western Sabah (including the Sultanate of Brunei). The largest remaining population is found in the forest around the Sabangau River, but this environment is at risk. A similar development have been observed for the Sumatran orangutans.
The most recent estimate for the Sumatran Orangutan is around 7,300 individuals in the wild while the Bornean Orangutan population is estimated at between 45,000 and 69,000. These estimates were obtained between 2000 and 2003. Since recent trends are steeply down in most places due to logging and burning, it is forecast that the current numbers are below these figures.
Orangutan habitat destruction due to logging, mining and forest fires, as well as fragmentation by roads, has been increasing rapidly in the last decade. A major factor in that period of time has been the conversion of vast areas of tropical forest to oil palm plantations in response to international demand (the palm oil is used for cooking, cosmetics, mechanics, and more recently as source of biodiesel). Some UN scientists believe that these plantations could lead to the extinction of the species by the year 2012. Some of this activity is illegal, occurring in national parks that are officially off limits to loggers, miners and plantation development. There is also a major problem with hunting and illegal pet trade. In early 2004 about 100 individuals of Bornean origin were confiscated in Thailand and 50 of them were returned to Kalimantan in 2006. Several hundred Bornean orangutan orphans who were confiscated by local authorities have been entrusted to different orphanages in both Malaysia and Indonesia. They are in the process of being rehabilitated into the wild.
Major conservation centres in Indonesia include those at Tanjung Putting National Park and Sebangau National Park in Central Kalimantan, Kutai in East Kalimantan, Gunung Palung National Park in West Kalimantan, and Bukit Lawang in the Gunung Leuser National Park on the border of Aceh and North Sumatra. In Malaysia, conservation areas include Semenggoh Wildlife Centre in Sarawak and Matang Wildlife Centre also in Sarawak, and the Sepilok Orang Utan sanctuary near Sandakan in Sabah.
Gorillas are the largest of the living primates. They are ground-dwelling herbivores that inhabit the forests of Africa. Gorillas are divided into two species and (still under debate as of 2008) either four or five subspecies. The DNA of gorillas is 98%-99% identical to that of a human, and they are the next closest living relatives to humans after the two chimpanzee species.
Gorillas live in tropical or subtropical forests. Although their range covers a small percentage of Africa, gorillas cover a wide range of elevations. The Mountain Gorilla inhabits the Albertine Rift montane cloud forests of the Virunga Volcanoes, ranging in altitude from 2225 to 4267 m (7300-14000 ft). Lowland Gorillas live in dense forests and lowland swamps and marshes as low as sea level.
The closest relatives of gorillas are chimpanzees and humans, from which gorillas diverged about 7 million years ago. Human genes differ only 1.6% on average from their corresponding gorilla genes in their sequence, but there is further difference in how many copies each gene has.
Until recently there was considered to be a single gorilla species, with three subspecies: the Western Lowland Gorilla, the Eastern Lowland Gorilla and the Mountain Gorilla. There is now agreement that there are two species with two subspecies each. More recently it has been claimed that a third subspecies exists in one of the species.
Primatologists continue to explore the relationships between various gorilla populations. The species and subspecies listed here are the ones upon which most scientists agree.
· Genus Gorilla · Western Gorilla (Gorilla gorilla) · Western lowland Gorilla (Gorilla gorilla gorilla) 1 Cross River Gorilla (Gorilla gorilla diehli) · Eastern Gorilla (Gorilla beringei) · Mountain Gorilla (Gorilla beringei beringei) 1 Eastern Lowland Gorilla (Gorilla beringei graueri) The proposed third subspecies of Gorilla beringei, which has not yet received a trinomen, is the Bwindi population of the Mountain Gorilla, sometimes called the Bwindi Gorilla.
A silverback is an adult male gorilla, typically more than 12 years of age and named for the distinctive patch of silver hair on his back. A silverback gorilla has large canine teeth that come with maturity. Black backs are sexually mature males of up to 11 years of age.
Silverbacks are the strong, dominant troop leaders. Each typically leads a troop (group size ranges from 5 to 30) and is in the center of the troop's attention, making all the decisions, mediating conflicts, determining the movements of the group, leading the others to feeding sites and taking responsibility for the safety and well-being of the troop. Younger males called blackbacks may serve as backup protection.
Males will slowly begin to leave their original troop when they are about 11 years old, traveling alone or with a group of other males for 2–5 years before being able to attract females to form a new group and start breeding. While infant gorillas normally stay with their mother for 3–4 years, silverbacks will care for weaned young orphans, though never to the extent of carrying the little gorillas. If challenged by a younger or even by an outsider male, a silverback will scream, beat his chest, break branches, bare his teeth, then charge forward. Sometimes a younger male in the group can take over leadership from an old male. If the leader is killed by disease, accident, fighting or poachers, the group will split up, as the animals disperse to look for a new protective male. Very occasionally, a group might be taken over in its entirety by another male. There is a strong risk that the new male may kill the infants of the dead silverback.
Gorillas are herbivores, eating fruits, leaves, and shoots. Further they are classified as foliovores. Much like other animals that feed on plants and shoots, they sometimes ingest small insects also. Gorilla spend most of the day eating. Their large sagittal crest and long canines allow them to crush hard plants like bamboo. Lowland gorillas feed mainly on fruit while Mountain gorillas feed mostly on herbs, stems and roots
Gestation is 8½ months. There are typically 3 to 4 years between births. Infants stay with their mothers for 3–4 years. Females mature at 10–12 years (earlier in captivity); males at 11–13 years. Lifespan is between 30–50 years, although there have been exceptions. For example the Dallas Zoo's Jenny lived to the age of 55. Recently, gorillas have been observed engaging in face-to-face sex, a trait that was once considered unique to humans and the Bonobo.
Gorillas move around by knuckle-walking. Adult males range in height from 165-175 cm (5 ft 5 in – 5 ft 9 in), and in weight from 140–204.5 kg (310–450 lb). Adult females are often half the size of a silverback, averaging about 140 cm (4 ft 7 in) tall and 100 kg (220 lb). Occasionally, a silverback of over 183 cm (6 ft) and 225 kg (500 lb) has been recorded in the wild. However, obese gorillas in captivity have reached a weight of 270 kg (600 lb). Gorillas have a facial structure which is described as mandibular prognathism, that is, their mandible protrudes farther out than the maxilla.
The Eastern Gorilla is more darkly colored than the Western Gorilla, with the Mountain Gorilla being the darkest of all. The Mountain Gorilla also has the thickest hair. The Western Lowland Gorilla can be brown or grayish with a reddish forehead. In addition, gorillas that live in lowland forests are more slender and agile than the more bulky Mountain Gorilla.
Almost all gorillas share the same blood type (B) and, like humans, have individual finger prints. Gorillas are closely related to humans and are considered highly intelligent. A few individuals in captivity, such as koko, have been taught a subset of sign language.
The following observations were made by a team led by Thomas Breuer of the Wildlife Conservation Society in September 2005. Gorillas are now known to use tools in the wild. A female gorilla in the Nouabale-Ndoki National Park in the Republic of Congo was recorded using a stick as if to gauge the depth of water whilst crossing a swamp. A second female was seen using a tree stump as a bridge and also as a support whilst fishing in the swamp. This means that all of the great apes are now known to use tools.
In September 2005, a two and a half year old gorilla in the Republic of Congo was discovered using rocks to smash open palm nuts inside a game sanctuary. While this was the first such observation for a gorilla, over forty years previously chimpanzees had been seen using tools in the wild, famously 'fishing' for termites. It is a common tale among native peoples that gorillas have used rocks and sticks to thwart predators, even rebuking large mammals. Great apes are endowed with a semi-precision grip, and certainly have been able to use both simple tools and even weapons, by improvising a club from a convenient fallen branch.
The word "gorilla" comes from the history of Hanno the navigator, a Carthaginian explorer on an expedition on the west African coast. They encountered "a savage people, the greater part of whom were women, whose bodies were hairy, and whom our interpreters called Gorillae". The word was then later used as the species name, though it is unknown whether what these ancient Carthaginians encountered were truly gorillas, another species of ape or monkeys, or humans.
American physician and missionary Thomas staughton Savage obtained the first specimens (the skull and other bones) during his time in liberia in Africa. The first scientific writings about describing gorillas date back to the publication of an article in 1847 in Proceedings of the Boston Society of Natural History, where Troglodytes gorilla is described, now known as the Western Gorilla. Other species of gorilla are described in the next couple of years.
Explorer Paul du Chaillu was the first westerner to see a live gorilla during his travel through western equatorial Africa from 1856 to 1859. He brought dead specimens to England in 1861.
The first systematic study was not conducted until the 1920s, when carl Akeley of the American Museum of Natural History traveled to Africa to hunt for an animal to be shot and stuffed. On his first trip he was accompanied by his friends Mary Bradley, a famous mystery writer, and her husband. After their trip, Mary Bradley wrote On the Gorilla Trail. She later became an advocate for the conservation of gorillas and wrote several more books (mainly for children). In the late 1920s and early 1930s, Robert Yerkes and his wife Ava helped further the study of gorillas when they sent Harold Bigham to Africa. Yerkes also wrote a book in 1929 about the great apes.
After WWII, George Schaller was one of the first researchers to go into the field and study primates. In 1959, he conducted a systematic study of the Mountain Gorilla in the wild and published his work. Years later, at the behest of louis Leakey and the National Geographic, Dian Fossey conducted a much longer and more comprehensive study of the Mountain Gorilla. It was not until she published her work that many misconceptions and myths about gorillas were finally disproved, including the myth that gorillas are violent.
Both species of gorilla are endangered, and have been subject to intense poaching for a long time. Threats to gorilla survival include habitat destruction and the bushmeat trade. In 2004 a population of several hundred gorillas in the Odzala National Park, Republic of Congo was essentially wiped out by the Ebola virus. A 2006 study published in Science concluded that more than 5,000 gorillas may have died in recent outbreaks of the Ebola virus in central Africa. The researchers indicated that in conjunction with commercial hunting of these apes, the virus creates "a recipe for rapid ecological extinction". Conservation efforts include the Great ape Survival Project, a partnership between the United Nations Environment Programme and the United Nations Educational, Scientific and Cultural Organization, and also an international treaty, the Agreement on the Conservation of Gorillas and Their habitats, concluded under UNEP-administered Convention on Migratory species. The Gorilla agreement is the first legally binding instrument exclusively targeting Gorilla conservation and came into effect on 1 June 2008.
The Mountain Gorilla (Gorilla beringei beringei) is one of the two subspecies of the Eastern Gorilla. There are two groups. One is found in the Virunga volcanic mountains of Central Africa, within 4 national parks: Mgahinga, in south-west Uganda; Volcanoes, in north-west Rwanda; and Virunga and Kahuzi-Biega, in the eastern Democratic Republic of Congo (DRC). The other is found in Uganda's Bwindi Impenetrable Forest. Some say that the Bwindi Group in Uganda is a 3rd species, though no description has been finished.
The Mountain Gorilla lives in rainforests in trees, plants, vines and mosses in Central Africa, in Rwanda, Zaire and Uganda. They live in an area of forty-seven thousand square kilometres. The Mountain Gorilla is a tall animal which can grow up to one point eight metres in height and can exceed two hundred and four kilograms. Its lifespan can be longer than a normal human beings lifespan. It has large bones, broad shoulders, long arms, strong jaws, strong teeth, small ears and a black face. Its body covering is black fur. The food the Mountain Gorilla eats is a variety of plants such as herbs, vines, roots, steams, bamboo, bark, flowers, fungi and sometimes insects, snails and slugs. Mountain Gorillas take a fair while until they will mate. Females take ten years and males take twelve years until they are ready to mate. It takes eight to nine moths until the baby is born. If the baby dies, the parents will have another baby very soon after. The female will have two to four babies in her lifetime, which she will care for dearly. The female gorilla usually has her baby at night so she can prepare her nest for the baby. The baby is usually born after nine months of pregnancy. When the female gorilla is just about ready for birth, she will build a nest which will have grass and branches to hold it together. Other members of her family will stay a short distance away until she has given birth. When the baby is born, her family will watch her clean her newborn. Once the baby is born it will weigh approximately one point eight kilograms. The mother will look after and hold her baby for a few months. When it is three months old it is already to try and reach things. The new baby has a pink face, pink little hands and pink little feet. The baby will darken as they grow. The baby will drink milk out of its mother’s breast until it is three months old. At four months, it will cling to its mother’s back and eventually will grow to be an adult which will create its own group and have its own babies (eventually).
Mountain Gorillas have become endangered due to habitat loss, war and poaching. The Mountain Gorilla is highly social, and lives in relatively stable, cohesive groups held together by long-term bonds between adult males and females. Relationships among females are relatively weak. These groups are nonterritorial; the silverback generally defends his group rather than his territory. In the Virunga Mountain Gorillas, the average length of tenure for a dominant silverback is 4.7 years.
61% of groups are composed of one adult male and a number of females and 36% contain more than one adult male. The remaining gorillas are either lone males or exclusively male groups, usually made up of one mature male and a few younger males. Group sizes vary from five to thirty, with an average of ten individuals. A typical group contains: one silverback, who is the group's undisputed leader; one or two blackbacks, who act as sentries; three to four sexually mature females, who are ordinarily bonded to the dominant silverback for life; and from three to six juveniles and infants.
Most males, and about 60% of females, leave their natal group. Males leave when they are about 11 years old, and often the separation process is slow: they spend more and more time on the edge of the group until they leave altogether.
The dominant silverback generally determines the movements of the group, leading it to appropriate feeding sites throughout the year. He also mediates conflicts within the group and protects it from external threats. He is the center of attention during rest sessions, and young animals frequently stay close to him and include him in their games. If a mother dies or leaves the group, the silverback is usually the one who looks after his abandoned offspring, even allowing them to sleep in his nest. Experienced silverbacks are capable of removing poachers' snares from the hands or feet of their group members.
When the dominant silverback dies or is killed by disease, accident, or poachers, the family group may be severely disrupted. Unless he leaves behind a male descendant capable of taking over his position, the group will either split up or be taken over in its entirety by an unrelated male. When a new silverback takes control of a family group, he may kill all of the infants of the dead silverback. This practice of infanticide is an effective reproductive strategy, in that the newly acquired females are then able to conceive the new male's offspring. Infanticide has not been observed in stable groups.
Severe aggression is rare in stable groups, but when two Mountain Gorilla groups meet, the two silverbacks can sometimes engage in a fight to the death, using their canines to cause deep, gaping injuries.] The entire sequence has nine steps: (1) progressively quickening hooting, (2) symbolic feeding, (3) rising bipedally, (4) throwing vegetation, (5) chest-beating with cupped hands, (6) one leg kick, (7) sideways running, two-legged to four-legged, (8) slapping and tearing vegetation, and (9) thumping the ground with palms to end display.
The midday rest period is an important time for establishing and reinforcing relationships within the group. Mutual grooming reinforces social bonds, and helps keep hair free from dirt and parasites. It is not as common among gorillas as in other primates, although females groom their offspring regularly. Young gorillas play often and are more arboreal than the large adults. Playing helps them learn how to communicate and behave within the group. Activities include wrestling, chasing and somersaults. The silverback and his females tolerate and even participate if encouraged.
Twenty-five distinct vocalizations are recognized, many of which are used primarily for group communication within dense vegetation. Sounds classified as grunts and barks are heard most frequently while traveling, and indicate the whereabouts of individual group members. They may also be used during social interactions when discipline is required. Screams and roars signal alarm or warning, and are produced most often by silverbacks. Deep, rumbling belches suggest contentment and are heard frequently during feeding and resting periods. They are the most common form of intragroup communication.
For reasons unknown, Mountain Gorillas that have been studied appear to be naturally afraid of certain reptiles. Infants, whose natural behavior is to chase anything that moves, will go out of their way to avoid chameleons and caterpillars. Koko, the gorilla trained in sign language, is afraid of crocodiles and alligators, even though she was born in captivity and has never seen them. They are also afraid of water and will cross streams only if they can do so without getting wet (ie. crossing over fallen logs). Dian Fossey observed and noted the Mountain Gorilla's obvious dislike of rain, as well.
In October 1902, Captain Robert von Beringe (1865-1940) shot two large apes during an expedition to establish the boundaries of German East Africa. One of the apes was recovered and sent to the Zoological Museum in Berlin, where Professor Paul Matschie (1861-1926) classified the animal as a new form of gorilla and named it Gorilla beringei after the man who discovered it. In 1925 Carl Akeley, a hunter from the American Museum of Natural History who wished to study the gorillas, convinced Albert I of Belgium to establish the Albert National Park to protect the animals of the Virunga mountains.
George Schaller began his 20 month observation of the Mountain Gorillas in 1959, subsequently publishing two books: The Mountain Gorilla and The Year of the Gorilla. Little was known about the life of the Mountain Gorilla before his research, which described its social organization, life history, and ecology. Following Schaller, Dian Fossey began what would become a 13 year study in 1967. Fossey made new observations, completed the first accurate census, and established active conservation practices, such as anti-poaching patrols. Ruth Keesling succeeded Fossey who was killed in 1985 and buried at the Karisoke Research Station in Rwanda. Keesling took over the Digit Fund renaming it the Dian Fossey Gorilla Fund Europe.
Mountain Gorillas are threatened by poaching, loss of habitat, and disease.
Poaching: Mountain Gorillas are not usually hunted for bushmeat, but they are frequently maimed or killed by traps and snares intended for other animals. They have been killed for their heads, hands, and feet, which are sold to collectors. Infants are sold to zoos, researchers, and people who want them as pets. The abduction of infants generally involves the loss of at least one adult, as members of a group will fight to the death to protect their young. Poaching for meat is particularly threatening in regions of political unrest. Most of the African great apes survive in areas of chronic insecurity, where automatic weapons are readily available and where there is a breakdown of law and order. The killing of mountain gorillas at Bikenge in Virunga National Park in January 2007 was a well documented case.
Habitat loss: The forests where Mountain Gorillas live are surrounded by rapidly increasing human settlement. The humans' need for land, food, and timber encroaches on the gorillas' habitat through roads, slash-and-burn agriculture, and logging. The resulting deforestation confines the gorillas to isolated forest islands. Some groups may raid crops for food, creating further animosity and retaliation.
Disease: Humans and gorillas are genetically similar enough that gorillas are vulnerable to many of the same diseases as humans. However, gorillas have not developed the immunities to resist human diseases, and infections could severely impact the population. Habituated groups that are visited by tourists have the greatest risk.
War and civil unrest: Civil wars and weak governments in central Africa, and in particular in the Congo, put conservation efforts at risk from local militias and government corruption
Conservation requires work at many levels, from local to international, and involves protection and law enforcement as well as research and education:
"Active conservation includes frequent patrols in wildlife areas to destroy poacher equipment and weapons, firm and prompt law enforcement, census counts in regions of breeding and ranging concentration, and strong safeguards for the limited habitat the animals occupy."
"Theoretical conservation seeks to encourage growth in tourism by improving existing roads that circle the mountains, by renovating the park headquarters and tourists' lodging, and by the habituation of gorillas near the park boundaries for tourists to visit and photograph."
Community-based conservation supports African ownership, provides education on the personal as well as environmental benefits of preserving protected areas, and encourages local people to take pride in and assume some of the responsibility for the protection of their parks.
In early 2007 two mountain gorillas were found dead. They appeared to be killed execution style by gunshots to the head.
Reasearchers recently have discovered that about 800,000 years ago that the mountain gorilla had evolved from the eastern gorilla
Monkeys are broadly sudivided into the New World monkeys and Old World monkeys, two of the three groupings of simian primates (the third group being the apes). There are 264 known extant species of monkey.
The New World monkeys are classified within the parvorder Platyrrhini, whereas the Old World monkeys (superfamily Cercopithecoidea) form part of the parvorder Catarrhini , which also includes the apes. Thus, scientifically speaking, monkeys are paraphyletic (not a single coherent group), and Old World monkeys are actually more closely related to the apes than they are to the New World monkeys.
Due to its size (up to 1 m/3 ft) the Mandrill is often thought to be an ape, but it is actually an Old World monkey. Also, a few monkey species have the word "ape" in their common name.
Monkeys range in size from the Pygmy Marmoset, at 140 to 160 millimetres (5-6 in) long (plus tail) and 120 to 140 grams (4-5 oz) in weight, to the male Mandrill, almost 1 metre (3.3 ft) long and weighing 35 kilograms (77 lb). Some are arboreal (living in trees) while others live on the savannah; diets differ among the various species but may contain any of the following: fruit, leaves, seeds, nuts, flowers, eggs and small animals (including insects and spiders).
Some characteristics are shared among the groups; most New World monkeys have prehensile tails while Old World monkeys have non-prehensile tails or no visible tail at all. Some have trichromatic colour vision like that of humans, others are dichromats or monochromats. Although both the New and Old World monkeys, like the apes, have forward facing eyes, the faces of Old World and New World monkeys look very different, though again, each group shares some features such as the types of noses, cheeks and rumps.
According to the Oxford English Dictionary, the word "monkey" may originate in a German version of the reynard the Fox fable, published circa 1580. In this version of the fable, a character named Moneke is the son of Martin the Ape. The word Moneke may have been derived from the Italian monna, which means "a female ape". The name Moneke likely persisted over time due to the popularity of Reynard the Fox.
A group of monkeys may be referred to as a mission or a tribe. The following list shows where the various monkey families (bolded) are placed in the Primate classification. Note that the smallest grouping that contains them all is the Simiformes, the simians, which also contains the apes. Calling apes "monkeys" is incorrect. Calling either a simian is correct.
· ORDER Primates. · Suborder Strepsirrhini: non-tarsier prosimians
1 Suborder Haplorrhini: tarsiers, monkeys and apes
· Infraorder Tarsiiformes · Family Tarsiidae: tarsiers · Infraorder Simiformes: simians · Parvorder Platyrrhini: New World monkeys · Family Cebidae: marmosets, tamarins, capuchins and squirrel monkeys (56 species)
1 Family Aotidae: night monkeys, owl monkeys, douroucoulis (8 species) 2 Family Pitheciidae: titis, sakis and uakaris (41 species) 3 Family Atelidae: howler, spider and woolly monkeys (24 species)
· Parvorder Catarrhini · Superfamily Cercopithecoidea · Family Cercopithecidae: Old World monkeys (135 species) · Superfamily Hominoidea: apes · Family Hylobatidae: gibbons ("lesser apes") (13 species)
1 Family Hominidae: great apes including humans (7 species)
The many species of monkey have varied relationships with humans. Some are kept as pets, others used as model organisms in laboratories or in space missions. They may be killed in monkey drives when they threatened agriculture, or serve as service animals for the disabled.
In religion and culture, the monkey often represents quick-wittedness and mischief. Some organizations train capuchin monkeys as monkey helpers to assist quadriplegics and other people with severe spinal cord injuries or mobility impairments. After being socialized in a human home as infants, the monkeys undergo extensive training before being placed with a quadriplegic. Around the house, the monkeys help out by doing tasks including microwaving food, washing the quadriplegic's face, and opening drink bottles.
Macaques especially the Rhesus Macaque, and African green monkeys are widely used in animal testing facilities, either wild-caught or purpose-bred. They are used primarily because of their relative ease of handling, their fast reproductive cycle (compared to apes), and their psychological and physical similarity to humans. In the United States, around 50,000 non-human primates, most of them monkeys, have been used in experiments every year since 1973; 10,000 monkeys were used in the European Union in 2004.
The use of monkeys in laboratories is controversial. Some claim that their use is cruel and produces little information of value, and there have been many protests, vandalism to testing facilities, and threats to workers. Others claim that it has led to many important medical breakthroughs such as the rabies vaccine, understanding of human reproduction and basic knowledge about brain function, and that the prevention of harm to humans should be a higher priority than the possible harm done to monkeys. The topic has become a popular cause for animal rights and animal welfare groups
A number of countries have used monkeys as part of their space exploration programmes, including the United States and France. The first monkey in space was Albert II who flew in the US-launched V2 rocket in June 14, 1949.
Monkey brains are eaten as a delicacy in South Asia, China and Africa. In traditional Islamic dietry laws, monkeys are forbidden to be eaten. However, monkeys are sometimes eaten in parts of Africa, where they can be sold as "bushmeat".
Sun Wukong ,(the "Monkey King"), a character who figures prominently in Chinese mythology, is the main protagonist in the classic comic Chinese novel Journey to the West.
Monkeys are prevalent in numerous books, television programs, and movies. The television series Monkey, the literary characters Monsieur Eek and Curious george are all examples.
However, pop culture often incorrectly labels apes, particularly chimpanzees, gibbons, and gorillas, as monkeys. Terry Pratchett makes use of the distinction in his Discworld novels, in which the Librarian of the Unseen University is an orangutan who gets very violent if referred to as a monkey.
The orangutans are a species of great apes. Known for their intelligence, they live in trees and they are the largest living arboreal animal. They have longer arms than other great apes, and their hair is reddish-brown, instead of the brown or black hair typical of other great apes. Native to Indonesia and Malaysia, they are currently found only in rainforests on the islands of Borneo and Sumatra, though fossils have been found in Java, the Thai-Malay Peninsula, Vietnam and China. They are the only surviving species in the genus Pongo and the subfamily Ponginae (which also includes the extinct genera Gigantopithecus and Sivapithecus).
The word orangutan (also written orang-utan, orang utan and orangutang) is derived from the Malay and Indonesian words orang meaning "person" and hutan meaning "forest", thus "person of the forest". Orang Hutan is the common term in these two national languages, although local peoples may also refer to them by local languages. Maias and mawas are also used in Malay, but it is unclear if those words refer only to orangutans, or to all apes in general.
The word was first attested in English in 1691 in the form orang-outang, and variants with -ng instead of -n as in the Malay original are found in many languages. This spelling (and pronunciation) has remained in use in English up to the present, but has come to be regarded as incorrect.
The name of the genus, Pongo, comes from a 16th century account by Andrew Battell, an English sailor held prisoner by the Portuguese in Angola, which describes two anthropoid "monsters" named Pongo and Engeco. It is now believed that he was describing gorillas, but in the late 18th century it was believed that all great apes were orangutans; hence Lacépède's use of Pongo for the genus
Orangutans are the most arboreal of the great apes, spending nearly all of their time in the trees. Every night they fashion nests, in which they sleep, from branches and foliage. They are more solitary than the other apes, with males and females generally coming together only to mate. Mothers stay with their babies until the offspring reach an age of six or seven years. There is significant s exual dimorphism between females and males: females can grow to around 4 ft 2 in or 127 centimetres and weigh around 100 lbs or 45 kg, while flanged adult males can reach 5 ft 9 in or 175 centimetres in height and weigh over 260 lbs or 118 kg.
The arms of orangutans are twice as long as their legs. Much of the arm's length has to do with the length of the radius and the ulna rather than the humerus. Their fingers and toes are curved, allowing them to better grip onto branches. Orangutans have less restriction in the movements of their legs than humans and other primates, due to the lack of a hip joint ligament which keeps the femur held into the pelvis. Unlike gorillas and chimpanzees, orangutans are not true knuckle-walkers, and walk on the ground by shuffling on their palms with their fingers curved inwards.
Fruit makes up 65% of the orangutan diet. Fruits with sugary or fatty pulp are favored. Lowland Dipterocarp forests are preferred by orangutans because of their high fruit abundance, the same forests that provide excellent timber for the logging industry and good soil conditions for palm oil plantations. The fruit of fig trees are also commonly eaten since it is easy to both harvest and digest. Bornean orangutans are recorded to consume at least 317 different food items and include: young leaves, shoots, seeds and bark. Insects, honey and bird eggs are also included.
Orangutans are highly opportunistic foragers with the composition of their diet varying markedly from month to month. Bark as a source of nourishment is only consumed as a last resort in times of food scarcity, fruits always being the preferred choice.
Orangutans are thought to be the sole fruit disperser for some plant species including the climber species Strychnos ignatii which contains the toxic alkaloid strychnine. It does not appear to have any effect on orangutans except for excessive saliva production.
Geophagy, the practice of eating soil or rock, has been observed in orangutans. There are three main reasons for this dietary behavior; for the addition of minerals nutrients to their diet; for the ingestion of clay minerals that can absorb toxic substances; or to treat a disorder such as diarrhea.
Orangutans use plants of the genus Commelina as an anti-inflammatory balm. Like the other great apes, orangutans are remarkably intelligent. Although tool use among chimpanzees was documented by Jane Goodall in the 1960s, it was not until the mid-1990s that one population of orangutans was found to use feeding tools regularly. A 2003 paper in the journal Science described the evidence for distinct orangutan cultures.
According to recent research by the psychologist Robert Deaner and his colleagues, orangutans are the world's most intelligent animal other than humans, with higher learning and problem solving ability than chimpanzees, which were previously considered to have greater abilities. A study of orangutans by Carel van Schaik, a Dutch primatologist at Duke University, found them capable of tasks well beyond chimpanzees’ abilities — such as using leaves to make rain hats and leakproof roofs over their sleeping nests. He also found that, in some food-rich areas, the creatures had developed a complex culture in which adults would teach youngsters how to make tools and find food.
A two year study of orangutan symbolic capability was conducted from 1973-1975 by Gary L. Shapiro with Aazk, a juvenile female orangutan at the Fresno City Zoo (now Chaffee Zoo) in Fresno, California. The study employed the techniques of David Premack who used plastic tokens to teach the chimpanzee, Sarah, linguistic skills. Shapiro continued to examine the linguistic and learning abilities of ex-captive orangutans in Tanjung Putting National Park, in Indonesian Borneo, between 1978 and 1980. During that time, Shapiro instructed ex-captive orangutans in the acquisition and use of signs following the techniques of R. Allen and Beatrix Gardner who taught the chimpanzee,Washoe , in the late-1960s. In the only signing study ever conducted in a great ape's natural environment, Shapiro home-reared Princess, a juvenile female who learned nearly 40 signs (according to the criteria of sign acquisition used by Francine Patterson with Koko, the gorilla) and trained Rinnie, a free-ranging adult female orangutan who learned nearly 30 signs over a two year period. For his dissertation study, Shapiro examined the factors influencing sign learning by four juvenile orangutans over a 15-month period.
The first orangutan language study program, directed by Dr.Francine Neago, was listed by Encyclopedia Britannica in 1988. The Orangutan language project at the Smithsonian National Zoo in Washington D.C, uses a computer system originally developed at UCLA by Neago in conjunction with IBM. .
Zoo Atlanta has a touch screen computer where their two Sumatran Orangutans play games. Scientists hope that the data they collect from this will help researchers learn about socializing patterns, such as whether they mimic others or learn behavior from trial and error, and hope the data can point to new conservation strategies.
A 2008 study of two orangutans at the Leipzig Zoo showed that orangutans are the first non-human species documented to use 'calculated reciprocity' which involves weighing the costs and benefits of gift exchanges and keeping track of these over time.
Although orangutans are generally passive, aggression toward other orangutans is very common; they are solitary animals and can be fiercely territorial. Immature males will try to mate with any female, and may succeed in forcibly copulating with her if she is also immature and not strong enough to fend him off. Mature females easily fend off their immature suitors, preferring to mate with a mature male.
Orangutans usually do not swim, however they can be taught to swim and at least one population at a conservation refuge on Kaja island in Borneo have taught themselves to swim.
Orangutans have even shown laughter-like vocalizations in response to physical contact, such as wrestling, play chasing, or tickling.
The populations on the two islands were classified as subspecies until recently, when they were elevated to full specific level, and the three distinct populations on Borneo were elevated to subspecies. The population currently listed as P. p. wurmbii may be closer to the Sumatran Orangutan than the Bornean Orangutan. If confirmed, abelii would be a subspecies of P. wurmbii (Tiedeman, 1808). Regardless, the type locality of pygmaeus has not been established beyond doubts, and may be from the population currently listed as wurmbii (in which case wurmbii would be a junior synonym of pygmaeus, while one of the names currently considered a junior synonym of pygmaeus would take precedence for the northwest Bornean taxon). To further confuse, the name morio, as well as various junior synonyms that have been suggested, have been considered likely to all be junior synonyms of the population listed as pygmaeus in the above, thus leaving the east Bornean populations unnamed.
In addition, a fossil species, P.Hooijeri, is known from Vietnam, and multiple fossil subspecies have been described from several parts of southeastern Asia. It is unclear if these belong to P. pygmaeus or P. abeli or, in fact, represent distinct species.
The Sumatran species is critically endangered and the Bornean species of orangutans is endangered according to the IUCN Red List of mammals, and both are listed on Appendix I of CITES. The total number of Bornean orangutans is estimated to be less than 14% of what it was in the recent past (from around 10,000 years ago until the middle of the twentieth century) and this sharp decline has occurred mostly over the past few decades due to human activities and development. Species distribution is now highly patchy throughout Borneo: it is apparently absent or uncommon in the south-east of the island, as well as in the forests between the Rejang River in central Sarawak and the Padas River in western Sabah (including the Sultanate of Brunei). The largest remaining population is found in the forest around the Sabangau River, but this environment is at risk. A similar development have been observed for the Sumatran orangutans.
The most recent estimate for the Sumatran Orangutan is around 7,300 individuals in the wild while the Bornean Orangutan population is estimated at between 45,000 and 69,000. These estimates were obtained between 2000 and 2003. Since recent trends are steeply down in most places due to logging and burning, it is forecast that the current numbers are below these figures.
Orangutan habitat destruction due to logging, mining and forest fires, as well as fragmentation by roads, has been increasing rapidly in the last decade. A major factor in that period of time has been the conversion of vast areas of tropical forest to oil palm plantations in response to international demand (the palm oil is used for cooking, cosmetics, mechanics, and more recently as source of biodiesel). Some UN scientists believe that these plantations could lead to the extinction of the species by the year 2012. Some of this activity is illegal, occurring in national parks that are officially off limits to loggers, miners and plantation development. There is also a major problem with hunting and illegal pet trade. In early 2004 about 100 individuals of Bornean origin were confiscated in Thailand and 50 of them were returned to Kalimantan in 2006. Several hundred Bornean orangutan orphans who were confiscated by local authorities have been entrusted to different orphanages in both Malaysia and Indonesia. They are in the process of being rehabilitated into the wild.
Major conservation centres in Indonesia include those at Tanjung Putting National Park and Sebangau National Park in Central Kalimantan, Kutai in East Kalimantan, Gunung Palung National Park in West Kalimantan, and Bukit Lawang in the Gunung Leuser National Park on the border of Aceh and North Sumatra. In Malaysia, conservation areas include Semenggoh Wildlife Centre in Sarawak and Matang Wildlife Centre also in Sarawak, and the Sepilok Orang Utan sanctuary near Sandakan in Sabah.
Gorillas are the largest of the living primates. They are ground-dwelling herbivores that inhabit the forests of Africa. Gorillas are divided into two species and (still under debate as of 2008) either four or five subspecies. The DNA of gorillas is 98%-99% identical to that of a human, and they are the next closest living relatives to humans after the two chimpanzee species.
Gorillas live in tropical or subtropical forests. Although their range covers a small percentage of Africa, gorillas cover a wide range of elevations. The Mountain Gorilla inhabits the Albertine Rift montane cloud forests of the Virunga Volcanoes, ranging in altitude from 2225 to 4267 m (7300-14000 ft). Lowland Gorillas live in dense forests and lowland swamps and marshes as low as sea level.
The closest relatives of gorillas are chimpanzees and humans, from which gorillas diverged about 7 million years ago. Human genes differ only 1.6% on average from their corresponding gorilla genes in their sequence, but there is further difference in how many copies each gene has.
Until recently there was considered to be a single gorilla species, with three subspecies: the Western Lowland Gorilla, the Eastern Lowland Gorilla and the Mountain Gorilla. There is now agreement that there are two species with two subspecies each. More recently it has been claimed that a third subspecies exists in one of the species.
Primatologists continue to explore the relationships between various gorilla populations. The species and subspecies listed here are the ones upon which most scientists agree.
· Genus Gorilla · Western Gorilla (Gorilla gorilla) · Western lowland Gorilla (Gorilla gorilla gorilla) 1 Cross River Gorilla (Gorilla gorilla diehli) · Eastern Gorilla (Gorilla beringei) · Mountain Gorilla (Gorilla beringei beringei) 1 Eastern Lowland Gorilla (Gorilla beringei graueri) The proposed third subspecies of Gorilla beringei, which has not yet received a trinomen, is the Bwindi population of the Mountain Gorilla, sometimes called the Bwindi Gorilla.
A silverback is an adult male gorilla, typically more than 12 years of age and named for the distinctive patch of silver hair on his back. A silverback gorilla has large canine teeth that come with maturity. Black backs are sexually mature males of up to 11 years of age.
Silverbacks are the strong, dominant troop leaders. Each typically leads a troop (group size ranges from 5 to 30) and is in the center of the troop's attention, making all the decisions, mediating conflicts, determining the movements of the group, leading the others to feeding sites and taking responsibility for the safety and well-being of the troop. Younger males called blackbacks may serve as backup protection.
Males will slowly begin to leave their original troop when they are about 11 years old, traveling alone or with a group of other males for 2–5 years before being able to attract females to form a new group and start breeding. While infant gorillas normally stay with their mother for 3–4 years, silverbacks will care for weaned young orphans, though never to the extent of carrying the little gorillas. If challenged by a younger or even by an outsider male, a silverback will scream, beat his chest, break branches, bare his teeth, then charge forward. Sometimes a younger male in the group can take over leadership from an old male. If the leader is killed by disease, accident, fighting or poachers, the group will split up, as the animals disperse to look for a new protective male. Very occasionally, a group might be taken over in its entirety by another male. There is a strong risk that the new male may kill the infants of the dead silverback.
Gorillas are herbivores, eating fruits, leaves, and shoots. Further they are classified as foliovores. Much like other animals that feed on plants and shoots, they sometimes ingest small insects also. Gorilla spend most of the day eating. Their large sagittal crest and long canines allow them to crush hard plants like bamboo. Lowland gorillas feed mainly on fruit while Mountain gorillas feed mostly on herbs, stems and roots
Gestation is 8½ months. There are typically 3 to 4 years between births. Infants stay with their mothers for 3–4 years. Females mature at 10–12 years (earlier in captivity); males at 11–13 years. Lifespan is between 30–50 years, although there have been exceptions. For example the Dallas Zoo's Jenny lived to the age of 55. Recently, gorillas have been observed engaging in face-to-face sex, a trait that was once considered unique to humans and the Bonobo.
Gorillas move around by knuckle-walking. Adult males range in height from 165-175 cm (5 ft 5 in – 5 ft 9 in), and in weight from 140–204.5 kg (310–450 lb). Adult females are often half the size of a silverback, averaging about 140 cm (4 ft 7 in) tall and 100 kg (220 lb). Occasionally, a silverback of over 183 cm (6 ft) and 225 kg (500 lb) has been recorded in the wild. However, obese gorillas in captivity have reached a weight of 270 kg (600 lb). Gorillas have a facial structure which is described as mandibular prognathism, that is, their mandible protrudes farther out than the maxilla.
The Eastern Gorilla is more darkly colored than the Western Gorilla, with the Mountain Gorilla being the darkest of all. The Mountain Gorilla also has the thickest hair. The Western Lowland Gorilla can be brown or grayish with a reddish forehead. In addition, gorillas that live in lowland forests are more slender and agile than the more bulky Mountain Gorilla.
Almost all gorillas share the same blood type (B) and, like humans, have individual finger prints. Gorillas are closely related to humans and are considered highly intelligent. A few individuals in captivity, such as koko, have been taught a subset of sign language.
The following observations were made by a team led by Thomas Breuer of the Wildlife Conservation Society in September 2005. Gorillas are now known to use tools in the wild. A female gorilla in the Nouabale-Ndoki National Park in the Republic of Congo was recorded using a stick as if to gauge the depth of water whilst crossing a swamp. A second female was seen using a tree stump as a bridge and also as a support whilst fishing in the swamp. This means that all of the great apes are now known to use tools.
In September 2005, a two and a half year old gorilla in the Republic of Congo was discovered using rocks to smash open palm nuts inside a game sanctuary. While this was the first such observation for a gorilla, over forty years previously chimpanzees had been seen using tools in the wild, famously 'fishing' for termites. It is a common tale among native peoples that gorillas have used rocks and sticks to thwart predators, even rebuking large mammals. Great apes are endowed with a semi-precision grip, and certainly have been able to use both simple tools and even weapons, by improvising a club from a convenient fallen branch.
The word "gorilla" comes from the history of Hanno the navigator, a Carthaginian explorer on an expedition on the west African coast. They encountered "a savage people, the greater part of whom were women, whose bodies were hairy, and whom our interpreters called Gorillae". The word was then later used as the species name, though it is unknown whether what these ancient Carthaginians encountered were truly gorillas, another species of ape or monkeys, or humans.
American physician and missionary Thomas staughton Savage obtained the first specimens (the skull and other bones) during his time in liberia in Africa. The first scientific writings about describing gorillas date back to the publication of an article in 1847 in Proceedings of the Boston Society of Natural History, where Troglodytes gorilla is described, now known as the Western Gorilla. Other species of gorilla are described in the next couple of years.
Explorer Paul du Chaillu was the first westerner to see a live gorilla during his travel through western equatorial Africa from 1856 to 1859. He brought dead specimens to England in 1861.
The first systematic study was not conducted until the 1920s, when carl Akeley of the American Museum of Natural History traveled to Africa to hunt for an animal to be shot and stuffed. On his first trip he was accompanied by his friends Mary Bradley, a famous mystery writer, and her husband. After their trip, Mary Bradley wrote On the Gorilla Trail. She later became an advocate for the conservation of gorillas and wrote several more books (mainly for children). In the late 1920s and early 1930s, Robert Yerkes and his wife Ava helped further the study of gorillas when they sent Harold Bigham to Africa. Yerkes also wrote a book in 1929 about the great apes.
After WWII, George Schaller was one of the first researchers to go into the field and study primates. In 1959, he conducted a systematic study of the Mountain Gorilla in the wild and published his work. Years later, at the behest of louis Leakey and the National Geographic, Dian Fossey conducted a much longer and more comprehensive study of the Mountain Gorilla. It was not until she published her work that many misconceptions and myths about gorillas were finally disproved, including the myth that gorillas are violent.
Both species of gorilla are endangered, and have been subject to intense poaching for a long time. Threats to gorilla survival include habitat destruction and the bushmeat trade. In 2004 a population of several hundred gorillas in the Odzala National Park, Republic of Congo was essentially wiped out by the Ebola virus. A 2006 study published in Science concluded that more than 5,000 gorillas may have died in recent outbreaks of the Ebola virus in central Africa. The researchers indicated that in conjunction with commercial hunting of these apes, the virus creates "a recipe for rapid ecological extinction". Conservation efforts include the Great ape Survival Project, a partnership between the United Nations Environment Programme and the United Nations Educational, Scientific and Cultural Organization, and also an international treaty, the Agreement on the Conservation of Gorillas and Their habitats, concluded under UNEP-administered Convention on Migratory species. The Gorilla agreement is the first legally binding instrument exclusively targeting Gorilla conservation and came into effect on 1 June 2008.
The Mountain Gorilla (Gorilla beringei beringei) is one of the two subspecies of the Eastern Gorilla. There are two groups. One is found in the Virunga volcanic mountains of Central Africa, within 4 national parks: Mgahinga, in south-west Uganda; Volcanoes, in north-west Rwanda; and Virunga and Kahuzi-Biega, in the eastern Democratic Republic of Congo (DRC). The other is found in Uganda's Bwindi Impenetrable Forest. Some say that the Bwindi Group in Uganda is a 3rd species, though no description has been finished.
The Mountain Gorilla lives in rainforests in trees, plants, vines and mosses in Central Africa, in Rwanda, Zaire and Uganda. They live in an area of forty-seven thousand square kilometres. The Mountain Gorilla is a tall animal which can grow up to one point eight metres in height and can exceed two hundred and four kilograms. Its lifespan can be longer than a normal human beings lifespan. It has large bones, broad shoulders, long arms, strong jaws, strong teeth, small ears and a black face. Its body covering is black fur. The food the Mountain Gorilla eats is a variety of plants such as herbs, vines, roots, steams, bamboo, bark, flowers, fungi and sometimes insects, snails and slugs. Mountain Gorillas take a fair while until they will mate. Females take ten years and males take twelve years until they are ready to mate. It takes eight to nine moths until the baby is born. If the baby dies, the parents will have another baby very soon after. The female will have two to four babies in her lifetime, which she will care for dearly. The female gorilla usually has her baby at night so she can prepare her nest for the baby. The baby is usually born after nine months of pregnancy. When the female gorilla is just about ready for birth, she will build a nest which will have grass and branches to hold it together. Other members of her family will stay a short distance away until she has given birth. When the baby is born, her family will watch her clean her newborn. Once the baby is born it will weigh approximately one point eight kilograms. The mother will look after and hold her baby for a few months. When it is three months old it is already to try and reach things. The new baby has a pink face, pink little hands and pink little feet. The baby will darken as they grow. The baby will drink milk out of its mother’s breast until it is three months old. At four months, it will cling to its mother’s back and eventually will grow to be an adult which will create its own group and have its own babies (eventually).
Mountain Gorillas have become endangered due to habitat loss, war and poaching. The Mountain Gorilla is highly social, and lives in relatively stable, cohesive groups held together by long-term bonds between adult males and females. Relationships among females are relatively weak. These groups are nonterritorial; the silverback generally defends his group rather than his territory. In the Virunga Mountain Gorillas, the average length of tenure for a dominant silverback is 4.7 years.
61% of groups are composed of one adult male and a number of females and 36% contain more than one adult male. The remaining gorillas are either lone males or exclusively male groups, usually made up of one mature male and a few younger males. Group sizes vary from five to thirty, with an average of ten individuals. A typical group contains: one silverback, who is the group's undisputed leader; one or two blackbacks, who act as sentries; three to four sexually mature females, who are ordinarily bonded to the dominant silverback for life; and from three to six juveniles and infants.
Most males, and about 60% of females, leave their natal group. Males leave when they are about 11 years old, and often the separation process is slow: they spend more and more time on the edge of the group until they leave altogether.
The dominant silverback generally determines the movements of the group, leading it to appropriate feeding sites throughout the year. He also mediates conflicts within the group and protects it from external threats. He is the center of attention during rest sessions, and young animals frequently stay close to him and include him in their games. If a mother dies or leaves the group, the silverback is usually the one who looks after his abandoned offspring, even allowing them to sleep in his nest. Experienced silverbacks are capable of removing poachers' snares from the hands or feet of their group members.
When the dominant silverback dies or is killed by disease, accident, or poachers, the family group may be severely disrupted. Unless he leaves behind a male descendant capable of taking over his position, the group will either split up or be taken over in its entirety by an unrelated male. When a new silverback takes control of a family group, he may kill all of the infants of the dead silverback. This practice of infanticide is an effective reproductive strategy, in that the newly acquired females are then able to conceive the new male's offspring. Infanticide has not been observed in stable groups.
Severe aggression is rare in stable groups, but when two Mountain Gorilla groups meet, the two silverbacks can sometimes engage in a fight to the death, using their canines to cause deep, gaping injuries.] The entire sequence has nine steps: (1) progressively quickening hooting, (2) symbolic feeding, (3) rising bipedally, (4) throwing vegetation, (5) chest-beating with cupped hands, (6) one leg kick, (7) sideways running, two-legged to four-legged, (8) slapping and tearing vegetation, and (9) thumping the ground with palms to end display.
The midday rest period is an important time for establishing and reinforcing relationships within the group. Mutual grooming reinforces social bonds, and helps keep hair free from dirt and parasites. It is not as common among gorillas as in other primates, although females groom their offspring regularly. Young gorillas play often and are more arboreal than the large adults. Playing helps them learn how to communicate and behave within the group. Activities include wrestling, chasing and somersaults. The silverback and his females tolerate and even participate if encouraged.
Twenty-five distinct vocalizations are recognized, many of which are used primarily for group communication within dense vegetation. Sounds classified as grunts and barks are heard most frequently while traveling, and indicate the whereabouts of individual group members. They may also be used during social interactions when discipline is required. Screams and roars signal alarm or warning, and are produced most often by silverbacks. Deep, rumbling belches suggest contentment and are heard frequently during feeding and resting periods. They are the most common form of intragroup communication.
For reasons unknown, Mountain Gorillas that have been studied appear to be naturally afraid of certain reptiles. Infants, whose natural behavior is to chase anything that moves, will go out of their way to avoid chameleons and caterpillars. Koko, the gorilla trained in sign language, is afraid of crocodiles and alligators, even though she was born in captivity and has never seen them. They are also afraid of water and will cross streams only if they can do so without getting wet (ie. crossing over fallen logs). Dian Fossey observed and noted the Mountain Gorilla's obvious dislike of rain, as well.
In October 1902, Captain Robert von Beringe (1865-1940) shot two large apes during an expedition to establish the boundaries of German East Africa. One of the apes was recovered and sent to the Zoological Museum in Berlin, where Professor Paul Matschie (1861-1926) classified the animal as a new form of gorilla and named it Gorilla beringei after the man who discovered it. In 1925 Carl Akeley, a hunter from the American Museum of Natural History who wished to study the gorillas, convinced Albert I of Belgium to establish the Albert National Park to protect the animals of the Virunga mountains.
George Schaller began his 20 month observation of the Mountain Gorillas in 1959, subsequently publishing two books: The Mountain Gorilla and The Year of the Gorilla. Little was known about the life of the Mountain Gorilla before his research, which described its social organization, life history, and ecology. Following Schaller, Dian Fossey began what would become a 13 year study in 1967. Fossey made new observations, completed the first accurate census, and established active conservation practices, such as anti-poaching patrols. Ruth Keesling succeeded Fossey who was killed in 1985 and buried at the Karisoke Research Station in Rwanda. Keesling took over the Digit Fund renaming it the Dian Fossey Gorilla Fund Europe.
Mountain Gorillas are threatened by poaching, loss of habitat, and disease.
Poaching: Mountain Gorillas are not usually hunted for bushmeat, but they are frequently maimed or killed by traps and snares intended for other animals. They have been killed for their heads, hands, and feet, which are sold to collectors. Infants are sold to zoos, researchers, and people who want them as pets. The abduction of infants generally involves the loss of at least one adult, as members of a group will fight to the death to protect their young. Poaching for meat is particularly threatening in regions of political unrest. Most of the African great apes survive in areas of chronic insecurity, where automatic weapons are readily available and where there is a breakdown of law and order. The killing of mountain gorillas at Bikenge in Virunga National Park in January 2007 was a well documented case.
Habitat loss: The forests where Mountain Gorillas live are surrounded by rapidly increasing human settlement. The humans' need for land, food, and timber encroaches on the gorillas' habitat through roads, slash-and-burn agriculture, and logging. The resulting deforestation confines the gorillas to isolated forest islands. Some groups may raid crops for food, creating further animosity and retaliation.
Disease: Humans and gorillas are genetically similar enough that gorillas are vulnerable to many of the same diseases as humans. However, gorillas have not developed the immunities to resist human diseases, and infections could severely impact the population. Habituated groups that are visited by tourists have the greatest risk.
War and civil unrest: Civil wars and weak governments in central Africa, and in particular in the Congo, put conservation efforts at risk from local militias and government corruption
Conservation requires work at many levels, from local to international, and involves protection and law enforcement as well as research and education:
"Active conservation includes frequent patrols in wildlife areas to destroy poacher equipment and weapons, firm and prompt law enforcement, census counts in regions of breeding and ranging concentration, and strong safeguards for the limited habitat the animals occupy."
"Theoretical conservation seeks to encourage growth in tourism by improving existing roads that circle the mountains, by renovating the park headquarters and tourists' lodging, and by the habituation of gorillas near the park boundaries for tourists to visit and photograph."
Community-based conservation supports African ownership, provides education on the personal as well as environmental benefits of preserving protected areas, and encourages local people to take pride in and assume some of the responsibility for the protection of their parks.
In early 2007 two mountain gorillas were found dead. They appeared to be killed execution style by gunshots to the head.
Reasearchers recently have discovered that about 800,000 years ago that the mountain gorilla had evolved from the eastern gorilla
Subscribe to:
Posts (Atom)