Palaeotropics

The Paleotropical Kingdom (Paleotropis) is a floristic kingdom comprising tropical areas of Africa, Asia and Oceania (excluding Australia and New Zealand), as proposed by Ronald Good and Armen Takhtajan. Part of its flora, inherited from the ancient supercontinent of Gondwana or exchanged later (e.g. Piperaceae with pantropical distribution and but few warm temperate representatives), is shared with the Neotropical Kingdom, comprising tropical areas of Central and South America. Moreover, the Paleotropical flora influenced the tropical flora of the Australian Kingdom. The Paleotropical Kingdom is subdivided into five floristic subkingdoms according to Takhtajan (or three, according to Good) and about 13 floristic regions. In this article the floristic subkingdoms and regions are given as delineated by Takhtajan.

A distinct community of vascular plants evolved millions of years ago, and are now found on several separate areas. Millions of years ago, the warmer and wetter areas supported a tropical adapted flora, including forests of podocarps and southern beech. They were a type of flora characteristic of parts of Gondwana but were present in equivalent ecological areas.

Over millions of years, these type of vegetation present, covered much of the tropics of Earth. Many species are today relicts of a type of vegetation disappeared, which originally covered much of the mainland of Africa, Madagascar, India, South America, Antarctica, Australia, North America, Europe, and other lands when their climate were more humid and warm. Although warm Cloud forests disappeared during the glaciations, they re-colonized large areas every time the weather was favorable again. Most of the Cloud forests are believed to have retroced and advanced during successive geological eras, and their species adapted to warm and wet gradually retreated and advanced, replaced by more cold-tolerant or drought-tolerant sclerophyll plant communities. Many of the then existing species became extinct because they could not cross the barriers posed by new oceans, mountains and deserts, but others found refuge as species relict in coastal areas and Islands.

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