Tuesday, October 15, 2013
Each utilizes either different species of bamboo
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 Reserves (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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