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The pollination strategy of the Ophrys is, like that of so many orchids, ingenious, intricate, wily, and seemingly improbable—so much so that proponents of intelligent design sometimes point to orchids as proof that the hand of a higher intelligence must be at work in nature. (And a rather sadistic intelligence at that.) Yet the peculiarities of orchid sex actually offer one of the great case studies of natural selection, as Charles Darwin himself under­stood. Darwin was fascinated by orchid pollination strategies, and though he was puzzled by the purpose of Ophrys's uncanny resemblance to bees (pseudocopulation wasn't observed until 1916), he taught us much of what we know about these plants in The Various Contrivances by Which Orchids are Fertilised by Insects, the volume he published immediately after The Origin of Species. Indeed, some scientists believe that had he published his orchid book first, the theory of natural selection might have encountered less skepticism than it did. Why? Because in orchids Darwin identified floral structures "as perfect as the most beautiful adaptations in the animal kingdom." He painstakingly demonstrated how even the most unlikely features of these flowers serve a reproductive function, and many of these structures are so perfectly adapted, both to the plant's requirements and the morphology of its pollinators, that they offered Darwin elegant proofs of his outlandish theory.

In one famous case, putting the final QED on Darwin's proof that evolution had tailored a flower to lure and exploit a specific pollinator had to wait a few decades. Attempting to explain why the star orchid of Madagascar would secrete a drop of nectar at the tail end of a foot-long floral spur, where no known pollinator could possibly get at it, Darwin hypoth­esized the existence of a moth with a 12-inch-long tongue, an unlikely creature that had never been observed. Vindication arrived a couple decades after Darwin's death, when entomologists unfurled the tongue of a newly discovered hawk moth and found that it measured nearly a foot long.

The orchid's baroque pollination strategies do raise challenging questions for the evolutionist, however. Since natural selection seldom rewards the unnecessary complication, why haven't all orchids stuck with the more straightforward pollination strategies based on nectar reward? And how in the world did their sexual practices get so elaborate? As for the hoodwinked pollinators, what, if anything, do they gain? If the answer is nothing but frustration, then why wouldn't natural selection eventually weed out insects so foolhardy as to spend their time mating with nature's version of the inflatable love doll?

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