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			The Ecology of a Rain Forest

				By The Cruiser...

Here you go, haker douds.  Your very own onors byologie reep0rt.

     In 1980, the estimated amount of rain forests in the world was 40,000
square miles.  This number decreases each year by roughly 1,000 square miles
due to construction and the resources being used for profit.  It is too bad,
because the rain forest is one of the most beautiful places on earth.  It is
the most diverse, containing the most species of living things, much more than
anywhere else, and most have yet to be identified.  All rain forests are
located on earth's "green belt", that is, the area roughly around the equator
that covers all the area from Mexico and the northern area of South America, to
Africa, to India, streching out to Indonesia, the northern tip of Australia and
all the way to New Guinea.  This area is heavily covered with flora and fauna,
and it abounds with life.  In a rain forest, it is very wet and it rains every
day or every other day very heavily.  There is a high and steady level of heat
and moisture.  There are some general layers to the rain forest.  It starts
135 feet up in the air, with the lofty crowns of the tallest trees in the
jungle.  They take the most light, heat, rain and the most punishment from the
winds.	Woodpeckers hunt insects in this layer, and also the black and white
Colobus monkey can be found here, ready to lauch into the air, using his
specially developed tail as a rudder to guide his flight.  Beneath this is the
second layer of trees, whose crowns form a forest canopy.  Rain filters
through this canopy, and the top sides of the crowns hold a large amount of
ferns and other small plants whose roots never touch soil.  They live off the
water and nutrients held in the small pockets of the leaves and branches.  Tree
frogs and chimpanzees live here, burrowing holes to live in the vast
vegetation.  The third layer is called the "understory".  This grows beneath
the canopy.  The gorilla makes this his regular hangout, also pythons lie here
waiting for prey.  The dim forest floor teems with life.  Termites and ants
feed on all the decomposing matter on the ground, and elephants make their
way down a path of moss.  Butterflies move silently by, and the air is still
and very humid.  These are the layers that make up the rain forest's complex
ecology.  In the rest of the essay I will describe some of the life forms found
in the rain forest, and ways they affect the environment.  In the rain forest,
plants develop poisonous alkaloids to protect against insects, and insects
develop complex digestive chemistry to overcome these poisons.	Some of these
plant alkaloids give native indians great poisons for darts, and to cancer
researchers hope for a new medicine.  The rain forest root systems are so
efficient that almost all of the nutrients in decaying plants are recycled
into new ones.	Most roots are found within three inches of the surface in
heavy clay or at the surface in sandy soils.  Tiny rootlets grow up and attach
themsleves to leaves.  When the leaf decays, miniscule fungi on the rootlets
take over and send threadlike projections into the leaf which absorbs all of
the leaf's nutrient material.  The phosphorous that the fungi produces is
taken by the root, and in turn gives the fungus sugars from the tree.  Also,
termites and ants break down the forest litter.  In a small lake in the middle
of the rain forest, a small lizard skims across the water away from danagerous
prey and attacks its own victim by suprise, yet another marvel of the tropical
rain forest.  Mutualism occurs in the jungle with a specialized ant and a
swollen-thorn acacia.  The acacia provides budlike leaflet tips which are
called Beltian bodies, which the ants give to their young for food.  The
insects hollow out the tree's thorns when soft and green and raise their young
inside.  The acacia doesn't have chemical defenses to repel dangerous and
damaging insects and demands pure sunlight for proper growth.  The ants patrol
the tree day and night.  If any insect lands on the tree, they bite it with a
poisonous sting.  They also attack plants that grow onto the tree, such as a
vine.  In this case, they would attack the vine at it's base and pull it off
the tree.  There are also small leaf-cutting ants in the jungle that cut a
portion of a leaf, bring it to their home, and chew it to a pulp and inject a
body fluid to create a wet mulch.  On this mulch grows the only food of this
particular ant -- a fungus that has only one species.  The mysterious part
about this is that any spores that could develop on the mulch and contaminate
it don't develop.  Paper wasps in the rain forest have to bail out their home
after a heavy shower.  They lap up a mouthful of water from the colony, and
then spit it out onto the forest floor.  They also coat the small stalk that
attaches the nest to the branch of a tree with a sticky black sectretion that
repels some ants.  But there are still some predators, such as jungle katydids
which eat the leaves, and some species of ants that are not repelled by the
black secretion.  In one rain forest, there is a kind of toad that is
voiceless.  So for the male to attract a mate, nature gave it a very noticeable
characteristic -- a flourescent orange color, which is unmistakable.  The
females are blackish green with scarlet spots on them.	In April and May,
mating takes place.  Where pools are formed on the forest floor by water
trickling down trees, females lay around 200 eggs.  After the males fertilize
them, the embryos live in their aquatic world for about two weeks, then after
that they hatch and mature.  This species was discovered in 1964 and it helped
win government protection for Monteverde, which is the place where these frogs
can be found.  Biologist Jay M. Savage, amazed by the frogs, once wrote "I must
confess. . .my. . .disbelief and suspicion that someone had dipped the examples
in enamel paint."  There are other species of frogs, such as the green leaf
frog, whose green body and glowing red eyes is an incredible sight.  They
extrude and fertilize their eggs on a leaf over water.	Young that are ready to
leave their embryo drop into the water below.  Also the poison-arrow frog is
an interesting variety.  The males battle for dominance and mates.  Two can
struggle for hours until one give up and croaks "uncle".  Their color warns
predators of their composition which could prove toxic for snakes and other
such beasties.	The Dendrobates Granuliferus frog doesn't have young that
develop in water.  Instead, the tadpoles cling to the mother's wet back.  She
transports them this way from place to place, usually depositing them in a cup
of rainwater in a high branch safe from predators.  She immerses herself in the
water at first until the young let go of her body and swim into the water.  A
rare bird found only in rain forests, the quetzal, is a beautiful sight.  They
have long colorful tails which have long been worn by royalty of the Colombian
Indians, who called the birds sacred.  It is beautiful animals like these that
might start spur nations into preserving more of their rain forests, in hopes
of keeping one of the most complex and interesting ecologies on earth.


:)