10.27.2010

Cycads

Living fossils from the Jurassic age these Sago Palms (Cycas revoluta) aren't really palms at all, but Cycads - a type of seed plant that could be the evolutionary link between primitive ferns and more evolved flowers.  (I love organisms that defy classification - fungi in their own kingdom, chloroplastic sea slugs that are part animal/part plant)  I got one at the farmers market for my grandma so she could see firsthand what the vegetation in South Carolina is like.

However, my brother with his always-questioning nature didn't believe me that they're not palms and reproduce more like conifers.  So @Stephen_Job here you go:  Cycads are a division of their own (Cycadophyta) within the seed producers (Spermatophytes) but while they share characteristics and are often mistaken for both the seedless vascular plants such as ferns (Pteridophyte), and the more evolved flowering plants such as palms (Palmaceae) they produce neither flowers nor seeds and represent an interesting intermediate between both plants.  Instead of requiring two separate generations and organisms (plant and spore) in order to reproduce like ferns, cycads produce modified leaves (sporophytes) which develop either cones or seed-like megaspores at the base and require pollination just like dioecious flowering plants.  But for some reason Cycads stayed put at that point in their evolution while the conifers and flowering plants passed them by allowing us a little window into the forests of the Jurassic period!

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