Field of Science

Cycad "flowering"

A check through the glasshouse found a number of our small cycads coning, mostly species of Zamia.  Here's a small specimen of Z. pumila showing the full display of seed cones at the time of pollination.  Not too much to see, but enough.  Note that near the top of the cone, the cone scales, aka megasporophylls, have separated a bit leaving a narrow zig-zaggy opening around the top of the cone.  Similar openings are found further down the cone too.  Cycads are very ancient seed plants, more ferny than other gymnosperms, and while ancient, they turn out to be insect pollinated.  Small beetles carry pollen from other plants bearing pollen cones to plants bearing seed cones where they carry pollen inside the cone where it makes contact with pollen drops and gets pulled inside the ovules (aka megasporangia, aka immature seeds).  After this pollination period, the cone closes until the seeds are mature and ready to disperse.  Pretty exciting, huh! 

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