Thursday, March 1, 2012

What Do Cycads and Ginkgos have in Common?

Answer: They both have motile sperm.

They're both gymnosperms, plants bearing "naked seeds," i.e. their unfertilized seeds are unenclosed, open to the air for direct fertilization by pollination.

Additionally, they are both fairly ancient species — cycads have been around since at least the early Permian, roughly 280 million years ago (though most extant cycad species have evolved in only the last 12 million years) — and the gingkos nearly as long, 270 million years.

And, you can find both species here on Shikoku.

 *Illustration above from Dokobara by Kumiko Takeuchi 2008               

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