PLANTS ARE FASCINATING
by Whit Gibbons
January 8, 2006
One of my
former botany teachers, Joab Thomas, once told me that my columns on ecology
had too few plant examples compared to animals. My rationale is that people
are more interested in animals than in plants, primarily because animals
are action figures, whereas plants just sit there. Plants are mostly inert,
unless the wind is blowing. Nonetheless, Thomas is an excellent botanist
whose advice is worth listening to. Some exciting plants do exist in nature,
and providing a few examples will not be a bad thing.
of TV nature shows are captivated by carnivores. Lions, pythons, and sharks
get more than their fair share of attention. But accounts of animals eating
animals fall into the “dog bites man” category. For a twist
of the “man bites dog” variety, we need to look at stories
of plants eating animals. And indeed millions of animals are eaten alive
by plants every year.
plants used to be called insectivorous plants because insects make up
the bulk of their diet. But botanists now refer to them as carnivorous
plants because animals besides insects are on the menu, including small
birds, frogs, and mammals. Plants that capture and digest animals occur
in many parts of the world, and several kinds can be found in North America.
Pitcher plants, in which insects fall into a highly effective pitfall
trap, are among the best known. In some, the column, or “pitcher,”
is only a few inches high, but it can be almost three feet tall in the
yellow trumpet pitcher plants. With downward-pointing hairs around the
lip of the column and digestive liquor at the bottom of the flask, pitcher
plants mean certain death for many insects. The bug that makes a misstep
over the edge of the tube will soon become part of the plant world, as
it is digested and absorbed.
spectacular pitcher plants are from Mt. Kinabalu National Park in Borneo,
a region with the greatest concentration of pitcher plant species in the
world. One of these, the rajah pitcher plant, has tubular flasks large
enough to capture rats. These carnivorous plants hold more than a quart
of digestive fluid. Unfortunately, poaching of these awesome giant pitcher
plants has been a problem, and few remain in the wild compared to their
abundance only a few decades ago.
unusual group of plants produce their own heat internally, a trait usually
reserved for birds, mammals, and a few other animals. Perhaps the best
known U.S. plant with heat producing properties is the eastern skunk cabbage.
In the Northeast, skunk cabbages are among the earliest plants emerging
in the spring, often pushing directly up through a covering of snow that
is melted by their generated heat. Some skunk cabbages have been reported
to raise their temperature 45 degrees higher than their environment.
heat-producing plant is the voodoo lily, a tropical species of Southeast
Asia. With a beauty typical of other lilies, the voodoo lily has a striking
purple flower and reaches a height of almost three feet. Despite their
ornamental appearance, voodoo lilies have a trait that might diminish
their popularity in the garden. During the period of pollination, the
flowers heat up, with temperatures inside a flower in the cool shade sometimes
reaching temperatures of 110°F. At this time, they smell like rotting
we are often interested in with regard to animals is their size. How long
is an anaconda? How high can a grizzly bear stand? How much does the bass
you caught weigh? What about plants--what is the biggest flower in the
world? The answer: Rafflesia. Found in Indonesian rainforests this plant
truly qualifies as bizarre, because all you see is flower. It has no leaves,
no limbs, no roots. In fact, Rafflesia does not even have chlorophyll.
It is just a giant, eye-catching flower that can be more than three feet
in diameter and weigh more than 40 pounds. It has parasitic filaments
that feed off the roots of a particular species of vine.
these plants would make good Discovery Channel action videos, but all
serve as superb examples of the diversity of life and the many secrets
and mysteries that await our understanding.
you have an environmental question or comment, email