northanger (northanger) wrote,
northanger
northanger

adaptation

The star-of-Bethlehem or comet orchid (Angraecum sesquipedale Thouars) is a native of Madagascar. The orchid comes into bloom starting in December. The comet orchid is phalenophilus [fal en of' e lus], "moth-loving", the waxy white flowers are scentless during the day and both highly visible and fragrant after dark to attract the night-flyers. Each flower has a remarkable spur or nectary up to 30 centimeters (12 inches) long, but only the tip of the spur contains nectar. In 1862, Charles Darwin wrote to Joseph Hooker, musing on what could suck the nectar from such a flower. Darwin predicted an insect with an extremely long proboscis would be discovered and that it would be the major pollinator of the orchid. [How did an orchid 'shape' a prediction?]

Angraecum sesquipedale – comet orchid. The John Day Scrapbooks. [The Royal Botanic Gardens, Kew]

The hawkmoths, which in flight and size can be easily confused with hummingbirds, are among the most important nocturnal pollinators. In Madagascar, the extraordinary number and diversity of long-spurred orchids likely evolved in unison with the diverse group of long-tongued archaic hawkmoths found on this isolated island. Darwin suspected a relationship between hawkmoths and orchids existed decades before it was observed. After studying the long nectar reservoirs of the night-blooming orchid Angraecum sesquipedale, Darwin predicted that it would be pollinated by a nocturnal hawkmoth with a tongue ten to eleven inches long. The Xanthopan morgani predicta hawkmoth, with its twelve-inch proboscis, was described 40 years later. In this case, the adaptation extends beyond the custom fit of the moth’s tongue to the orchid’s flower structure. The orchid’s pollen adheres to the moth’s head by means of a sticky pad, to which pollen is connected with elastic cord. By the time the hawkmoth visits another plant, the cord has dried up, and the pollen is successfully transferred. [Night Bloomers And Their Matchmakers]

Of course, I saved the best orchid for last. The orchid known as the "Christmas Star" or "The Star of Bethlehem Orchid" is Angraecum sesquipedale. This orchid has to be one of the most fabulous looking I have ever seen! Charles Darwin discovered this orchid in 1850 living in the trees of Madagascar. The plant does not have pseudobulbs unlike many other of the orchids. Its leaves look like a large fan and it can grow to be over 15" (38cm) tall. The blossoms are star-shaped and reach up to 7" (17.8cm) in diameter. The blooms are a waxy white to greenish white in color. Each blossom also has a spur that begins at the bottom of the bloom which can reach over 12" (30.5cm) in length. At the base of this spectacular spur is the sweet nectar that attracts the pollinator. For over fifty years, Darwin's theory that a moth was the pollinator of this strange and wondrous orchid was laughed at and ridiculed. No one believed such a moth could exist. This particular moth would have to have an apparatus such as a proboscis that was over 12" (30.5cm) in length to reach the nectar at the bottom of the spur. The moth would also have to be nocturnal since this orchid is only fragrant at night. It wasn't until 50 years later that such a moth was actually discovered and proven it was in fact the pollinator. The moth is now known as the "Hawk-Moth" Xanthopan morgani praedicta. This moth has a coil-like structure (proboscis)that uncurls to a length over 12" (30.5cm), exactly what is needed to reach the sweet nectar that waits at the bottom of the spur! This insect has a wing span of 13 to 15 cm, of the is color of a dead leaf. [Christmas In the Orchid Garden]

Such unusual pollination schemes have long entranced biologists. The great evolutionist Charles Darwin was so taken with the flowers that in 1877 he published a thick book devoted to THE VARIOUS CONTRIVANCES BY WHICH ORCHIDS ARE FERTILISED BY INSECTS. In it, he noted that some orchids appear to rely on just one specific pollinator -- a particular species of moth, for instance -- for survival. Modern researchers call this specialized biological embrace of two species "co-evolution." But co-evolution has both benefits and risks. The benefit is that both partners can specialize and don't have to waste energy finding other ways to reproduce. The peril is becoming too reliant on a single partner. If one half of the co-evolved pair becomes extinct, the other is surely doomed as well. Darwin's insights into co-evolution allowed him to foretell the discovery of a new species. In a famous example, he described an orchid from Madagascar that had a foot-deep nectar well that kept the sweet liquid far out of reach of all known butterflies and moths. But the existence of the flower led him to predict the existence of a specialized moth with a foot-long proboscis that, like a straw, could reach the deep reward. Indeed, after Darwin's death, researchers discovered just such an insect, and named it the "Predicta moth" in honor of Darwin's educated guess. [Beautiful Deceivers]

Angraecum Sesquipidale. Beauty! God! Darwin wrote about this one. Charles Darwin? Evolution guy? Hello! See that nectory all the way down there? Darwin hypothesized a moth, with a nose 12 inches long would pollinate it. Everyone thought he was a loon. Then sure enough, they found this moth, with a 12 inch proboscis. Proboscis means nose by the way. Point is, what's so wonderful, is that every one of these flowers has a specific relationship with the insect that pollinates it. There's a certain orchid that looks exactly like a certain insect so that this insect is drawn to this flower, its double, its soul mate, and wants nothing more than to make love to it. Then after, the insect flies off, spots another soul mate flower, and makes love to it, thus pollinating it. And neither the flower, nor the insect, will understand the significance of their lovemaking. And how could they know, that because of their little dance, that the world lives by simply doing what they're designed to do, so that something large, and magnificent happens. And in this sense, they show us how to live, how the only barometer you have is your heart. Now when you spot your flower, you can't let anything get in your way. [John Laroche, from Adaptation]

In 1994, I headed down to Florida to investigate the story of John Laroche, an eccentric plant dealer who had been arrested along with a crew of Seminoles for poaching rare orchids out of the a South Florida swamp. I never imagined that I would end up spending the next two years shadowing Laroche and exploring the odd, passionate world of orchid fanatics. I certainly never imagined that I would willingly hike through the swamps of South Florida - but that's what writing a book does to you. I found myself as passionate about the project as the orchid fanatics were about their flowers, and that is ultimately what the book is about. I'm proud to report that the book was a New York Times bestseller, a Barnes and Noble Discover book, a Borders New Voices selection, an honoree in the American Library Association and New York Public Library books-of-the-year selections, and the subject of the upcoming movie Adaptation. [The Orchid Thief]

I want to make a confession: I am passionately and uncontrollably in love with Dick Cheney. Lynne, I'm sorry; if I could help it I would. It's just something about him--the strength, the silence, the frank and unabashed baldness, the mystery, the unknowability, the man, the myth, the Vice-Presidentialness of him. It's wild, it's mad, it's hunger, we're crazy like a couple of kids in the last week of school when the teacher is out with a communicable disease and the substitute is a moron and we've sneaked out to the playground--you know, that kind of crazy. There is nothing about him that doesn't transport me to a different, deeper, more womanly place. In a funny way, the undisclosed-safe-location weekends just add a frisson of stolen pleasure to the roiling emotions we share. There. I've said it. I can't hide it anymore. [Tainted Love]

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