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Much like urban centers throughout the world,
in crowded ecosystems that are densely populated by vegetation,
space and resources can be limited. But just like their human counterparts, some plants have found
a novel way to survive - by making an entirely new habitat for themselves high above the ground.
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In South Florida's humid cypress swamps and hardwood hammocks,
abundant water, warm temperatures, and ground that is rich in biota all culminate in ideal
conditions for the growth of plants.
But this habitat is so rich and so conducive to plant life, that in many cases,
every square inch of available land is occupied.
As in every ecosystem, however, competition for resources drives new and unique
adaptations from the organisms within it.
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When access to area on the ground is limited, some species of plants have found success by making
their home above it.
This broad group of plants is known as epiphytes.
Found growing on top of trees or other larger natural objects, sometimes several stories
above any soil, the very existence of epiphytes can be hard to believe. With such precarious placement high among the swamp's canopy, the seeds of epiphytes like
this airplant are transported to the branches of their host plant by the wind.
The roots of a young airplant then attach directly to the host plant to provide a secure base for growth.
Ferns, on the other hand, are used to having soil in which to place their roots,
but they too can become epiphytes by taking root in thick layers of moss, which
act as a substitute for soil.
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The ground, however, traditionally serves more than one purpose for a plant.
In addition to anchoring the plant, the ground acts as its source for water and other much-needed nutrients.
When a plant has no access to the ground, these important resources must be obtained by some other means.
While water is in no short supply in the cypress swamp, epiphytes have to be able
to collect it straight from the air before it ever hits the ground.
Because of this, the structure of an epiphyte is more similar to that of a desert plant than
that of its neighbors.
Funnel-shaped leaves direct rainwater into a large reservoir in some epiphytes,
while others possess thick roots and stems to quickly absorb and hold rain and fog.
Some epiphytes even have the ability to obtain their water directly from the air itself.
Gathering nutrients may pose an even greater challenge for epiphytes,
and the adaptations they've developed in response may be equally as extraordinary.
The same reservoirs that enable some epiphytes to store water may also be a component
in the process of receiving nutrients.
Water stored in this reservoir can attract small tree-dwelling organisms like frogs and insects,
the prey of larger swamp inhabitants like lizards.
When preyed upon, the remains of frogs, insects, and their eggs and larvae can provide
decomposing organic material from which the epiphyte can derive nutrients.
But this isn't the only way in which epiphytes can fulfill their nutritional requirements.
Many epiphytes absorb nutrients from decaying material found on the host plant itself. 04:38.000 --. 04:44.000 But the most astonishing method utilized be epiphytes involves one of nature's most
powerful and unpredictable forces.
Thunderstorms are a common occurrence in the swamps of southeastern North America.
As such, lightning can strike with frequency and intensity.
Lightning, like fire, instigates a reaction that ultimately leaves nitrogen in the environment.
Nitrogen is one the most essential nutrients for plants, and when found around a host plant,
can be utilized by an epiphyte, which would normally be forced to utilize nitrogen from the ground.
In all of their many unique adaptations, epiphytes have taken ecological competition to
extreme ends, and pushed the boundaries of what's possible.
Cypress swamp, hardwood hammock, and other environments like them foster this rare
and intriguing group of plants.
Numerous mechanisms that are common to almost all other plants have been nearly reinvented 05:51.000 --. 05:58.000 by those that live in a habitat unlike any other, a habitat in the air.
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