Cycads
Cycads are known as ‘living fossils’ because they have
remained unchanged for millions of years. Study of the fossil record
reveals that these plants flourished some 280-135 million years
ago. They are scientifically important because they may represent
a link in the evolution from ferns to flowering plants. They have
been in decline perhaps ever since the flowering plants became dominant,
some 100 million years ago. Most species are now rare.
Cycads vary greatly in shape and size and grow in various climatic
zones from rainforest to semi-desert. They are all rather slow-growing
and, like conifers, bear their reproductive organs in cones. Male
and female cones are borne on separate plants. Half of the cycad
species in the Palm House are threatened in the wild.
Although all parts of cycads are toxic, they can provide a food
source for some communities, particularly in times of famine. The
toxins are removed by careful boiling and washing before use.
About cycads
cycads
at Kew
cycad
pollination
Plant
profiles
Dioon
spinulosum
Encephalartos
altensteinii
Encephalartos
woodii
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