Madagascar has been an isolated island for about 70 million years, breaking away from Africa around 165 million years ago, then from India nearly 100 million years later. This isolation led to the development of a unique endemicfauna.
Before humans arrived about 2,000 years ago, there were many large and unusual animals living there, descended from species that were originally present when Madagascar became an island, or from species that later crossed the sea to Madagascar. Ecological niches were often filled by animals with quite different histories from those on the African mainland, often leading to convergent evolution. A large proportion of these endemic Malagasy animals have died out since the arrival of humans, most particularly the megafauna.
Despite this, and massive deforestation, Madagascar is still home to an incredible array of wildlife, the vast majority of which is unique in the world.[1] Madagascar is a primary spot for ecotourism,[2] with more than fifty national parks and other protected reserves.
There are believed to have been only four colonization events of terrestrial mammals from mainland Africa. They brought to Madagascar the ancestors of its tenrecs, lemurs, carnivorans and nesomyine rodents. The other mammalian colonizations were those of the amphibious hippopotamuses (now extinct) and bats.
The lemurs are the best known of Madagascar's mammals.[3] They can be found only on Madagascar. In the absence of monkeys and other competitors, these primates have adapted to a wide range of habitats and diversified into numerous species. The tenrecs are another group of mammals characteristic of Madagascar. Most of the world's species of these small to medium-sized insectivores are found on the island. Rodents are poorly represented on the island with only a handful of native species, all belonging to the subfamily Nesomyinae. They include the large, endangered Malagasy giant rat. Due to their ability to fly, a greater variety of bats have reached the island. However, only about a third of these are endemic, a lower proportion than in other groups of land mammals. There are eight members of the Carnivora on the island, all now classified in the endemic family Eupleridae. The cat-like fossa is the largest of these.
Malagasy living mammals
Lemurs: As of 2008, there are officially 99 species and subspecies of lemur, 39 of which have been described by zoologists between 2000 and 2008.[4] Of the 51 species that were evaluated by the IUCN that year, 43 were categorized as threatened to some degree, with six species being classified as "Critically Endangered", the designation of highest risk.[5] The evaluations became considerably more pessimistic in 2012.[6]
Eupleridae: Primary among these malagasy carnivores is the fossa (Cryptoprocta ferox), an animal similar in appearance to a feline. Other Malagasy carnivores include the fanaloka (Fossa fossana), which, despite its scientific name, should not be confused with the fossa. Nor should it be confused with the very similarly named falanouc (Eupleres goudotii), also known as the Malagasy small-toothed civet. Five species of mongoose are also found in Madagascar, as is the small Indian civet, one of the carnivores believed to have been introduced to the island.
Rodents: About 30 species of indigenous rodent are known from Madagascar, three of which are now extinct. They are all members of the muroid subfamily Nesomyinae. These have also radiated into various niches, with vole-like forms, arboreal mice, fossorial varieties, and rabbit-like forms.
Bats: Approximately 69 species of bat are known from Madagascar, more than half of which are endemic to the island (see List of bats of Madagascar).
Malagasy extinct mammals
Plesiorycteropus (P. germainepetterae, P. madagascariensis): One or two species of mysterious aardvark-like tenrec relatives that may have gone extinct about 1000 years ago.
Giant fossa (Cryptoprocta spelea): The fossil record of Madagascar has yielded the remains of a recently extinct fossa which was about a quarter larger than the living species,[8] making it close to the size of an ocelot. This species was believed to have preyed upon the larger lemurs that inhabited Madagascar until the island was settled by man.
Malagasy hippopotamuses: There are thought to have been three species of dwarf or pygmy hippopotamus in Madagascar,[9] the last of which died out no earlier than 1,000 years ago, probably as a result of human settlement of the island.
About 280 species of bird have been recorded on Madagascar and about 200 of these breed. Although these are relatively low numbers for a large tropical island, there is a high degree of endemism. Over 100 bird species are endemic and 49 of these are restricted-range endemics with a range of less than 50,000 km2. There are five bird families unique to Madagascar or shared only with the Comoro Islands: the mesites, the ground-rollers, the cuckoo-roller, the asities and the vangas. In addition, recent studies suggest that several songbirds should be grouped together in a new endemic family: the Malagasy warblers.
Elephant birds (e.g. Aepyornis maximus) were flightless ratites up to over three metres tall and half a tonne in weight. Genetic studies have revealed that their closest living relatives are the kiwi of New Zealand, rather than the nearby ostriches of Africa; i.e., their presence on the island appears to be due to long-range dispersal rather than vicariance.[10] They are thought to have become extinct within the last millennium, as a result of human activity. Other endemic birds that have disappeared since human settlement of the island include the Malagasy lapwing[11] and Malagasy shelduck.[12]
There are more than 290 amphibian species in Madagascar with new species being found regularly.[16] Nearly all of these are endemic and the majority are restricted to primary forest. Examples of well-known amphibian species found in Madagascar include tomato frog and golden mantella frog.
The geographic history of Madagascar (long isolated, but part of Gondwana) has resulted in unusual biogeographic patterns, comparable to those seen in other animal and plant groups of the island. For example, the closest relatives of the Madagascar rainbowfish are the "true" rainbowfish of New Guinea and Australia,[22] while the killifish Pachypanchax and the cichlids Paretroplus have their closest relatives in South Asia.[23]
Madagascar is home to huge variety of insects, the majority of which are endemic. Thousands of species are present in some groups such as the beetles and moths. There are approximately 100,000 species of insects and counting in Madagascar. Distinctive species include the long-necked giraffe weevil, the huge comet moth and the butterfly-like Madagascan sunset moth. About 80 species of stick insect occur; the Achrioptera species are large and colourful while others are small and very well-camouflaged. Many of the island's praying mantises are also well-camouflaged, mimicking dead leaves or bark. There are over 100 cockroaches, including the large hissing cockroaches.
The mosquitoes of Madagascar include 235 species, among which 138 (59%) are endemic and 64 (27%) have a known medical or veterinary interest because they can transmit diseases.[27]
Madagascar is home to the smallest bee in the World, Liotrigona bitika (Brooks & Michener 1988) with a body length of less than 2 mm, and to several other species of Meliponini.[30]
Spiders
Darwin's bark spider was discovered in 2009. It is famous for making the strongest and largest spider webs (ranging from 900 – 28000 square centimetres). The silk produced by this spider is twice as strong as other common spider silk.[32]
The seas around Madagascar host a high diversity of wildlife, including invertebrates.[36] There is a still a large area of mangrove swamp around the coast, particularly in the west, and there are extensive coral reefs around the island. Thousands of fish species occur, including the rare coelacanth. Four species of sea turtle breed on the beaches, but many are taken for food by local people. For whales, humpback whales breed off the south-western coasts such as at Île Sainte-Marie, Omura's whales notably around Nosy Be,[37]pygmy blue whales on the Madagascar Plateau,[38] and southern right whales slowly increasing along Malagasy coasts.[39]
Most of Madagascar's habitats are in danger; they are being threatened by today's demands and growing needs. Environmental damage has been especially severe for humid forests.[45]Fauna and Flora International, abbreviated as FFI is one of the organizations that supports Madagascar's habitats.[46]
In popular culture
As a part of conservation efforts, the Wildlife Conservation Society has recently opened a Madagascar! exhibit at the Bronx Zoo.
The 2005 animated film Madagascar featured a number of animals of Madagascar as cartoon characters.
^Okajima, Y.; Kumazawa, Y. (15 July 2009). "Mitogenomic perspectives into iguanid phylogeny and biogeography: Gondwanan vicariance for the origin of Madagascan oplurines". Gene. 441 (1–2). Elsevier: 28–35. doi:10.1016/j.gene.2008.06.011. PMID18598742.
^Ng, and Sparks (2005). Revision of the endemic Malagasy catfish family Anchariidae (Teleostei: Siluriformes), with descriptions of a new genus and three new species. Ichthyol. Explor. Freshwaters 16(4): 303–323.
^Sparks; and Smith (2004). Phylogeny and biogeography of the Malagasy and Australasian rainbowfishes (Teleostei: Melanotaenioidei): Gondwanan vicariance and evolution in freshwater. Molecular Phylogenetics and Evolution 33(3): 719–734
^Sparks; and Smith (2004). 'Phylogeny and biogeography of the Malagasy and Australasian rainbowfishes (Teleostei: Melanotaenioidei): Gondwanan vicariance and evolution in freshwater. Molecular Phylogenetics and Evolution 33(3): 719–734.
^Sparks (2004). Molecular phylogeny and biogeography of the Malagasy and South Asian cichlids (Teleostei: Perciformes: Cichlidae). Molecular Phylogenetics and Evolution 30(3): 599–614.
^Razafindrakoto, M., Csuzdi, Cs. & Blanchart, E. 2011. New and little known giant earthworms from Madagascar (Oligochaeta: Kynotidae). African Invertebrates52 (2): 285–294.[1]Archived 21 October 2011 at the Wayback Machine
^ abJones; Andriahajaina; Hockley; Crandall; and Roavohangimalala (2007). The ecology and conservation status of Madagascar's endemic freshwater crayfish (Parastacidae; Astacoides). Freshwater Biology 52(9): 1820–1833.
^Cumberlidge (2008). Insular species of Afrotropical freshwater crabs (Crustacea: Decapoda: Brachyura: Potamonautidae and Potamidae) with special reference to Madagascar and the Seychelles. Contributions to Zoology 77(2): 71–81.
^Cumberlidge, Klaus, Meyer & Koppin (2015). New collections of freshwater crabs from northern Madagascar, with the description of a new species of Foza Reed & Cumberlidge, 2006 (Brachyura, Potamonautidae), and comments on their conservation status. European Journal of Taxonomy 109: 1–15.
^Jefferson, Thomas; Marc A. Webber & Robert L. Pitman (2015). Marine Mammals of the World: A Comprehensive Guide to their Identification. London: Academic.
^Bauchot, M-L. & G. Bianchi 1984. Guide de poisons commerciaux de Madagascar (espèces marines et d'eaux saumâtres). Rome : FAO.
^Pellegrin, M. Jacques 1933. Les poissons des eaux douces de Madagascar et des iles voisines (Comores, Seychelles, Mascareignes). Tananarive : G. Pitot et Cie.
^Richmond, M.D. 2002. A field guide to the seashores of Eastern Africa and the Western Indian Ocean islands (2nd ed). Milan: SIDA/SAREC – University of Dar es Salaam.