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Assumptions about the problem need to be tested separately for each species.[96] The ring-tailed lemur, for instance, seems to be less prone to the disorder than other lemur species.[97]

Only eight species of lemur are known to be seed predators (granivores), but this may be under-reported since most observations only report fruit consumption and do not investigate whether the seeds are consumed as well. HP GC055515VH-A CPU FAN

These lemurs include some indriids, such as the diademed sifaka(Propithecus diadema), the golden-crowned sifaka (Propithecus tattersalli), the indri,[11][67] and the aye-aye. The aye-aye, which specializes in structurally defended resources, can chew through Canarium seeds, which are harder than the seeds that New World monkeys are known to break open.[49] At least 36 genera from 23 families of plants are targeted by lemur seed predators.[93] HP GC057015VH-A CPU FAN

Inflorescences (clusters of flowers) of at least 60 plant families are eaten by lemurs ranging in size from the tiny mouse lemurs to the relatively large ruffed lemurs. If the flowers are not exploited, sometimes the nectar is consumed (nectarivory) along with the pollen (palynivory). At least 24 native species from 17 plant families are targeted for nectar or pollen consumption.[93]

Bark and plant exudates such as tree sap are consumed by a few lemur species. HP GC057514VH-A CPU FAN

The exploitation of exudates has been reported in 18 plant species and only in the dry regions in the south and west of Madagascar. Only the Masoala fork-marked lemur (Phaner furcifer) and Coquerel's giant mouse lemur regularly consume tree sap. Bark has never been reported as an important food item in lemur diets, but at least four species eat it: the aye-aye, the red-tailed sportive lemur(Lepilemur ruficaudatus), the common brown lemur (Eulemur fulvus), and Verreaux's sifaka (Propithecus verreauxi). HP KDB0505HB CPU FAN

Most bark feeding is directly linked to exudate feeding, except for the aye-aye's bark feeding on Afzelia bijuga (genus Afzelia) at Nosy Mangabe in the northeast.[93]

Soil consumption (geophagy) has also been reported and likely helps with digestion, provides minerals and salts, and helps absorb toxins. HP KDB05605HB CPU FAN

Sifakas have been observed eating soil from termite mounds, possibly adding beneficial intestinal flora to aid the digestion of cellulose from their folivorous diet.

Lemurs are social and live in groups that usually include less than 15 individuals.[11] Observed social organization patterns include "solitary but social", "fission-fusion", "pair bonds", and "multi-male group".[98] HP KSB0605HB CPU FAN

Nocturnal lemurs are mostly solitary but social, foraging alone at night but often nesting in groups during the day. The degree of socialization varies by species, gender, location, and season.[26][35] In many nocturnal species, for instance, the females, along with their young, will share nests with other females and possibly one male, whose larger home range happens to overlap one or more female nesting groups. HP KSB06105HA CPU FAN

Insportive lemurs and fork-marked lemurs, one or two females may share a home range, possibly with a male. In addition to sharing nests, they will also interact vocally or physically with their range-mate while they forage at night.[35] Diurnal lemurs exhibit many of the social systems seen in monkeys and apes,[11][35]living in relatively permanent and cohesive social groups. Multi-male groups are the most common, just as they are in most anthropoid primates. HP MCF-811AM05 CPU FAN

True lemursutilize this social system, often living in groups of ten or less. Ruffed lemurs have been shown to live in fission-fusion societies,[35] and Indri forms pair bonds.

Some lemurs exhibit female philopatry, where females stay within their natal range and the males migrate upon reaching maturity, and in other species both sexes will migrate.[11] HP MCF-W13BM05 CPU FAN

In some cases, female philopatry may help explain the evolution of female-bonded multi-male groups, such as those of the ring-tailed lemur, Milne-Edwards' sifaka (Propithecus edwardsi), and the Verreaux's sifaka. Their ancestors may have been more solitary, with females that lived in mother-daughter pairs (or dyads). Over time, these dyads may have allied themselves with other neighboring mother-daughter dyads in order to defend more distributed resources in a wide home range. HP 540 CPU FAN

If this is true, then multi-male groups in lemurs may differ fundamentally in their internal structure from those incatarrhine primates (Old World monkeys and apes).[99]

The presence of female social dominance sets lemurs apart from most other primates and mammals;in most primate societies, males are dominant unless females band together to form coalitions that displace them. However, many Eulemur species are exceptions and the greater bamboo lemur (Prolemur simus) does not exhibit female dominance.[102] HP 550 CPU FAN

When females are dominant within a group, the way they maintain dominance varies. Ring-tailed lemur males act submissively with or without signs of female aggression. Male crowned lemurs (Eulemur coronatus), on the other hand, will only act submissively when females act aggressively towards them. Female aggression is often associated with, but not limited to, feeding.[103] HP 6445B Series CPU FAN

There have been many hypotheses that have attempted to explain why lemurs exhibit female social dominance while other primates with similar social structures do not,[11][100] but no consensus has been reached after decades of research. The dominant view in the literature states that female dominance is an advantageous trait given the high costs of reproduction and the scarcity of resources available.[100] HP 6520s CPU FAN

Indeed, female dominance has been shown to be linked to increased maternal investment.[101] However, when reproductive costs and extreme seasonality of resources were compared across primates, other primates demonstrated male dominance under conditions that were similar to or more challenging than those faced by lemurs. In 2008, a new hypothesis revised this model using simple game theory. HP 6545B Series CPU FAN

It was argued that when two individuals were equally matched in fighting capacity, the one with the most need would win the conflict since it would have the most to lose. Consequently, the female, with higher resource needs for pregnancy, lactation, and maternal care, was more likely to win in resource conflicts with equally sized males. This, however, assumed monomorphism between sexes.[100] The following year, a new hypothesis was proposed to explain monomorphism, HP 6720 CPU FAN

stating that because most female lemurs are only sexually receptive for a day or two each year, males can utilize a more passive form of mate guarding: copulatory plugs, which block the female reproductive tract, preventing other males from successfully mating with her, and thus reducing the need for aggression and the evolutionary drive for sexual dimorphism.

In general, levels of agonism (or aggression) tend to correlate with relative canine height. HP 6820s CPU FAN

The ring-tailed lemur has long, sharp upper canine teeth in both sexes, and it also exhibits high levels of agonism. The Indri, on the other hand, has smaller canines and exhibits lower levels of aggression.[29] When neighboring groups of the same species defend their territories, the conflict can take the form of ritualized defense. In sifakas, these ritualized combats involve staring, growling, scent-marking, and leaping to occupy certain sections of the tree. HP EliteBook 6930P Series CPU FAN

The indri defends its home range with ritualized "singing" battles.[11]

Like other primates, lemurs groom socially (allogroom) to ease tensions and solidify relationships. They groom in greeting, when waking up, when settling in for sleep, between mother and infant, in juvenile relations, and for sexual advances.[104]Unlike anthropoid primates, who part the fur with the hands and pick out particles with the fingers or mouth, HP EliteBook 8530 Series CPU FAN

lemurs groom with their tongue and scraping with their toothcomb. Despite the differences in technique, lemurs groom with the same frequency and for the same reasons as anthropoids.

The biological rhythm can vary from nocturnal in smaller lemurs to diurnal in most larger lemurs. Diurnality is not seen in any other prosimian.[26]Cathemerality, where an animal is active sporadically both day and night, occurs among some of the larger lemurs. HP EliteBook 8530p Series CPU FAN

Few if any other primates exhibit this sort of activity cycle,[105] either regularly or irregularly under changing environmental conditions.[11] The most heavily studied cathemeral lemurs are the true lemurs.[39][106] Although the mongoose lemur (E. mongoz) is the best-documented example, every species in the genus studied has shown some degree of cathemeral behavior,[69] although night activity is often restricted by light availability and moon periodicity.[12] HP EliteBook 8530w Series CPU FAN

This type of behavior was first documented in the 1960s in true lemur species as well as other Lemuridae species, such as ruffed lemurs and bamboo lemurs. Initially described as "crepuscular" (active at dawn and dusk), anthropologist Ian Tattersall stimulated additional research and coined the new term "cathemeral",[105] although many non-anthropologists prefer the terms "circadian" or "diel".[12] DELL Inspiron N3010 Series CPU FAN

In order to conserve energy and water in their highly seasonal environment,[90][107] mouse lemurs and dwarf lemurs exhibit seasonal behavioral cycles of dormancywhere the metabolic rate and body temperature are lowered. They are the only primates known to do so.[90] They accumulate fat reserves in their hind legs and the base of their tail before the dry winter season, when food and water are scarce,[27][91] DELL Inspiron N4010 Series CPU FAN
can exhibit daily and prolonged torpor during the dry season. Daily torpor constitutes less than 24 hours of dormancy, whereas prolonged torpor averages two weeks in duration and signals hibernation.[90] Mouse lemurs have been observed experiencing torpor that lasts for several consecutive days, but dwarf lemurs are known to hibernate for six to eight months every year,[26][27][92]particularly on the west coast of Madagascar.[107] DELL Latitude 100L CPU FAN

Dwarf lemurs are the only primates known to hibernate for extended periods.[90][108] Unlike other hibernating mammals from temperate regions, which have to awaken regularly for a few days, dwarf lemurs experience five months of continuous deep hibernation (May through September). Before and after this deep hibernation, there are two months (April and October) of transition, where they will forage on a limited basis to reduce demands on their fat reserves.[107] DELL Latitude 120L Series CPU FAN
Unlike any other hibernating mammal, the body temperature of hibernating dwarf lemurs will fluctuate with the ambient temperature rather than remaining low and stable.

Other lemurs that do not exhibit dormancy conserve energy by selecting thermoregulated microhabitats (such as tree holes), sharing nests, and reducing exposed body surfaces, such as by hunched sitting and group huddling. Also, the ring-tailed lemur, ruffed lemurs, and sifakas are commonly seen sunning, thus using solar radiation to warm their bodies instead of metabolic heat. DELL Latitude 131L Series CPU FAN

Locomotor behavior in lemurs, both living and extinct, is highly varied and its diversity exceeds that of anthropoids.[35] Locomotor postures and behaviors have included vertical clinging and leaping (including saltatory behavior), seen in indriids and bamboo lemurs;[35][63] slow (loris-like) arboreal quadrupedal locomotion, once exhibited by Mesopropithecus;[109] fast arboreal quadrupedal locomotion, seen in true lemurs and ruffed lemurs;[ DELL Latitude C500 CPU FAN
partially terrestrial quadrupedal locomotion, seen in the ring-tailed lemur; highly terrestrial quadrupedal locomotion, once exhibited by monkey lemurs such as Hadropithecus;[35] and sloth-like suspensory locomotion, once exhibited by many of the sloth lemurs, such as Palaeopropithecus.[11][35] The Lac Alaotra gentle lemur(Hapalemur alaotrensis) has even been reported to be a good swimmer.[11] DELL Latitude C540 CPU FAN
Sometimes these locomotor types are lumped together into two main groups of lemurs, the vertical clingers and leapers and the arboreal (and occasionally terrestrial) quadrupeds.[61]

The jumping prowess of the indriids have been well documented and are popular among ecotourists visiting Madagascar.[111] Using their long, powerful back legs, they catapult themselves into the air and land in an upright posture on a nearby tree, with both hands and feet tightly gripping the trunk.[13DELL Latitude C600 CPU FAN

] Indriids can leap up to 10 m (33 ft) rapidly from tree trunk to tree trunk,[13][66] an ability referred to as "ricochetal leaping".[76] Verreaux's sifaka (Propithecus verreauxi) manages to do this in the spiny forests of southern Madagascar. It is unknown how it avoids impaling its palms on the thorn-covered trunks of large plants such asAlluaudia.[13] When distances between trees are too great, DELL Latitude C610 CPU FAN
sifakas will descend to the ground and cross distances more than 100 m (330 ft) by standing upright and hopping sideways with the arms held to the side and waving up and down from chest to head height, presumably for balance.[13][66] This is sometimes described as a "dance-hop".

Lemur communication can be transmitted through sound, sight, and smell (olfaction). DELL Latitude C640 CPU FAN
The ring-tailed lemur, for instance, uses complex though highly stereotyped behaviors such as scent-marking and vocalizations.[87] Visual signals are probably the least used by lemurs, since they lack many of the muscles used in common primate facial expressions.[85] Given their poor vision, whole-body postures are probably more noticeable. However, the ring-tailed lemur has demonstrated distinct facial expressions including a threat stare, pulled back lips for submission, and pulled back ears along with flared nostrils during scent-marking.[87] DELL Latitude C800 Series CPU FAN
This species has also been observed using yawns as threats.[112][113] Their ringed tails also communicate distance, warn off neighboring troops, and help locate troop members.[87] Sifakas are known to exhibit an open-mouth play face[114] as well as a submissive teeth-baring grimace used in agonistic interactions.

Olfaction is particularly important to lemurs,[11] except for the indri, which lacks most common lemur scent glands and has a greatly reduced olfactory region in the brain.[76] DELL Latitude C810 Series CPU FAN
Olfaction can communicate information about age, sex, reproductive status, as well as demarcate the boundaries of a territory. It is most useful for communication between animals that rarely encounter each other.[49] Small, nocturnal lemurs mark their territories with urine, while the larger, diurnal species use scent glands located on various parts of their anatomy. The ring-tailed lemur engages in "stink fights" by rubbing its tail across scent glands on its wrists, and then flicking its tail at other male opponents. DELL Latitude C840 Series CPU FAN
Some lemurs defecate in specific areas, otherwise known as latrine behavior. Although many animals exhibit this behavior, it is a rare trait among primates. Latrine behavior can represent territorial marking and aid in interspecies signaling.[12]

Compared to other mammals, primates in general are very vocal, and lemurs are no exception.[12] Some lemur species have extensive vocal repertoires, including the ring-tailed lemur and ruffed lemurs.[87][115] DELL Latitude D400 Series CPU FAN
Some of the most common calls among lemurs are predator alarm calls. Lemurs not only respond to alarm calls of their own species, but also alarm calls of other species and those of non-predatory birds. The ring-tailed lemur and a few other species have different calls and reactions to specific types of predators.[35] DELL Latitude D410 Series CPU FAN
With mating calls, it has been shown that mouse lemurs that cannot be discerned visually respond more strongly to the calls of their own species, particularly when exposed to the calls of other mouse lemurs that they would encounter normally within their home range.[70] Lemur calls can also be very loud and carry long distances. Ruffed lemurs use several loud calls that can be heard up to 1 km (0.62 mi) away on a clear, calm day.[115] DELL Latitude D420 CPU FAN
The loudest lemur is the indri, whose calls can be heard up to 2 km (1.2 mi) or more[50][60] and thus communicate more effectively the territorial boundaries over its 34 to 40 hectares (0.13 to 0.15 sq mi) home range.[76] Both ruffed lemurs and the indri exhibit contagious calling, where one individual or group starts a loud call and others within the area join in.[60][115] The song of the indri can last 45 seconds to more than 3 minutes and tends to coordinate to form a stable duet comparable to that of gibbons.[60][65] DELL Latitude D430 CPU FAN

Tactile communication (touch) is mostly used by lemurs in the form of grooming, although the ring-tailed lemur also clumps together to sleep (in an order determined by rank), reaches out and touches adjacent members, and cuffs other members. Reaching out and touching another individual in this species has been shown to be a submissive behavior, done by younger or submissive animals towards older and more dominant members of the troop. DELL Latitude D500 Series CPU FAN
Allogrooming, however, appears to occur more frequently between higher ranking individuals, a shared trait with other primate species.[116] Unlike anthropoid primates, lemur grooming seems to be more intimate and mutual, often directly reciprocated. Anthropoids, on the other hand, use allogrooming to manage agonistic interactions.[117] The ring-tailed lemur is known to be very tactile, spending between 5 and 11% of its time grooming. DELL Latitude D505 Series CPU FAN

All lemurs experience some predation pressure.[118] Common defenses against predation include the use of alarm calls and predator mobbing,[119] mostly among diurnal lemurs.[35] The leaping abilities of lemurs may have evolved for predator avoidance rather than for travel, according to a study in kinematics.[120] Nocturnal lemurs are difficult to see and track at night and decrease their visibility by foraging alone. DELL Latitude D510 Series CPU FAN
They also try to avoid predators by using concealing sleeping locations, such as nests, tree holes, or dense vegetation,[35] Some may also avoid areas frequented by predators by detecting the smell of their feces.[121] and alternating between multiple sleeping locations.[27] Even torpor and hibernation states among cheirogaleids may be partly due to high levels of predation.[118] DELL Latitude D531 CPU FAN
Infants are protected while foraging by either leaving them in the nest or by stashing them in a hidden location, where the infant remains immobile in the absence of the parent.[35]

Diurnal lemurs are visible during the day, so many live in groups, where the increased number of eyes and ears helps aid in predator detection. Diurnal lemurs use and respond to alarm calls, even those of other lemur species and non-predatory birds. DELL Latitude D600 Series CPU FAN
The ring-tailed lemur has different calls and reactions to different classes of predators, such as predatory birds, mammals, or snakes.[35] Some lemurs, such as the indri, use crypsis to camouflage themselves. They are often heard but difficult to see in the trees due to the dappled light, earning them the reputation of being "ghosts of the forest".

Except for the aye-aye and the Lac Alaotra gentle lemur, lemurs are seasonal breeders with very short mating and birth seasons influenced by the highly seasonal availability of resources in their environment. DELL Latitude D610 Series CPU FAN
Mating seasons usually last less than three weeks each year,[35] with the female vagina opening up only during a few hours or days of her most receptive time of estrus.[83] These narrow windows for reproduction and resource availability appear to relate to their short gestation periods, rapid maturation, and low basal metabolic rates, as well as the high energy costs of reproduction for females. DELL Latitude D620 CPU FAN
This may also relate to the relatively high mortality rate among adult females and the higher proportion of adult males in some lemur populations—both unusual traits among primates. In both the aye-aye and Lac Alaotra gentle lemur, birth (parturition) occurs over a six-month period.[11]

Lemurs time their mating and birth seasons so that all weaning periods are synchronized to match the time of highest food availability.[ DELL Latitude D630 CPU FAN
Weaning occurs either before or shortly after the eruption of the first permanent molars in lemurs.[29] Mouse lemurs are able to fit their entire breeding cycle into the wet season, whereas larger lemurs, such as sifakas, must lactate for two months during the dry season.[94] Infant survival in some species, such as Milne-Edwards' sifaka, has been shown to be directly impacted by both environmental conditions and the rank, age, and health of the mother. DELL Latitude D800 Series CPU FAN
The breeding season is also affected by geographical location. For example, mouse lemurs give birth between September and October in their native habitat in the southern hemisphere, but from May through June in the captive settings in the northern hemisphere.

Scent factors heavily into lemur reproduction. Scent-marking activity escalates during the mating season. Pheromones may coordinate reproductive timing for females coming into estrus.[83] DELL Latitude D810 Series CPU FAN
Mating can be either monogamous or promiscuous for both males and females, and mating can include individuals from outside the group.[11][35] Monogamous lemurs include the red-bellied lemur (Eulemur rubriventer) and the mongoose lemur (E. mongoz), although the mongoose lemur has been observed mating outside of its pair bond.[35]Monogamy is most common among nocturnal species, DELL Latitude D820 CPU FAN
although some exhibit scramble competition, sexual suppression of subordinates, or competitions between males that avoid direct fighting.[29] In mouse lemurs, males utilize sperm plugs, developed enlarged testesduring the mating season, and develop size dimorphism (likely due to the enlarged testes). These indicate a mating system known asscramble competition polygyny, where males cannot defend females or the resources that might attract them.[122] DELL Latitude D830 CPU FAN

The gestation period varies within lemurs, ranging from 9 weeks in mouse lemurs and 9–10 weeks in dwarf lemurs to 18–24 weeks in other lemurs.[83] The smaller, nocturnal lemurs, such as mouse lemurs, giant mouse lemurs, and dwarf lemurs, usually give birth to more than one infant, whereas the larger, nocturnal lemurs, such as fork-marked lemurs, sportive lemurs, and the aye-aye usually have one offspring.[26] DELL Latitude E4200 Series CPU FAN
Dwarf and mouse lemurs have up to four offspring, but both average only two. Ruffed lemurs are the only large, diurnal lemurs to consistently give birth to two or three offspring. All other lemurs have single births. Multiple births in lemurs are normally fraternal, and are known to occur in every five to six births in species such as the ring-tailed lemur and someEulemur.[83]

After the offspring are born, lemurs either carry them around or stash them while foraging. DELL Latitude E4300 Series CPU FAN
When transported, the infants either cling to the mother's fur or are carried in the mouth by the scruff. In some species, such as bamboo lemurs, infants are carried by mouth until they are able to cling to their mother's fur.[123] Species that park their offspring include nocturnal species (e.g. mouse lemurs, sportive lemurs, and dwarf lemurs), bamboo lemurs, and ruffed lemurs.[26][123] In the case of the ruffed lemurs, the young are altricial and the mothers build nests for them, much like the smaller, DELL LATITUDE E4310 Series CPU FAN
nocturnal lemur species.[11] Woolly lemurs are unusual for nocturnal lemurs because they live in cohesive family groups and carry their single offspring with them rather than parking them.[63][64] Alloparenting (multiple or group parenting) has been reported in all lemur families except the sportive lemurs and aye-aye. Allonursing is also known to occur in several lemur groups.[124] Even males have been observed caring for infants in species such as the red-bellied lemur, mongoose lemur,[69DELL Latitude E5400 CPU FAN] eastern lesser bamboo lemur, silky sifaka,[124] fat-tailed dwarf lemur,[125] and ruffed lemurs.[126]

Yet another trait that sets most lemurs apart from anthropoid primates is their long lifespan together with their high infant mortality.[94] Many lemurs, including the ring-tailed lemur, have adapted to a highly seasonal environment, which has affected their birthrate, maturation, and twinning rate (r-selection). DELL Latitude E5500 CPU FAN
This helps them to recover rapidly from a population crash.[87] In captivity, lemurs can live twice as long as they do in the wild, benefiting from consistent nutrition that meets their dietary requirements, medical advancements, and improved understanding of their housing requirements. In 1960, it was thought that lemurs could live between 23 and 25 years. We now know that the larger species can live for more than 30 years without showing signs of aging (senescence) and still be capable of reproduction.

Lemurs have traditionally been regarded as being less intelligent than anthropoid primates,[127] DELL Latitude E6400 Series CPU FAN
with monkeys and apes often described as having more cunning, guile, and deceptiveness.[13] Many lemur species, such as sifakas and the ring-tailed lemur, have scored lower on tests designed for monkeys while performing as well as monkeys on other tests.[13][104] These comparisons may not be fair since lemurs prefer to manipulate objects with their mouths (rather than their hands) and only take interest in objects when in captivity.[104] DELL Latitude E6410 CPU FAN
Recent studies have shown that lemurs exhibit levels of technical intelligence on par with many other primates, although they manipulate objects less often.[128] Tool use has not been witnessed by lemurs in the wild, although in captivity the common brown lemur and the ring-tailed lemur have been demonstrated to be able to understand and use tools.[12]

A few lemurs have been noted to have relatively large brains. DELL Latitude E6410 Series CPU FAN
The extinct Hadropithecus was as large as a large male baboon and had a comparably sized brain, giving it the largest brain size relative to body size among all prosimians.[129] The aye-aye also has a large brain-to-body ratio, which may indicate a higher level of intelligence.[39] However, despite having a built-in tool in the form of its thin, elongated middle finger, which it uses to fish for insect grubs, the aye-aye has tested poorly in the use of extraneous tools. DELL Latitude E6420 CPU FAN

Madagascar not only contains two radically different climatic zones, the rainforests of the east and the dry regions of the west,[11] but also swings from extended drought to cyclone-generated floods.[130] These climatic and geographical challenges, along with poor soils, low plant productivity, wide ranges ofecosystem complexity, and a lack of regularly fruiting trees (such as fig trees) have driven the evolution of lemurs' immense morphological and behavioral diversity .DELL Latitude E6500 CPU FAN
Their survival has required the ability to endure the persistent extremes, not yearly averages.

Lemurs have either presently or formerly filled the ecological niches normally occupied by monkeys, squirrels, woodpeckers, and grazing ungulates.[13] With the diversity of adaptations for specific ecological niches, habitat selections among lemur families and some genera are often very distinct, thus minimizing competition.[11] DELL Latitude E6500 Series CPU FAN
In nocturnal lemurs from the more seasonal forests in the west, up to five species can coexist during the wet season due to high food abundance. However, to endure the extreme dry season, three of the five species utilize different dietary patterns and their underlying physiological traits to allow them to coexist: fork-marked lemurs feed on tree gum, sportive lemurs feed on leaves, and giant mouse lemurs sometimes feed on insect secretions. DELL Latitude E6510 CPU FAN
The other two species, the gray mouse lemur and the fat-tailed dwarf lemur (Cheirogaleus medius), avoid competition through reduced activity. The gray mouse lemur uses bouts of torpor, while the fat-tailed dwarf lemur hibernates completely.[26]Similarly, on the east coast entire genera focus on specific food to avoid too much niche overlap. True lemurs and ruffed lemurs are frugivorous, indriids are folivorous, and bamboo lemurs specialize in bamboo and other grasses. DELL Latitude E6510 Series CPU FAN
Once again, seasonal dietary differences as well as subtle differences in substrate preferences, forest strata used, activity cycle, and social organization enable lemur species to coexist, although this time the species are more closely related and have similar niches.[11] A classic example involves resource partitioning between three species of bamboo lemur that live in close proximity in small forested areas: the golden bamboo lemur, the greater bamboo lemur, and the eastern lesser bamboo lemur (Hapalemur griseus). DELL Precision M4400 Series CPU FAN
Each utilizes either different species of bamboo, different parts of the plant, or different layers in the forest.[13][54] Nutrient and toxin content (such as cyanide) help regulate food selection,[11] though seasonal food preferences are also known to play a role.[54]

Dietary regimes of lemurs include folivory, frugivory, and omnivory, with some being highly adaptable while others specialize on foods such as plant exudates (tree gum) and bamboo.[131] DELL Precision M4500 CPU FAN
In some cases, lemur feeding patterns directly benefit the native plant life. When lemurs exploit nectar, they may act as pollinators as long as the functional parts of the flower are not damaged.[93] In fact, several unrelated Malagasy flowering plants demonstrate lemur-specific pollination traits, and studies indicate that some diurnal species, such as the red-bellied lemur and the ruffed lemurs, act as major pollinators.[11] DELL Precision M6400 Series CPU FAN
Two examples of plant species that rely on lemurs for pollination include traveller's palm (Ravenala madagascariensis)[57] and a species of legume-like liana, Strongylodon cravieniae.[11] Seed dispersalis another service lemurs provide. After passing through the lemur gut, tree and vine seeds exhibit lower mortality and germinate faster.[94] Latrine behavior exhibited by some lemurs may help improve soil quality and facilitate seed dispersal.[12] DELL Precision M65 CPU FAN
Because of their importance in maintaining a healthy forest, frugivorous lemurs may qualify as keystone mutualists.[94]

All lemurs, particularly the smaller species, are affected by predation[26][118] and they are important prey items for predators.[122] Humans are the most significant predator of diurnal lemurs, despite taboos that occasionally forbid the hunting and eating of certain lemur species.[11] DELL Precision M70 Series CPU FAN
Other predators include native euplerids, such as the fossa, feral cats, domestic dogs, snakes, diurnal birds of prey, owls, and crocodiles. Extinct giant eagles, including one or two species from the genus Aquila and the giant Malagasy crowned eagle (Stephanoaetus mahery), as well as the giant fossa (Cryptoprocta spelea), previously also preyed on lemurs, perhaps including the giant subfossil lemurs or their subadult offspring.[26][118] DELL Precision M90 CPU FAN
The existence of these extinct giants suggests that predator-prey interactions involving lemurs were more complex than they are today.[11] Today, predator size only restricts owls to the smaller lemurs, usually 100 g (3.5 oz) or less, while the larger lemurs fall victim to the larger diurnal birds of prey, such as the Madagascar harrier-hawk (Polyboroides radiatus) and the Madagascar buzzard (Buteo brachypterus). DELL Pricision M6300 CPU FAN

Similarities that lemurs share with anthropoid primates, such as diet and social organization, along with their own unique traits, have made lemurs the most heavily studied of all mammal groups on Madagascar.[11][59] Research often focuses on the link between ecology and social organization, but also on their behavior and morphophysiology (the study of anatomy in relation to function).[11] Studies of their life-history traits, behavior and ecology help understanding of primate evolution, since they are thought to share similarities with ancestral primates. DELL Studio 1435 CPU FAN

Lemurs have been the focus of monographic series, action plans, field guides, and classic works in ethology.[59] However, few species have been thoroughly studied to date, and most research has been preliminary and restricted to a single locality.[11] Only recently have numerous scientific papers been published to explain the basic aspects of behavior and ecology of poorly known species. Field studies have given insights on population dynamics and evolutionary ecology of most genera and many species.[59] DELL Studio 1450 CPU FAN
Long-term research focused on identified individuals is in its infancy and has only been started for a few populations. However, learning opportunities are dwindling as habitat destruction and other factors threaten the existence of lemur populations across the island.

Lemurs are mentioned in sailors' voyage logs as far back as 1608 and in 1658 that at least seven lemur species were described in detail by the French merchant, DELL Studio 1457 CPU FAN
Étienne de Flacourt, who may also have been the only westerner to see and chronicle the existence of a giant (now extinct) lemur, which he called the tretretretre. Around 1703 merchants and sailors began bringing lemurs back to Europe, at which time James Petiver, an apothecary in London, described and illustrated the mongoose lemur. Starting in 1751, the London illustrator George Edwards began describing and illustrating some lemur species, of which a few were included in various editions of Systema Naturae by Carl Linnaeus. DELL Studio 1458 CPU FAN
In the 1760s and 1770s, French naturalists Georges-Louis Leclerc, Comte de Buffon and Louis-Jean-Marie Daubenton began describing the anatomy of several lemur species. The first traveling naturalist to comment on lemurs was Philibert Commerçon in 1771, although it was Pierre Sonnerat who recorded a greater variety of lemur species during his travels.[130][132]

During the 19th century, there was an explosion of new lemur descriptions and names, DELL Studio 1535 Series CPU FAN
which later took decades to sort out. During this time, professional collectors gathered specimens for museums, menageries, and cabinets. Some of the major collectors were Johannes Hildebrandt and Charles Immanuel Forsyth Major. From these collections, as well as increasing observations of lemurs in their natural habitats, museum systematists including Albert Günther and John Edward Gray continued to contribute new names for new lemur species. DELL Studio 1536 Series CPU FAN
However, the most notable contributions from this century includes the work of Alfred Grandidier, a naturalist and explorer who devoted himself to the study of Madagascar's natural history and local people. With the help of Alphonse Milne-Edwards, most of the diurnal lemurs were illustrated at this time. However, lemur taxonomic nomenclature took its modern form in the 1920s and 1930s, being standardized by Ernst Schwarz in 1931.[130][132] DELL Studio 1537 Series CPU FAN

Although lemur taxonomy had developed, it was not until the 1950s and 1960s that the in-situ (or on-site) study of lemur behavior and ecology began to blossom.Jean-Jacques Petter and Arlette Petter-Rousseaux toured Madagascar in 1956 and 1957, surveying many of its lemur species and making important observations about their social groupings and reproduction. In 1960, the year of Madagascar's independence, David Attenborough introduced lemurs to the West with a commercial film. DELL Studio 1555 Series CPU FAN
Under the guidance of John Buettner-Janusch, who founded the Duke Lemur Center in 1966, Alison Jolly traveled to Madagascar in 1962 to study the diet and social behavior of the ring-tailed lemur and Verreaux's sifaka at Berenty Private Reserve. The Petters and Jolly spawned a new era of interest in lemur ecology and behavior and were shortly followed by anthropologists such as Alison Richard, Robert Sussman, Ian Tattersall, and many others. DELL Studio 17 CPU FAN
Following the political turmoil of the mid-1970s and Madagascar's revolution, field studies resumed in the 1980s, thanks in part to the renewed involvement of the Duke Lemur Center under the direction of Elwyn Simons and the conservation efforts of Patricia Wright.[11][130][132] In the decades that followed, huge strides have been made in lemur studies and many new species have been discovered.[4] DELL Studio 1735 CPU FAN

Ex situ research (or off-site research) is also popular among researchers looking to answer questions that are difficult to test in the field. For example, efforts to sequence the genome of the gray mouse lemur will help researchers understand which genetic traits set primates apart from other mammals and will ultimately help understand what genomic traits set humans apart from other primates.[30] One of the foremost lemur research facilities is the Duke Lemur Center (DLC) in Durham, North Carolina. DELL Studio 1736 CPU FAN
It maintains the largest captive lemur population outside of Madagascar, which it maintains for non-invasive research andcaptive breeding.[133] Many important research projects have been carried out there, including studies of lemur vocalizations,[134] basic locomotor research,[135]the kinematics of bipedalism,[136] the effects of social complexity transitive reasoning,[137] and cognition studies involving a lemur's ability to organize and retrieve sequences from memory.[138] DELL Studio 1737 CPU FAN
Other facilities, such as the Lemur Conservation Foundation, located near Myakka City, Florida, have also hosted research projects, such as one that looked at lemurs' ability to preferentially select tools based on functional qualities.

Lemurs are threatened by a host of environmental problems, including deforestation, hunting for bushmeat, live capture for the exotic pet trade,[140] and climate change.[94] DELL Studio XPS 1340 CPU FAN
All species are listed by CITES on Appendix I, which prohibits trade of specimens or parts, except for scientific purposes.[1] As of 2005, the International Union for Conservation of Nature (IUCN) listed 16% of all lemur species as Critically Endangered, 23% as Endangered, 25% as Vulnerable, 28% as "Data Deficient", and only 8% as Least Concern.[133] Over the next five years, at least 28 species were newly identified, none of which have had their conservation status assessed.[42] DELL Studio XPS 1640 CPU FAN
Many are likely to be considered threatened since the new lemur species that have been described recently are typically confined to small regions.[141] Given the rate of continued habitat destruction, undiscovered species could go extinct before being identified.[59] Since the arrival of humans on the island approximately 2000 years ago, all endemic Malagasy vertebrates over 10 kg (22 lb) have disappeared,[34] including 17 species, 8 genera, and 3 families of lemurs.[33][36] DELL Studio XPS 1645 CPU FAN
The IUCN Species Survival Commission (IUCN/SSC), the International Primatological Society(IPS), and Conservation International (CI) have included as many as five lemurs in their biennial "Top 25 Most Endangered Primates". The 2008–2010 list includes the greater bamboo lemur, gray-headed lemur (Eulemur cinereiceps), blue-eyed black lemur (Eulemur flavifrons), northern sportive lemur (Lepilemur septentrionalis), and silky sifaka.[142] DELL Studio XPS 1647 CPU FAN
In 2012, an assessment by the Primate Specialist Group of the International Union for the Conservation of Nature (IUCN) concluded that 90% of the then 103 described species of lemur should be listed as Threatened on the IUCN Red List,[143] making lemurs the most endangered group of mammals.[144] The IUCN reiterated its concern in 2013, noting that 90% of all lemur species could be extinct within 20 to 25 years unless a $7 million USD 3-year conservation plan aimed at helping local communities can be implemented.[145][146] DELL Vostro 1000 Series CPU FAN

Madagascar is one of the poorest countries in the world,[147][148] with a high population growth rate of 2.5% per year and nearly 70% of the population living in poverty.[35][147] The country is also burdened with high levels of debt and limited resources.[148] These socioeconomic issues have complicated conservation efforts, even though the island of Madagascar has been recognized by IUCN/SSC as a critical primate region for over 20 years.[141] DELL Vostro 1014 Series CPU FAN
Due to its relatively small land area—587,045 km2 (226,659 sq mi)—compared to other high-priority biodiversity regions and its high levels of endemism, the country is considered one of the world's most important biodiversity hotspots, with lemur conservation being a high priority.[133][141] Despite the added emphasis for conservation, there is no indication that the extinctions that began with the arrival of humans have come to an end. DELL Vostro 1015 Series CPU FAN

The greatest concern facing lemur populations is habitat destruction and degradation.[35][1] Deforestation takes the form of local subsistence use, such as slash and burn agriculture (referred to as tavy in Malagasy), the creation of pasture for cattle through burning, and legal and illegal gathering of wood for firewoodor charcoal production; commercial mining; and the illegal logging of precious hardwoods for foreign markets.[35][140] DELL Vostro 1018 Series CPU FAN
After centuries of unsustainable use, as well as rapidly escalating forest destruction since 1950,[133] less than 60,000 km2 (23,000 sq mi) or 10% of Madagascar's land area remains forested. Only 17,000 km2 (6,600 sq mi) or 3% of the island's land area is protected and due to dire economic conditions and political instability, most of the protected areas are ineffectively managed and defended.[140][141] DELL Vostro 1088 Series CPU FAN
Some protected areas were set aside because they were naturally protected by their remote, isolated location, often on steep cliffs. Other areas, such as the dry forests and spiny forests of the west and south, receive little protection and are in serious danger of being destroyed.[35]

Some species may be in risk of extinction even without complete deforestation, such as ruffed lemurs, which are very sensitive to habitat disturbance.[59] DELL Vostro 1310 CPU FAN
If large fruit trees are removed, the forest may sustain fewer individuals of a species and their reproductive success may be affected for years.[94] Small populations may be able to persist in isolated forest fragments for 20 to 40 years due to long generation times, but in the long term, such populations may not be viable.[149] Small, isolated populations also risk extirpation by natural disasters and disease outbreaks (epizootics). DELL Vostro 1400 Series CPU FAN
Two diseases that are lethal to lemurs and could severely impact isolated lemur populations are toxoplasmosis, which is spread by feral cats, and the herpes simplex virus carried by humans.

Climate change and weather-related natural disasters also threaten lemur survival. For the last 1000 years, western and highland regions have been growing significantly drier, but in the past few decades, severe drought has become much more frequent. DELL Vostro 1510 CPU FAN
There are indications that deforestation and forest fragmentation are accelerating this gradual desiccation.[94] The effects of drought are even felt in the rainforests. As annual rainfall decreases, the larger trees that make up the high canopy suffer increased mortality, failure to fruit, and decreased production of new leaves, which folivorous lemurs prefer. Cyclones can defoliate an area, knock down canopy trees, and create landslides and flooding. DELL Vostro 1700 CPU FAN
This can leave lemur populations without fruit or leaves until the following spring, requiring them to subsist on crisis foods, such as epiphytes.[151]

Lemurs are hunted for food by the local Malagasy, either for local subsistence[4][140] or to supply a luxury meat market in the larger cities.[152] DELL Vostro 2510 CPU FAN
Most rural Malagasy do not understand what "endangered" means, nor do they know that hunting lemurs is illegal or that lemurs are found only in Madagascar.[153] Many Malagasy have taboo, or fady, about hunting and eating lemurs, but this does not prevent hunting in many regions.[11] Even though hunting has been a threat to lemur populations in the past, it has recently become a more serious threat as socioeconomic conditions deteriorate.[140] DELL Vostro 3300 CPU FAN
Economic hardships have caused people to move around the country in search of employment, leading local traditions to break down.[59][1][153] Drought and famine can also relax the fady that protect lemurs.[59] Larger species, such as sifakas and ruffed lemurs, are common targets, but smaller species are also hunted or accidentally caught in snares intended for larger prey.[4][1] Experienced, organized hunting parties using firearms, slings and blowguns can kill as many as eight to twenty lemurs in one trip. DELL Vostro 3350 CPU FAN
Organized hunting parties and lemur traps can be found in both non-protected areas and remote corners of protected areas.[59] National parks and other protected areas are not adequately protected by law enforcement agencies.[153] Often, there are too few park rangers to cover a large area, and sometimes terrain within the park is too rugged to check regularly.[154]

Although not as significant as deforestation and hunting, some lemurs, such as crowned lemurs and other species that have successfully been kept in captivity, are occasionally kept as exotic pets by Malagasy people.[50][133] DELL Vostro 3400 CPU FAN
Bamboo lemurs are also kept as pets,[133] although they only survive for up to two months.[155]Live capture for the exotic pet trade in wealthier countries is not normally considered a threat due to strict regulations controlling their export.

Lemurs have drawn much attention to Madagascar and its endangered species. In this capacity, they act as flagship species,[59][133] the most notable of which is the ring-tailed lemur, which is considered an icon of the country.[57] DELL Vostro 3450 CPU FAN
The presence of lemurs in national parks helps drive ecotourism,[133] which especially helps local communities living in the vicinity of the national parks, since it offers employment opportunities and the community receives half of the park entrance fees. In the case of Ranomafana National Park, job opportunities and other revenue from long-term research can rival that of ecotourism.[156] DELL Vostro 3500 CPU FAN

Starting in 1927, the Malagasy government has declared all lemurs as "protected"[68] by establishing protected areas that are now classified under three categories: National Parks (Parcs Nationaux), Strict Nature R

eserves (Réserves Naturelles Intégrales), and Special Reserves (Réserves Spéciales). There are currently 18 national parks, 5 strict nature reserves, and 22 special reserves, as well as several other small private reserves, such as Berenty Reserve and Sainte Luce Private Reserve, both near Fort Dauphin.[133] DELL Vostro 3700 CPU FAN
All protected areas, excluding the private reserves, comprise approximately 3% of the land surface of Madagascar and are managed by Madagascar National Parks, formerly known as l'Association Nationale pour la Gestion des Aires Protégées (ANGAP), as well as other non-governmental organizations (NGOs), including Conservation International (CI), the Wildlife Conservation Society (WCS), and the World Wide Fund for Nature (WWF).[133][141] DELL Vostro 3700 Series CPU FAN
Most lemur species are covered by this network of protected areas, and a few species can be found in multiple parks or reserves.[141]

Conservation is also facilitated by the Madagascar Fauna Group (MFG), an association of nearly 40 zoos and related organizations, including the Duke Lemur Center, the Durrell Wildlife Conservation Trust, and the Saint Louis Zoological Park. DELL Vostro 3750 CPU FAN
This international NGO supports Madagascar's Parc Ivoloina, helps protectBetampona Reserve and other protected areas, and promotes field research, breeding programs, conservation planning, and education in zoos.[157] One of their major projects involved the release of captive black-and-white ruffed lemurs, designed to help restock the dwindling population within Betampona Reserve.

Habitat corridors are needed for linking these protected areas so that small populations are not isolated.[141] DELL Vostro A840 CPU FAN
InSeptember 2003 in Durban, South Africa, Madagascar's former president Marc Ravalomanana promised to triple the size of the island's protected areas in five years.[140] This became known as the "Durban Vision".[133] In June 2007, the World Heritage Committee included a sizable portion of Madagascar's eastern rainforests as a new UNESCO World Heritage Site.[30]

Debt relief may help Madagascar protect its biodiversity.[148] DELL Vostro A860 CPU FAN
With the political crisis in 2009, illegal logging has proliferated and now threatens rainforests in the northeast, including its lemur inhabitants and the ecotourism that the local communities rely upon.[147]

Captive lemur populations are maintained outside of Madagascar in many zoos, although the diversity of species is limited. Sikafas, for instance, do not survive well in captivity, so few facilities have them.[11][60] DELL XPS L501X CPU FAN
The largest captive lemur population can be found at the Duke Lemur Center (DLC), whose mission includes non-invasive research, conservation (e.g.captive breeding), and public education.[133] Another large lemur colony the Myakka City Lemur Reserve run by the Lemur Conservation Foundation (LCF), which also hosts lemur research.

In Malagasy culture lemurs, and animals in general, have souls (ambiroa) which can get revenge if mocked while alive or if killed in a cruel fashion. DELL XPS L502X CPU FAN
Because of this, lemurs, like many other elements of daily life, have been a source of taboos, known locally as fady, which can be based around stories with four basic principles. A village or region may believe that a certain type of lemur may be the ancestor of the clan. They may also believe that a lemur's spirit may get revenge. Alternatively, the animal may appear as a benefactor. Lemurs are also thought to impart their qualities, good or bad, onto human babies.[160] DELL XPS M1210 CPU FAN
In general, fady extend beyond a sense of the forbidden, but can include events that bring bad luck.

One example of lemur fady told around 1970 comes from Ambatofinandrahana in the Fianarantsoa Province. According to the account, a man brought a lemur home in a trap, but alive. His children wanted to keep the lemur as a pet, but when the father told them it was not a domestic animal, the children asked to kill it. DELL XPS M1330 CPU FAN
After the children tortured the lemur, it eventually died and was eaten. A short time later, all the children died of illness. As a result, the father declared that anyone who tortures lemurs for fun shall "be destroyed and have no descendants."[160]

Fady can not only help protect lemurs and their forests under stable socioeconomic situations, but they can also lead to discrimination and persecution if a lemur is known to bring bad fortune, for instance, if it walks through town.[59][160] DELL XPS M140 CPU FAN
In other ways, fady does not protect all lemurs equally. For example, although the hunting and eating of certain species may be taboo, other species may not share that same protection and are therefore targeted instead.[11][160] Fady can vary from village to village within the same region.[68] If people move to a new village or region, their fady may not apply to the lemur species that are locally present, making them available for consumption. DELL XPS M1530 CPU FAN
Fady restrictions on lemur meat can be relaxed in times of famine and drought.[59]

The aye-aye is almost universally viewed unfavorably across Madagascar,[79] though the tales vary from village to village and region to region. If people see an aye-aye, they may kill it and hang the corpse on a pole near a road outside of town (so others can carry the bad fortunes away) or burn their village and move.[51][68] DELL XPS M170 CPU FAN

The superstitions behind aye-aye fady include beliefs that they kill and eat chickens or people, that they kill people in their sleep by cutting their aortic vein,[59] that they embody ancestral spirits,[68] or that they warn of illness, death, or bad luck in the family.[50][51] As of 1970, the people of the Marolambo District in the Toamasina Province feared the aye-aye because they believed it had supernatural powers. Because of this, no one was allowed to mock, kill, or eat one.[160] DELL Inspiron 1501 Series CPU FAN

There are also widespread fady about indri and sifakas. They are often protected from hunting and consumption because of their resemblance to humans and their ancestors, mostly due to their large size and upright or orthograde posture. The resemblance is even stronger for indri, which lack the long tail of most living lemurs.[60][80] Known locally as babakoto ("Ancestor of Man"), the indri is sometimes seen as the progenitor of the family or clan. DELL Inspiron 1520 Series CPU FAN
are also stories of an indri that helped a human down from a tree, so they are seen as benefactors.[160] Other lemur fady include the belief that a wife will have ugly children if her husband kills a woolly lemur, or that if a pregnant woman eats a dwarf lemur, her baby will get its beautiful, round eyes.[160]

Lemurs have also become popular in Western culture in recent years. DELL Inspiron 1521 Series CPU FAN
The original 2005 animated film Madagascar was seen by an estimated 100 million people in theaters and 200–300 million people on DVD worldwide.[58] Prior to this movie, Zoboomafoo, a Public Broadcasting Service (PBS) children's television series from 1999 to 2001,[161] helped to popularize sifakas by featuring a live Coquerel's sifaka from the Duke Lemur Center as well as a puppet.[162] DELL Inspiron 1525 Series CPU FAN
A twenty-episode series called Lemur Kingdom (in the United States) or Lemur Street (in the United Kingdom and Canada) aired in 2008 on Animal Planet. It combined the typical animaldocumentary with dramatic narration to tell the story of two groups of ring-tailed lemurs at Berenty Private Reserve.The movie Fierce Creatures includes a lemur (as well as the main cast) on its poster. DELL Inspiron 1526 Series CPU FAN,DELL Inspiron 1545 Series CPU FAN,DELL Inspiron 1546 Series CPU FAN

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