The Primates. compiled by Dana Visalli. A male Mandrill

Transcription

1 The Primates compiled by Dana Visalli A male Mandrill Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment. Most primate species remain at least partly arboreal. There are a surprisingly large number of primates, or monkeys and their kin. The total number is variable, but settles in the range of approximately 325 species. The word primate comes from a Latin root meaning first rank or numeral uno, a reflection of ever-present anthropocentrism (human self-centeredness) of our species, which tends to judge nearby Homo sapiens (which means wise man ) as the pinnacle of the infinitely long evolutionary journey, while those Homo sapiens at a distance are often considered to be the other and the enemy and therefore not wise at all. Primates range in size from a tiny lemur in Madagascar called Madame Berthe s Mouse Lemur, which weighs one ounce, to the lowland gorillas in Africa, which weigh in at well over 400 pounds. Genetic studies indicate that the primate line originated about 85 million years ago, in the mid-cretaceous Period. New primate species are still being discovered. More than 25 species were taxonomically described in the decade of the 2000s and eleven have been described since Primates are characterized by large brains relative to other mammals, as well as an increased reliance on stereoscopic vision at the expense of smell, the dominant sensory system in most mammals. These features are more developed in monkeys and apes and noticeably less so in lorises and lemurs. Most primates have opposable thumbs and some have prehensile tails. Many species are sexually dimorphic, meaning males and females are markedly different in size; in primates males are typically larger than females (in contrast to raptors, in which females are typically larger). Depending on the species, adults may live in solitude, in mated pairs, or in groups of up to hundreds of members. Many primate species are now in danger of becoming extinct. The primary cause is deforestation, driven ultimately by human population growth and over-consumption of the Earth s resources. Additional pressure is placed on primate populations by humans hunting them to sell for food and pets. Monkeys and apes are popular sources of bush meat in Africa. Dana Visalli/dana@methownet.com/

2 Today, non-human primates are limited in their natural habitats primarily to the tropical and subtropical regions of the New and Old Worlds. They have never lived in Australia and most of the islands in the Pacific Ocean. However, the earliest primates also lived in North America and Europe beginning around million years ago. In primate evolution, there was a progressive reduction in nose size and in the olfactory areas of the brain. Lemurs are an exception; they are very much like the early primates 50 million years ago. As the primate nose progressively shrank in size over millions of years, there was a corresponding increase in visual capabilities. As much as 50% of the cerebral cortex in some species of monkeys is involved in visual processing. Many primates have color vision comparable to our own. All have binocular vision with fields of view that significantly overlap, resulting in true three dimensional depth perception or stereoscopic vision. At the same time, the field of view for peripheral vision was reduced. Compared to most other animals, primate brains are large relative to their body size. Those areas of the brain that are involved with controlling manual dexterity, eye-hand coordination, and stereoscopic vision have particularly expanded. These traits were probably selected by nature mostly due to their usefulness in traveling in trees. Most primates are diurnal, which is to say, they are active during the day and sleep at night. Generally, primates are highly social animals. Most of their waking hours are spent socializing with each other. This is made easier by complex vocalizations and visual displays. In addition, they regularly groom each other, thereby keeping clean and satisfying psychological needs at the same time. Grooming is a very pleasurable activity for primates, including humans. Primates have been very successful animals due largely to the fact that they are intelligent (have relatively flexible behavior; they are not completely dominated by genetic programming) and are opportunistic in obtaining food. Many species are omnivorous, though vegetable foods usually make up the bulk of calories consumed by most primate species because they are easier to obtain. By comparison, animals such as koalas and giant pandas are generally less successful because they are extremely limited in the kinds of foods that they can or will eat. Koalas subsist on the leaves of a few species of eucalyptus, and giant pandas primarily eat the shoots of a small number of bamboo species. If these food sources are not available, koalas and giant pandas die. Not surprisingly, their highly limited range of foods restricts where they can live. This is not the case with most primate species. Families of Primates 1. Dwarf & Mouse Lemurs- Family Cheirogaleidae ('genus name'): 34 species. This family lives exclusively on the island of Madagascar; they are the smallest of the primates. Dwarf and mouse lemurs are nocturnal and arboreal. They are excellent climbers and can also jump far, using their long tails for balance. When on the ground (a rare occurrence), they move by hopping on their hind legs. They spend the day in tree hollows or leaf nests. They are typically solitary, but sometimes live Madame Berthe s Mouse Lemur together in pairs. They are omnivores, eating fruits, flowers, leaves and sometimes nectar, as well as insects, spiders, and small vertebrates. Madame Berthe's mouse lemur (Microcebus berthae) is the smallest of the mouse lemurs and the smallest primate in the world; the average body length is 9.2 cm (3.6 in) and seasonal weight is around 30 g (1.1 oz). It was discovered in Lemurs- Family Lemuridae (Latin, 'spirits of the dead'): 21 species. This is one of five families commonly known as lemurs, all native to Madagascar. These animals were once thought to be the 2

3 evolutionary predecessors of monkeys and apes, but this is no longer considered correct. Lemurids are medium-sized arboreal primates, ranging from 32 to 56 cm (12-22 in) in length, excluding the tail, and weighing from 0.7 to 5 kg ( lbs). They have long, bushy tails and soft, woolly fur of varying coloration. Most species are highly agile, and regularly leap several metres between trees. 3. Sportive Lemurs- Family Lepilemuridae ('pretty lemur'): 26 species. Medium sized primates living only in Madagascar. They are strictly nocturnal, predominantly arboreal, and eat primarily leaves. They got their name from their leaping abilities. 4. Woolly Lemurs & Sifakas- Family Indriidae: 19 species. All species are arboreal, though they do come to the ground occasionally. When on the ground, they stand upright and move with short hops forward, with their arms held high. In the trees, though, they can make extraordinary leaps and are extremely agile, able to change direction from tree to tree. Like most leaf eaters they adjust for the low nutrient content of their food by long rests. Often they can be seen lying stretched on trees sunning themselves. Indrids live together in family federations from 2 to 15 animals, communicating with roars and also with facial expressions. Indrids are herbivores, eating mostly leaves, fruits and flowers. 5. Aye-Aye- Family Daubentoniidae: 1 species. The aye-aye (Daubentonia madagascariensis) is a lemur, a native to Madagascar that combines rodentlike teeth and a special thin middle finger to fill the same ecological niche as a woodpecker. It is the world's largest nocturnal primate, and is characterized by its unusual method of finding food; it taps on trees to find grubs, then gnaws holes in the wood using its forward slanting incisors to create a small hole in which it inserts its narrow middle finger to pull the grubs out. It is currently classified as Endangered, and a second species, Daubentonia robusta, appears to have become extinct at some point within the last 1000 years. A full-grown aye-aye is typically about three feet long with a tail as long as its body Ring-tailed Lemur Sportive Lemur Silky Sifaka (critically endangered) Aye-Aye 6. Lorises & Pottos-Family Lorisidae: 28 species. Lorisids live in tropical, central Africa as well as in south and southeast Asia. The are slim, nocturnal, arboreal primates that are either solitary or live in small family groups. The main diet of most lorisids consists of insects, but they also consume bird eggs and small vertebrates as well as fruits and sap. 7. Galagos- Galagidae: 19 species. Also known as Bushbabies. Small, nocturnal primates of Africa only. According to some accounts, the name "bush baby" comes from either the animal's cries or its appearance. Galagos have large eyes that give them good night vision, strong hind limbs, acute hearing, and long tails that help them balance. Their ears are batlike and allow them to track insects in the dark. They catch insects on the ground or snatch them out of the air. They are fast, agile creatures. As they bound through the thick bushes, they fold their delicate ears back to protect them. They have nails on most of their digits, except for the second toe of the 3 Red Slender Loris Garnett s Galago

4 hindfoot, which bears a 'toilet' claw for grooming. Their diet is a mixture of insects and other small animals, fruit, and tree gums. Young galagos are born with half-closed eyes and are initially unable to move about independently. After a few days, the mother carries the infant in her mouth, and places it on branches while feeding. Females may have singles, twins, or triplets and may become very aggressive. Each new born weighs less than half an ounce. The young are fed by the mother for six weeks and can feed themselves at two months. Females maintain their territory, but share them with their offspring. Brown Greater Galago Males leave their mothers' territories after puberty, but females remain, forming social groups consisting of closely related females and their young. Adult males maintain separate territories, which overlap with those of the female social groups; generally, one adult male mates with all the females in an area. Males who have not established such territories sometimes form small bachelor groups. At the end of the night, group members use a special rallying call and gather to sleep in a nest made of leaves, a group of branches, or a hole in a tree. 8. Tarsiers- Tarsiidae: ll species. This family was once more widespread, but all the species living today are found in the islands of Southeast Asia. Tarsiers are small animals with enormous eyes; each eyeball is approximately 16 mm in diameter and is as large as its entire brain. The unique cranial anatomy of the tarsier results from the need to balance their large eyes and heavy head so they are able to wait silently for nutritious prey. Tarsiers have an incredibly strong auditory sense because their auditory cortex is very distinct. Tarsiers also have very long hind limbs, due mostly to the extremely elongated tarsus Tarsier bones of the feet, from which the animals get their name. Tarsiers are the only extant entirely carnivorous primates: they are primarily insectivorous, and catch insects by jumping at them. They are also known to prey on birds, snakes, lizards, and bats. All tarsiers are considered vulnerable to extinction. 9. Marmosets & Tamarins- Family Callitrichidae (Greek, 'beautiful fur'): 43 species. A family of New World monkeys. They are all arboreal, relatively small and eat insects, fruit, and the sap or gum from trees; occasionally they will take small vertebrates. The marmosets rely quite heavily on tree exudates. Callitrichids typically live in small, territorial groups of about five or six animals. Their social organization is unique among primates and is called a "cooperative polyandrous group". This communal breeding system involves groups of multiple males and females, but only one female is reproductively Emperor Tamarin active. Females mate with more than one male and everyone shares the responsibility of carrying the offspring. They are the only primate group that regularly produces twins, which constitute over 80% of births in species that have been studied. Unlike other male primates, male callitrichids generally provide as much parental care as females. 10. Capuchins & Squirrel Monkeys- Family Cebidae (Gr, 'long-tailed monkey'): 26 species. One of 5 New World monkeys, these species are found throughout tropical and subtropical South and Central America. Cebid monkeys are arboreal animals that only rarely travel on the ground. They are generally small monkeys, ranging in size up to that of the Brown Capuchin, with a body length of 33 to 56 cm (13-22 in), and a weight of 2.5 to 3.9 kilograms (5-8/5 ;bs). They are somewhat variable in form and coloration, but all have the wide, flat, noses typical of New World Monkeys. They are different from marmosets as they have additional molar tooth and a prehensile tail. They are omnivorous, mostly eating fruit and insects, although the proportions of these foods vary greatly between species. Tufted Capuchin 4

5 11. Night or Owl Monkeys, also called Douroucoulis- Family Aotidae ('earless'): 11 species. The only nocturnal New World monkeys, they are native to Panama and much of tropical South America. Night monkeys have large brown eyes; the size improves their nocturnal vision, thus increasing their ability to be active at night. Their ears are rather difficult to see; this is why their genus name, Aotus (meaning "earless") was chosen. They are small, weighing from kg (1-3 lbs). Night monkeys make a notably wide variety of vocal sounds, with up to eight categories Nancy Ma s Night Monkey of distinct calls (gruff grunts, resonant grunts, screams, low trills, moans, gulps, sneeze grunts and hoots), and a frequency range of 190-1,950 Hz. Unusual among the New World monkeys, they are monochromats, that is, they have no colour vision, presumably because it is of no advantage given their nocturnal habits. They have a better spatial resolution at low light levels than other primates, which contributes to their ability to capture insects and move at night. Night monkeys live in family groups consisting of a mated pair and their immature offspring. Family groups defend territories by vocal calls and scent marking. The night monkey is socially monogamous, and all night monkeys form pair bonds. Only one infant is born each year. The male is the primary caregiver, and the mother only carries the infant for the first week or so of its life. This is believed to have developed because it increases the survival of the infant and reduces the metabolic costs on the female. 12. Titis, Sakis and Uakaris- Family Pitheciidae: 30 species. One of 5 families of New World monkeys, most species are native to the Amazonia region of Brazil, with some being found from Colombia in the north to Bolivia in the south. Pithecids are small to medium-sized monkeys, ranging from 23 cm in head-body length for the smaller titis, to cm for the uakaris. They are diurnal and arboreal animals, found in tropical forests from low-lying swamp to mountain slopes. They are predominantly herbivorous, eating mostly fruit and seeds, although some species will also eat a small number of insects. The uakaris and bearded White-faced Saki sakis are polygamous, living in groups of 8-30 individuals. Each group has multiple males, which establish a dominance hierarchy amongst themselves. The titis and sakis, by contrast, are monogamous and live in much smaller family groups. 13. Howler, Spider and Woolly Monkeys- Family Atelidae: 29 species. Atelids are generally larger monkeys and are found throughout the forested regions of Central and South America, from Mexico to northern Argentina. Howler monkeys are the largest members of the group, and the spider monkeys the smallest. They have long prehensile tails with a sensitive, almost hairless, tactile pad on the underside of the distal part. The tail is frequently used as 'fifth limb' while moving through the trees where they make their homes. They also have nails on their fingers and toes, enabling them to climb. Most species have predominantly dark Black Howler Monkeys brown, grey, or black fur, often with paler markings. These are arboreal and diurnal animals, with most species restricted to dense rain forest, although some howler monkey species are found in drier forests, or wooded savannah. They mainly eat fruit and leaves, although the smaller species, in particular, may also eat some small insects. Atelid monkeys are typically polygamous, and live in social groups with anything up to twenty five adults, depending on species. Where groups are relatively small, as is common amongst the howler monkeys, a single male monopolises a 'harem' of females, but larger groups will contain several males, with a clear hierarchy of dominance. 5

6 14. Old World Monkeys- Family Cercopithecidae (Gr, 'tail monkey'): 138 species. The Old World monkeys are native to Africa and Asia today, inhabiting a range of environments from tropical rain forest to savanna, shrubland and mountainous terrain, and are also known from Europe in the fossil record. However, a (possibly introduced) free-roaming group of monkeys still survives in Gibraltar (Europe) to this day. Old World monkeys include many of the most familiar species of nonhuman primates, such as baboons and macaques. Old World monkeys are medium to large Vervet Monkey in size, and range from arboreal forms, such as the colobus monkeys, to fully terrestrial forms, such as the baboons. The smallest is the talapoin, with a head and body cm in length, and weighing between 0.7 and 1.3 kilograms, while the largest is the male mandrill (the females of the species being significantly smaller), at around 70 cm in length, and weighing up to 50 kilograms. Old World monkeys are unlike apes in that most have tails (the family name means "tailed ape"), and unlike the New World monkeys in that their tails are never prehensile. Most Old World monkeys are at least partially omnivorous, but all prefer plant matter, which forms the bulk of their diet. Leaf monkeys are the most vegetarian, subsisting primarily on leaves, and eating only a small number of insects, while the other species are highly opportunistic, primarily eating fruit, but also consuming almost any food items available, such as flowers, leaves, bulbs and rhizomes, insects, snails, and even small vertebrates. In most species, daughters remain with their mothers for life, so that the basic social group among Old World monkeys is a matrilineal troop. Males leave Mandrill, rear view the group on reaching adolescence, and find a new troop to join. In many species, only a single adult male lives with each group, driving off all rivals, but others are more tolerant, establishing hierarchical relationships between dominant and subordinate males. Group sizes are highly variable, even within species, depending on the availability of food and other resources. 15. Gibbons or Lesser Apes- Family Hylobatidae (Gr, 'to wander the woods'): 16 species. Gibbons occur in tropical and subtropical rainforests from northeast India to Indonesia and north to southern China, including the islands of Sumatra, Borneo, and Java. Also called the lesser apes, gibbons differ from great apes (chimpanzees, gorillas, orangutans, bonobos and humans) in being smaller, exhibiting low sexual dimorphism, in not making nests, and in certain anatomical details in which they superficially more closely resemble monkeys than great apes do. But like all apes, Lar Gibbons gibbons evolved to become tailless. Gibbons also display pair-bonding, unlike most of the great apes. Gibbons are masters of their primary mode of locomotion, brachiation, swinging from branch to branch for distances of up to 15 m (50 ft), at speeds as high as 55 km/h (34 mph). They can also make leaps of up to 8 m (26 ft), and walk bipedally with their arms raised for balance. They are the fastest and most agile of all tree-dwelling, non-flying mammals. Some species have an enlarged throat sac, which inflates and serves as a resonating chamber when the animals call. This structure is enormous in a few species, equaling the size of the animal's head. Their voice is much more powerful than that of any human singer, although they are at best half a man's height. Gibbons are social animals. They are strongly territorial, and defend their boundaries with vigorous visual and vocal displays. The vocal element, which can often be heard for distances of up to 1 km (0.6 mi), consists of a duet between a mated pair, with their young sometimes joining in. In most species, males, and in some also females, sing solos to attract mates, as well as advertise their territories. The song can be used to identify not only which species of gibbon is singing, but also the area from which it comes. Most species are endangered, primarily due to degradation or loss of their forest habitats. 6 Agile Gibbon

7 16. Great Apes- Family Hominidae ('human'): 8 species. The Great Apes include four extant genera: the chimpanzees (Pan) with 2 species; gorillas (Gorilla) with 2 species; humans (Homo) with 1 species; and orangutans (Pongo) with 2 species. The ancestors of the Hominidae family speciated from those of the Hylobatidae family perhaps 15 million to 20 million years ago.molecular evidence suggests that between 8 and 4 million years ago, first the gorillas, and then the chimpanzees and bonobos (genus Pan) split off from the line leading to the humans; human DNA is approximately 98.4% identical to that of chimpanzees. A hominin is a member of the tribe Hominini; modern humans and their extinct relatives, although many scientists, including paleoanthropologists, continue to use the term hominid to mean humans and their direct and near-direct bipedal ancestors. Orangutans- genus Pongo- 3 species. Found only on the Islands of Sumatra and Borneo. A century ago there were about 230,000 orangutans; today there are about 60,000 Bornean orangutans, 15,000 Sumatran and 800 Tapanuliensis orangutans; the latter are a newly identified species (2017) and are considered critically endangered. The orangutans were the first apes to diverge from an ancestor common to all great apes. They are sexually dimorphic, with females reaching 45 kg (100 lbs) and males 115 kg (260 lbs). Fruit is the most important component of their diet, however they will also eat vegetation, honey, insects and bird eggs. Gorilla- genus Gorilla- 2 species; there are thought to be about 880 Mountain Gorillas ( subspecies of the eastern), 3800 eastern lowland gorillas and 150,000 wesetern lowland gorillas in existence. They are found only in central Africa. Gorillas grow to 2 meters (6.5 ft) tall and 180 kg (400 lbs). They are herbivores, eating mostly leaves. Gorillas are the second great ape to split away from a common ancestor, about 8 million years ago. Gorillas spend most of their time on ground, though they are adept in trees. Orangutan Male Mountain Gorilla A Chimpanzee cracking nuts Chimpanzees- genus Pan- 2 species. Chimps diverged from the human lineage about 7 million years ago; they differ from humans in genetic makeup by about 1%. There are thought to be about 200,000 chimps and 30,000 bonobos (which are endangered). Bonobos have only been recognized as a species apart from chimps since Male bonobos weigh about l00 pounds, females 70 pounds, both grow to about 3 8 tall. They are found only in the Democratic Republic of Congo (DRC). Bonobos are bipedal 5% of the time, usually when carrying food or other objects. They forage mostly in trees, sometimes on the ground. Chimpanzee males weigh 110 pounds and females weigh 100 pounds, they are about 4 tall. Chimpanzees use rocks as hammers to crack nuts and teach their young the technique. Chimps are the only other primate species besides Homo sapiens known to use male allegiance systems to systematically kill males in other groups. Bonobo Humans- Genus Homo- 1 species. Homo sapiens reached a population of 1 billion in 1800, after about 300,000 years on Earth, reached 2 billion in 1930, 3 billion in 1960, 4 billion in 1975, 5 billion in 1987, 6 billion in 1999, 7 billion in 2011, and is expected to reach 8 billion in A woman in the Surma tribe in Africa 7

8 The World s Most Endangered Primates 2018 data compiled by The Methow Naturalist/dana@methownet.com/ Hainan gibbon- Nomascus hainanus- Hainan Island, coastal China- remaining population: 28 Northern sportive lemur- Lepilemur septentrionalis- Madagascar- remaining population: 50 Eastern black crested gibbon- Nomascus nasutus- China & Vietnam- remaining population: 80 Blond capuchin- Cebus flavius- Brazil- remaining population: 180 Greater bamboo lemur- Prolemur simus- Madagascar- remaining populaton 125 Silky sifaka- Propithecus candidus- Madagascar- remaining population: 225 Northern brown howler- Alouatta guariba guariba- Brazil- remaining population: 225 Delacour's langur- Trachypithecus delacouri- Vietnam- remaining population: 225 White-headed langur- Trachypithecus poliocephalus- China, Vietnam- remaining population: 225 Tonkin snub-nosed monkey- Rhinopithecus avunculus- Vietnam- remaining population: 250 Cross River gorilla- Gorilla gorilla diehil- remaining population 250 Black-faced lion tamarin- Leontopithicus caissura- Brazil- remaining population: 400 Grey-shanked douc- Pygathrix cinerea- Vietnam- remaining population: 600 Tapanuli orangutan- Pongo tapanuliensis- Sumatara- remaining population 750 Mountain gorilla- Gorilla beringei beringei- Uganda, Rwanda, DNC- remaining population 880 Blue-eyed black lemur- Eulemur flavifrons- Madagascar- remaining population: 1000 Golden-rumped lion tamarin- Leontopithecus chrysopygus- east coast of Brazil- remaining population: 1000 Golden lion tamarin- Leontopithecus rosalia- ecoast of Brazil- remaining population: 1200 Tana River red colobus- Procolobus rufomitratus- Kenya- remaining population: 1200 Black crested gibbon- Nomascus concolor- China, Laos, Vietnam- remaining population: 1500 Eastern lowland gorilla- Gorilla beringei graueri- DRC- remaining population: 3800 Bioko red colobus- Piliocolobus pennantii- Equatorial Guinea- remaining population: 4800 Drill- Mandrillus leucophaeus- coastal Congo Basin- remaining population: 5000 Indri- Indri indri- Madagascar- remaining population: 5000 Sumatran organgutan- Pongo abelii- Sumatra- remainging population 6667 Pig-tailed langur- Simias concolor- Indonesia- remaining population: 8000 Madame Berthe's mouse lemur- Madagascar- Microcebus berthae- remaining population: 8000 Red ruffed lemur- Varecia rubra- Madagascar- remaining population: unknown Rondo dwarf galago- Galagoides rondoensis- Tanzania- remaining population: unknown Roloway monkey- Cercopithecus roloway- Ghana- remaining population: unknown Javan slow loris- Nycticebus javanicus- Java- remaining population: unknown Western purple-faced langur- Trachypithecus vetulus nestor- Sri Lanka- remaining population: unknown Pygmy tarsier- Tarsius pumilus- Indonesia- remaining population: unknown Brown spider monkey- Ateles hybridus- Columbia & Venezuela- remaining population: unknown Red ruffed lemur Tonkin Snub-nosed monkey Hainan gibbon Indri Black crested gibbon Gray-shanked Douc