The Orchid Room at the United States Botanic Garden
During today’s lunchtime bike ride, I started off the month by once again stopping by the United States Botanic Garden, located near the U.S. Capitol Building at 1st Street & Maryland Avenue (MAP) in Downtown D.C. In operation since 1850 and in its current location since 1933, the United States Botanic Gardens houses numerous themed rooms, and is home to almost 10,000 living specimens, some of them over 165 years old. During this visit I stopped by to spend some time appreciating the flowering plants in The Orchid Room, which are presented annually in collaboration with the Smithsonian Gardens Orchid Collection.
With blooms that are often colorful and fragrant, orchids are easily distinguished from other plants based on some very evident, shared derived characteristics, know as apomorphies. Among these are: bilateral symmetry of the flower, also referred to as zygomorphism; many resupinate flowers; a nearly always highly modified petal orlabellum; fused stamens and carpels, and; extremely small seeds.
Orchids showcase a wide spectrum of color, shape, size, habitat, and scent, and with approximately 30,000 species are one of the two largest and diverse families of flowering plants. The other are daisies. And over the past 80 million years, orchids have successfully colonized every continent except Antarctica, and almost every conceivable habitat, from remote Mediterranean mountaintops to living rooms around the world.
And one of the secrets to their success is unusual and highly specialized pollination methods. Many orchids provide food for insects and birds and even more have symbiotic relationships with micro-organisms that assist with nutrient cycling in the ecosystem. Butterflies and moths are enticed to pollinate orchids that resemble flowers they normally feed on or orchids that provide a landing area and sufficient nectar rewards. Moth-pollinated orchids tend to have strong nighttime fragrances to attract their pollinators from great distances. And in higher-elevation cloud forests where there are fewer pollinators, some orchids have evolved to have brightly colored tubular flowers with large nectar rewards to entice hummingbirds.
But the most unusual method is employed by the Ophrys apifera, also known as the “bee” orchid. The bee orchid, or the “prostitute” orchid as it is less politely called by some botanists, has what is probably the most unusual pollination method. It can best be described as sex, or pseudo-sex. Small but flamboyant, the bee orchid is one of nature’s great mimics. Perched within the large pink sepals are petals shaped and colored like a visiting bee. The pink sepals look like wings and there are furry, brown lips that have yellow markings just like a bee. But the deception goes further than visual appearance alone. The flower takes on the tactile experience, and even emits the scent, of a female bee. But the orchid offers the bee no nectar reward or pollen meal. Instead, it attracts amorous male bee pollinators with the promise of bee sex to ensure its pollination.
So the next time you are walking through The Orchid Room, or admiring the beauty of some orchids, keep in mind that there is often more to them than meets the eye.
[Click on the photos to view the full-size versions]
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