Cycads typically have a stout and woody (ligneous) trunk with a crown of large, hard and stiff, evergreen leaves. source
Cycads typically have a stout and woody (ligneous) trunk with a crown of large, hard and stiff, evergreen leaves.
Cycads vary in size from having trunks only a few centimeters to several meters tall. source
Cycads vary in size from having trunks only a few centimeters to several meters tall.
Cycads typically grow very slowly and live very long, with some specimens known to be as much as 1,000 years old. source
Cycads typically grow very slowly and live very long, with some specimens known to be as much as 1,000 years old.
The living cycads are found across much of the subtropical and tropical parts of the world. source
The living cycads are found across much of the subtropical and tropical parts of the world.
The three extant families of cycads are Cycadaceae, Stangeriaceae, and Zamiaceae. source
The three extant families of cycads are Cycadaceae, Stangeriaceae, and Zamiaceae.
Cycads have changed little since the Jurassic, compared to some major evolutionary changes in other plant divisions. source
Cycads have changed little since the Jurassic, compared to some major evolutionary changes in other plant divisions.
Cycads are gymnosperms (naked seeded), meaning their unfertilized seeds are open to the air to be directly fertilized by pollination. source
Cycads are gymnosperms (naked seeded), meaning their unfertilized seeds are open to the air to be directly fertilized by pollination.
Cycads have very specialized pollinators, usually a specific species of beetle. source
Cycads have very specialized pollinators, usually a specific species of beetle.
Cycads have been reported to fix nitrogen in association with various cyanobacteria living in the roots (the "coralloid" roots). source
Cycads have been reported to fix nitrogen in association with various cyanobacteria living in the roots (the "coralloid" roots).
Photosynthetic bacteria produce a neurotoxin called BMAA that is found in the seeds of cycads. source
Photosynthetic bacteria produce a neurotoxin called BMAA that is found in the seeds of cycads.
The probable former range of cycads can be inferred from their global distribution. source
The probable former range of cycads can be inferred from their global distribution.
The cycad fossil record dates to the early Permian, 280 million years ago (mya). source
The cycad fossil record dates to the early Permian, 280 million years ago (mya).
