The Littlest Kingdom
Nestled in the ramparts of the Cape Fold Belt Mountains at the tip of Africa, lies a little relic of Gondwana: the Cape Floristic Kingdom. Only 90 000km2 in area, it contains over one third of the 24 000 species on the subcontinent. Over 60 per cent of these plant species are found nowhere else. Most floriferous of the plant communities making up the littlest kingdom is Fynbos. The three distinctive plant families of Fynbos, the Proteas, Heaths (Ericaceae) and Cape Reeds (Restionaceae) have erroneously become synonymous with the Cape Floral Kingdom. Although Fynbos dominates the plant species tally and contains seven endemic families, it is largely confined to the mountains and coastal sands. Several other plant communities containing very few Fynbos species are also widespread: Renosterveld once supported the roving herds of quagga, bontebok, bloubok and hartebeest before being converted, first to grazing and then to wheat. Succulent Karoo is renowned for its proliferation of vygie bushes (Mesembryanthemaceae) and spring daisy displays, and Thicket which is characterised by spiny bushes with bird-dispersed seeds. And lastly, Afromontane Forest, which actually does contain trees.
The Fynbos of today has not been around for long: 10 million years ago the region was dominated by Gymnosperm and palm forests with a Fynbos understory - except that the heaths were largely absent. What event decimated the forests is unknown: the period following did see the formation of ice on Antarctica, the start of the cold Benguella current, the collision of Africa with Europe and the resulting upthrust to form the great escarpment. By the time the glaciers marched over the northern continents, Fynbos alone dominated the ramparts: a vestige of a once quite different Gondwana flora which certainly reached as far as Madagascar until that fateful, unknown event.
The Proteaceae parallel the distribution of species richness in other temperate plant families in the Cape Flora, all the way along the escarpment to the Great African Rift Valley. The distribution and habitat data collected by the Proteaceae Atlas Project will provide an essential baseline with which to select taxa for studying the factors which either accelerated speciation or reduced extinction in the Cape Floral Region. The littlest kingdom is a potential pandoras box to existing theories of plant community ecology, biogegraphy and evolution. The mapping of species distributions is the first step to understanding why the littlest kingdom is so rich in species.