Ever wonder why some trees have beautiful flowers and others don't seem to have flowers at all? Well, like so many things in nature, it has to do with reproduction. Trees like oaks and pecans aren't flowerless, it's just that many people don't recognize the reproductive parts as flowers. Take a close look in springtime at oaks or cottonwoods, and you may spot catkins, clusters looking vaguely like caterpillars and consisting of insignificant-looking flowers. So they really do have flowers, but why aren't they showy? Really, it's quite simple; they are beholden to nothing but the wind to carry their pollen from tree to tree.
On the other hand, wind is notoriously fickle, and if a plant can
entice an animal to carry pollen to another of its kind, fertilization is more certain.
And that's what flowers are—no, not necessarily an appeal to beauty, but a blatant
advertisement: "Here I am, I have nectar for you", but of course not
mentioning that, as with all advertisers, it expects to gain. Perhaps unexpectedly
though, usually a fair trade for both.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.