Field of Science

Cycads aren't living fossils?

Well, shucks! Don’t you just hate it when science knocks a hole in one of your more romantic notions about things? Cycads are such fun organisms, so cool looking, and studied by such interesting people, with one rather short exception. The romantic notion the Phactor has always maintained about cycads was that they had about them an aura of the primeval, living fossils, throw backs to the era of dinosaurs. Now a recent molecular study of cycad evolution suggests that based upon a molecular clock the 300 or so modern species of cycad diversified from a common ancestor about 12 million years ago, more or less yesterday. True, cycads flourished during the Jurassic-Cretaceous some 200 to 65 million years ago, so it is an ancient lineage, but our extant cycads are not of this ancient stock. Individual cycads live so long, and grow so slowly that you can almost imagine them surviving for that long without any trouble, after all this young specimen of Encephalartos altensteinii from South Africa has been growing at the Royal Botanical Gardens at Kew since 1775. And then there was the time our house sitters left my pet cycads outside for the winter, treatment that greatly curtailed their potential longevity. Guess there’s always cinnamon fern. HT to Science News.

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