Inside The New York Botanical Garden

Darwin’s Star Orchid

Posted in Around the Garden, Darwin's Garden, Gardens and Collections, The Orchid Show on March 29 2012, by Joyce Newman

Joyce H. Newman is the editor of Consumer Reports’, and has been a Garden Tour Guide with The New York Botanical Garden for the past six years.

Of the many thousands of orchids on display during the Orchid Show, the two most requested flowers are the vanilla orchid and what is known as Darwin’s orchid. However, due to their bloom schedules, neither is currently on display in the Conservatory. Those wishing to learn more about the vanilla orchid can scan a QR code on a sign in Conservatory gallery five (just off the Palm Dome to the left) to better understand the world’s only orchid-based flavoring. In the meantime, those wishing to learn about Darwin’s orchid can read on.

Several amazing Darwin star orchids have been blooming in the Rotunda located in the Library building at the NYBG. The exquisite ivory, star-shaped blossoms (Angraecum sesquipedale) are famous for their association with Charles Darwin and his theory of evolution.

The story goes that Darwin was sent a sample of the flower in 1862. Upon seeing its long, narrow, nectar tube, he predicted that there must be an insect with a very long proboscis (a tongue-like part) that could reach deep within the hollow space to “drink” the nectar at the bottom. In so doing the insect would bump into the flower’s sticky pollen, enabling its transfer from one flower to another.

But no such insect had ever been seen in Madagascar where the orchid came from, or anywhere else. And many scientists believed Darwin was wildly wrong, so he was ridiculed for his prediction.

Nonetheless, Darwin firmly believed that the star orchid had developed its long nectar tube as an adaptation to help ensure pollination because orchid flowers have their pollen in a single mass and cannot disperse it as other flowers do. The orchids need their specific insect pollinators to survive.

Sure enough, about four decades after Darwin’s prediction, an insect with the exact physical characteristics that Darwin had predicted was discovered. Called the Hawk Moth, its scientific name is Xanthopan morganii praedicta, which is Latin for ‘predicted moth’ in honor of Darwin. (Watch a nighttime video showing the moth interacting with the orchid.)

Darwin was a serious student of orchids, which he examined and tested as he developed his theory of evolution. He also wrote a book on his experiments with orchids entitled On the Various Contrivances by which British and Foreign Orchids are Fertilised by Insects. The star orchid turned out to be a perfect example of co-evolution, where two organisms–insect and flower–affect each other’s ability to grow and adapt.

According to NYBG’s Associate Curator of Glasshouse Collections, Jessica Clarke, it took a concentrated effort between herself, Fintan O’Sullivan, and Tim Barker–NYBG gardeners–to move the many Rotunda orchids from the Nolen Greenhouses where they had been cultivated successfully. She noted that the star orchids recently finished blooming–they do so from December or January through March–and have now been moved out of the glass case.

“It’s always fun to play with different color combinations and to arrange certain orchids so they are reaching toward the glass,” says Jessica. “It gives an ‘up close and personal’ feel for the visitors.”

The Orchid Show runs between now and April 22, boasting a number of lectures, how-tos, and intimate evening events to enjoy. Be sure to reserve your tickets!


Barbara Reiner said:

Thank you so much....been wondering about this orchid for several years. Your story is very interesting and sheds so much light on this specimen. Thrilled to gain all this extra knowledge.

Linda Warner said:

Which evolved first? The flower or the moth? How did one survive while waiting for the other!! What makes far more logical sense is that our Creator God made them at the same time, to keep each other alive. Why must man deny God's loving power & existence?

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