Geography of Africa in the lake of organisms of a decidedly marine type. They include jellyfish, molluscs, prawns, crabs, etc. With the exception of Madagascar, the African islands are small. Madagascar, with an area of , is, after Greenland, New Guinea and Borneo, the fourth largest island on the Earth. It lies in the Indian Ocean, off the S.E. coast of the continent, from which it is separated by the deep Mozambique channel, wide at its narrowest point. Madagascar in its general structure, as in flora and fauna, forms a connecting link between Africa and southern Asia. East of Madagascar are the small
Australia (continent) collision also pushed up the islands of Wallacea, which served as island 'stepping-stones' that allowed plants from Southeast Asia's rainforests to colonise New Guinea, and some plants from Australia–New Guinea to move into Southeast Asia. The ocean straits between the islands were narrow enough to allow plant dispersal, but served as an effective barrier to exchange of land mammals between Australia–New Guinea and Asia. Prominent features of the Australian flora are adaptations to aridity and fire which include scleromorphy and serotiny. These adaptations are common in species from the large and well-known families Proteaceae ("Banksia"), Myrtaceae ("Eucalyptus" – gum trees),