north american native orchid journal - at The Culture Sheet

Folsom: A CASE FOR EVOLUTION
the mechanisms and strategies that North American orchids have
developed to cope with these events that have changed their
world.
Let us examine the pollinization processes that orchids
have devised to ensure their survival. This process has evolved to
be very specific in many orchid species. They have unique
techniques and attract only certain agents of pollination.
As everyone knows orchids have 3 sepals and 3 petals with
the stamen(s) and pistil fused into a column. The three petals
consist of two lateral petals and the third petal is formed into a lip.
The lip acts as both an attractant and landing platform for many
pollinators. The many genera and species of orchids have lips in
varying size, shape, and colors that entice many kinds of
pollinators including butterflies, moths, bees, wasps, flies, and
gnats, to name a few. Some orchids use scent, often at a specific
time of day or night, to attract the pollinators, others brilliant
color, and still others dynamic patterns. Many botanists have
watched orchids hoping to discover the actual pollinators or kinds
of actions that were required to ensure fertilization. Roger
Hammer, of Homestead, Florida, spent several nights in the
Fakahatchee Swamp to observe the giant nocturnal moth that
pollinates the ghost orchid, Dendrophylax lindenii (Hammer, 1996).
Calopogons are constructed in
such a way that their lip is
uppermost. With the lip in this
position when the heavy bee
pollinator attaches itself to the
attractive yellow beard (a false
pollen) it snaps down with the bee’s
weight and deposits the pollen
brought from the bee’s visit to
another blossom into contact with
the flower’s stigmatic surface, therefore effecting pollination.
Some species even allow rain, by assisting the transfer of the
pollen, to act as the agent for pollination (Catling, 1980).
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