Geography of New Caledonia - Biological Isolation

Biological Isolation

See also: Biodiversity of New Caledonia and Endemic Birds of New Caledonia

Given its geographical isolation since the end of the Cretaceous, New Caledonia is a refugium, in effect a biological "Noah's Ark", an island home to both unique living plants and animals and also to its own special fossil endowment. Birds such as the crested and almost flightless Kagu (French, Cagou) Rhynochetos jubatus, whose closest relative may be the distantly related Sunbittern of South America, and plants such as Amborella trichopoda, the only known member of the most basal living branch of flowering plants, make this island a treasure trove and a critical concern for biologists and conservationists. The island was home to horned fossil turtles (Meiolania mackayi) and terrestrial fossil crocodiles (Mekosuchus inexpectatus) which went extinct shortly after human arrival. There are no native amphibians, with geckos holding many of their niches. The Crested Gecko (Rhacodactylus ciliatus), thought to have gone extinct, was rediscovered in 1994. At 14 inches, Leach's Giant Gecko (Rhacodactylus leachianus), the world's largest and a predator of smaller lizards is another native. The only native mammals are four species of bat including the endemic New Caledonia Flying Fox.

New Caledonia is home to 13 of the 19 extant species of evergreens in the genus Araucaria. The island has been called "a kind of 'Jurassic Park'" because of the archaic characteristics of its highly endemic vegetation. In addition to the basal angiosperm plant genus Amborella, for example, the island is home to more gymnosperm species than any other tropic landmass, with 43 of its 44 conifer species being unique to the island, which is also home to the world's only known parasitic gymnosperm, the rootless conifer Parasitaxus usta.

Given their prehistoric appearance, the dry forests of western New Caledonia were chosen as the location for filming the first episode of the BBC miniseries Walking with Dinosaurs, which was set in the Arizona of the late Triassic.