Proteas are assigned their own family, the Proteacea, based on their specialized flower structures. The name comes from the
Greek god Proteus who brought fire to humans—perhaps because the flowers resemble flames (although there is some debate
on this point). They were first collected in South Africa in 1605 by a Dutch botanist. Modern scientific names of the then
known species were given by Linnaeus (the 'father' of taxonomy) in 1750. Today, they"re given various common names
such as sugarbush, or shaving brush bush.
The protea family includes about 1,400 species, almost entirely restricted to the southern hemisphere. Some 360 species in 14
genera are found within southern-central Africa, but most are restricted to the Cape region of South Africa.
Proteas employ a variety of pollination strategies, 'hedging their bets' to maximize the chances of pollination,
necessary to produce seed and so reproduce. Some species are pollinated by flower-visiting rodents and a number by nectar-feeding
birds. Sugarbirds and sunbirds are the most important. Beetles also visit the flowers, such as the protea beetle Trichostetha
fascicularis—as many as 2,000 insects have been found in a single flower head.
Despite the large flowers, some proteas do not produce many seeds. Usually less than a third of the flowers actually set seed.
In species where male and female flowers occur on separate plants (dioecious), the fertility is much higher.
Fire is an important shaper of the African landscape, and proteas have evolved a number of adaptations to survive the frequent
scouring. Some simply avoid areas where fire is prevalent and grow in rocky crags or creep through cracks or depressions in the
ground. These are not truly resistant. Other species produce a thick bark which insulates the live cells and leaf buds in the
stem. The fire does not penetrate the bark, and the plant regrows lost leaves. Another approach is to hide underground. The
plant"s above-ground parts are burned away, but it has a tough root stock that quickly sprouts new stems after the fire
passes. A number of species will not release seeds until exposed to fire, and hence depend on fire to reproduce.
Although proteas are well-adapted to their natural habitat, anumber of species are considered at risk of extinction and four
species are believed to be extinct. In South Africa, a third of the species are considered threatened or at risk. The main problems
are loss of habitat due to agriculture and non-native forestry, and over-collection. Disease is responsible for significant die-offs,
especially when exotic pathogens (bacteria, fungi, etc.) are inadvertently tracked in by people.
While the future of cultivated proteas generally seems secure, it is evident that the group is under pressure. Conservationists
will be working hard to maintain many of the wild species.
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