Cycads are dioecious, with separate male and female individuals. Large seeds with a fleshy coating and a hard centre are produced on the leaves. These are dispersed to nearby soil by birds, rodents and fruit bats, where they must germinate quickly to survive. If conditions are not suitable for germination, the seeds cannot lie dormant, and so will perish. Cycads are long-lived, slow-growing, and have a low reproductive rate. Their roots contain cyanobacteria that exist in a symbiotic relationship with the plant, and provide it with further nutrients by converting (fixing) atmospheric nitrogen into a usable form. The roots are also retractable for protection against drought and fire (2).
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