Fauna of Madagascar

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A good example of malagasy convergent evolution is the fossa, a malagasy carnivore that has evolved in appearance and behaviour to be so like a large cat that it was originally classified in felidae, when it is in fact more closely related to the mongoose
A good example of malagasy convergent evolution is the fossa, a malagasy carnivore that has evolved in appearance and behaviour to be so like a large cat that it was originally classified in felidae, when it is in fact more closely related to the mongoose

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.

Prior to the arrival of humans 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 five colonization events of terrestrial mammals from mainland Africa. They are the tenrecs, the lemurs, the Malagasy carnivorans, the Nesomyinae, and the now-extinct bibymalagasians. The other mammalian colonizations are the amphibious hippopotamuses (now extinct) and bats.

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[edit] Malagasy fauna (living)

Lemurs: There are approximately 75 species of lemur, more than 25 of which have been described by zoologists in the last decade alone.[3] They are almost all classified as rare, vulnerable, or endangered.[4]

Eupleridae: Primary among these malagasy carnivores is the fossa (Cryptoprocta ferox), a type of civet despite its feline appearance. 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, the only carnivore believed to have been introduced to the island.

Tenrecs: Three species of tenrec (the otter shrews) are found on the African mainland. The majority of tenrecs, around 30 species, are found in Madagascar. They have radiated into many different niches. For example web-footed tenrecs (Limnogale mergulus) resemble river otters in appearance and behaviour. The lesser hedgehog tenrec (Echinops telfairi) resembles its namesake the hedgehog.

Rodents: Fourteen species of rodent are found on Madagascar. 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 30 species of bat are known from Madagascar, more than half of which are endemic to the island.

Reptiles: Madagascar is a stronghold for a wide diversity of endemic species of Chameleons and is considered the radiation point for day geckos.

Birds: see: Endemic birds of Madagascar and western Indian Ocean islands

Beetles: Various species of beetles. For example various tiger beetles (Cicindelidae): 109 species from genus Pogonostoma[5], 65 species from genus Physodeutera[6].

[edit] Malagasy fauna (extinct)

Giant lemurs: There are at least 17 species of lemur that have become extinct since man arrived on Madagascar, all of which were larger than the current lemur species. They include the giant Aye-aye, three to five times as heavy as the extant species. The Megaladapis, of which there were three species, could reach the size of orangutans. The sloth lemurs, which show remarkable evolutionary convergence with the South American sloths, with chimpanzee-sized Palaeopropithecus being very similar in body form to South American tree sloths. The sloth lemur Archaeoindris could reach a size of over 200kg,[7] more than a silverback gorilla.

Giant fossa: (Cryptoprocta spelea). The fossil record of Madagascar has yielded the remains of a giant, 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 different species of dwarf or pygmy hippo 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.

Elephant birds: (Aepyornis maximus). These enormous birds were over 3 metres tall and half a tonne in weight. They are thought to have become extinct within the last millennium, as a result of human activity, just like the dodo on the neighbouring island of Mauritius.

[edit] References

  1. ^ The Natural History of Madagascar, 2003
  2. ^ Madagascar Wildlife: A Visitor's Guide, 2nd ed., 2001
  3. ^ Lemurs of Madagascar (Conservation International Tropical Field Guide Series), 2006
  4. ^ Lemurs of Madagascar and the Comoros: The IUCN Red Data Book, 1990
  5. ^ Moravec Jiří, 2007: A monograph of the genus Pogonostoma. Tiger beetles of Madagascar, volume 1. 30 colour plates, 499 pp. (in English). ISBN 978-80-86447-13-1.
  6. ^ Moravec Jiří, 2002: A monograph of the genus Physodeutera. Tiger beetles of Madagascar, volume 2. 21 colour plates, 290 pp. (in English).
  7. ^ William L. Jungers, Laurie R. Godfrey, Elwyn L. Simons, and Prithijit S. Chatrath (1997 October 28). "Phalangeal curvature and positional behavior in extinct sloth lemurs (Primates, Palaeopropithecidae)". PNAS Proceedings of the National Academy of Sciences of the United States of America 94(22): 11998–12001. 
  8. ^ Goodman S. M., Rasoloarison R. M. and Ganzhorn J. U. (2004). On the specific identification of subfossil Cryptoprocta (Mammalia, Carnivora) from Madagascar. Zoosystema, 26 (1): 129-143. [available at http://www.mnhn.fr/museum/front/medias/publication/1334_z04n1a9.pdf]
  9. ^ Mammals of Madagascar by Nick Garbutt, 1999

[edit] See also

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