Rainforest Species Relationships

The relationships between various rainforest species makes for a fascinating study.

    Animals in rainforests contribute to their biodiversity. The term biodiversity or biological diversity may be understood in different ways.

The part biological refers to living organisms and the term diversity refers to divergence or variety.

When the word Variety comes about, it brings along with it the word Variations also.

  • Variations in Concepts, Thoughts and Perceptions about Biodiversity itself and

  • Variations in areas, numbers and all other measurable entities involved.
  • Tropical rainforests are homes for millions of different types of plants, animals, birds, insects and also forest dwelling people.

    Conservationists are alarmed over the fast depletion of world's tropical rainforests over the past few decades. If the destruction of the rainforests continues at the current pace, the rainforest animals and all other related entities will find it difficult to survive.

    That is, if the area of rainforests goes down, the number of related species like rainforest animals also go down.

    So, the question is :

    What action should all the concerned citizens of the world take in the matter?

    Since this page deals with animals of rainforests, let us try to find out the relationships between :

  • plants and animals

  • different animals themselves

  • animals and the indigenous forest people
  • by listing out the different types of rainforest animals first.

    By understanding these various relationships, we can get an idea about the…

    Variations in areas, numbers and all other measurable entities involved.

    Then we can get an idea about the actions needed to be taken by all concerned citizens of the world for the conservation of the rainforests.

    Rainforest animals fall into different categories as follows:·

  • Amphibians like frogs. They are capable of living both on land and in water.

  • Birds like Parrots and Toucans.

  • Insects like Ants, Butterflies and Caterpillars, of which butterflies having multi colored wings can fly.

  • Mammals like Apes, Gorillas, Elephants, Monkeys, Coatis, Sloths, Tapirs, Jaguars and Ocelots. Among the monkeys Capuchins, Spider Monkeys, Squillar Monkeys and Howler Monkeys are different varieties.

  • Reptiles like Alligators and Crocodiles, Lizards and Snakes.

  • Spiders like Tarantulas.




  • Scientists (ecologists, biologists, ethologists etc) explain the interactions or the interdependence between the different rainforest species by means of two terms:

    Symbiotic Relationships and Nitrogen Cycle.

    Symbiotic Relationship between two or more species is called:

  • Mutualism, if the relationship is beneficial for both of them.

  • Commensalism, if the relationship is beneficial for one species and neutral to the other, that is, neither beneficial nor harmful for the other species.

  • Parasitism or Predation, if the relationship benefits one species and harms the other species.

  • Neutralism, if there is no relationship between the species.

  • Amensalism, if the relationship is harmful for one species and neutral to the other.

  • Synnecrosis, if the relationship is harmful for both the species.
  • All living organisms require nitrogen compound for getting their necessary nutrients. Even though air contains nitrogen in abundance - 79% by volume, it cannot be used by organisms directly.

    It is an inert gas and needs to be converted into usable forms of nutrients for the "users" - whether they are plants, trees, animals or humans - by processing, either by natural biological process or by man made industrial processing.

    After the "users" consume their nutrients and eject their excrements to the atmosphere, they must be further acted upon by the natural biological process or the industrial processing to recycle the excrements back into nitrogen again before it can be passed on to the atmosphere.

    Plants require nitrogen compound in the form of ammonia, urea etc. They get them from the soil through their roots by absorption.

    "Nitrogen-fixing" bacteria like rhizobia and mycorrhizae fungi enable the roots of the trees and plants to get the required nitrogen compound from the soil.

    This is a mutually beneficial symbiotic relationship between the trees and the fungi,

    since the plants get their nutrients from the soil through the fungi and

    mycorrhizal fungi get their nutrients in the form of sugars, starches, proteins etc from the plant roots.

    Animals are either:

    Herbivores - which means that they are plant or fruit eaters Or

    Carnivores - which means that they are meat eators - that is they hunt other animals for their meals Or

    Scavengers - which means that they eat dead animals.

    This way the animals get their nitrogen compound either from plants directly, if they are herbivores or from other animals who are plant eators, if they are either carnivores or scavengers.

    The animal excrements are decomposed by bacteria and fungi in the soil to form various nitrogen compounds like ammonia, nitrites, nitrates etc

    by ammonification Or

    nitrification processes for assimilation by the trees and plants.

    Or

    by denitrifying bacteria to decompose the nitrogen compound, so that it can go back to the atmosphere as nitrogen again.

    This completes the Nitrogen Cycle.

    Thus there is a mutually beneficial symbiotic relationship between the plants and the animals.

    This mutually beneficial symbiotic relationship between the plants and the animals can be seen in the following different ways:

    The trees produce fruits, nuts, and flowers and possess branches, leaves, roots etc.

    The animal excrements come in one of three forms:

    The animal may eat the the fruit and spit the seed on to the soilHere the animal acts as seed disperser.

    Or

    it may not eat it at all and simply throw the entire thing on to the ground

    Or

    the whole thing may be eaten and the excrements are ejected to the ground later on.

    Normally, the winds would also help in blowing seeds to other areas and parts if the area is a normal agricultural land or an open area and if the seeds are small in sizes.

    In the rainforests, the situation is slightly different. The thick canopy provides such a dense and packed covering over the forest floor that there is only a light wind flow, so they may not be able to disperse the large seeds.

    In the Australian rainforests the birds Cassowaries tackle this problem satisfactorily, since they are capable of carrying seeds, which are too large to be carried by winds or other birds to distant parts of the rainforests.

    The birds travel to various areas. They eat different fruits, all kinds of fruits or to put it correctly, they swallow the whole fruits.

    The seeds pass through their digestive system to the soil without any damage, so that new vegetation can be produced and grown there.

    Thus these birds share a mutually beneficial symbiotic relationship with the trees of the Australian rainforests, by carrying the vegetation to distant parts.



    Elephants are herbivores.

    Food gathering is a major activity for the elephants, since they can digest hardly 40% of the food ingested by them and the balance 60% gets excreted without being digested.

    Dung beetles and termites act as the dispersers in this case by taking them (the elephant excretions) below the ground and distributing the nutrients by exposing dung to soil microbes, plant roots, earthworms etc, thus helping the soil to become fertile and facilitating nutrient recycling.

    They also improve water infiltration and aeration of soil by creating a network of underground tunnels.

    Elephants eat upto 270 Kg of food per day including grass, leaves, twigs, roots, fruits, nuts, flowers etc. In that process, the trees get uprooted and pulled down, thereby causing destruction of the trees.

    In a way, it may be a cause for concern, since elephants have the habit of searching for their meals for almost two thirds of the day. In this search, they move over great distances.

    If we consider the fact that elephants normally move in herds of about 100 in their movements from place to place, imagine the results of the movement of a large number of elephants moving, pulling down the trees, eating their contents and throwing the debris all over the path.

    This creates deadwood and decaying trees and plants. But saproxylic or deadwood dependent micro organisms like insects and fungi are delighted at this situation, since they have the ability to convert this deadwood and decayed plants into proteins, thus providing food for various birds and animals.

    Hence if we look at it in another way, this helps in clearing the area, as the existing trees and plants are pulled down, so that new plants and trees can sprout in their places.

    Due to their heavy weights, when the elephants walk on the cleared ground in such herds, they create depressions on the ground, which can collect rainfall for the benefit of the smaller animals.

    When they move this way, they terrorize smaller species like insects, amphibians or reptiles, which try to run away from their shelters scared by the approach of the elephants but they end up as meals for the birds, thus signifying two different aspects of symbiotic relationships :

  • Mutualism between the elephants, plants, trees and the birds, but

  • Predation between the birds and the insects or reptiles.

  • Rhinoceros shares a symbiotic relationship with oxpeckers. The oxpecker eats ticks it finds on the rhino and so they are also called tick birds. The bird emits noises to warn the rhino of danger.
  • Even though Crocodiles are predators, they share a mutually beneficial symbiotic relationship with the Egyptian Plover, since the bird feeds on parasites that attack them in the mouth.

    Here are some examples of Predatory relationships between certain animals.

    Jaguars are solitary hunters since they do not associate with one another outside the breeding season. Their prey is a mixed bag containing a variety of animals like tapirs, deer, frogs, mice and fish.

    Ocelots possess keen eye sight, they confine themselves to a fixed territory and usually hunt animals which are smaller than them - mostly monkeys, snakes, rodents and birds.

    Crocodiles are lazy hunters. They prefer to wait for their prey: fish, birds, mammals and occasionally, human. Since they are cold blooded animals, they can survive without any food for a long time, but if they become too much hungry and if they do not get any other animal for their feed, they may turn cannibalistic when large crocodiles eat smaller ones.

    Although Sloths are herbivores and normally eat only leaves, they also sometimes eat insects and lizards.

    Coatis are insectivores, that is, they eat insects normally, but they also eat fruit.

    Frog, Lizard, Bat and Spider are other examples of insectivores.

    Cassowaries eat mainly fruits, but they also eat snakes, frogs, snails, insects and fungi.

    Frogs are known to catch fast flying insects by protruding their sticky tongues out. Small frogs eat mosquitoes, earthworms and fish. Big frogs eat mice, while some of the big ones eat small frogs.While frogs are predators themselves as found above, they themselves are hunted by other predators like snakes, otters, coatis etc.

    Lizards feed on insects or rodents.

    Anaconda eats birds and mammals.

    When there is a Predatory symbiotic relationship between any two animals, there are bound to be strategies for both of them,

  • Hunting Strategies of the predator animal, which include Chase, Stalk and Ambush and

  • Defensive Strategies of the prey animal, which include Camouflage, Mimicry, Scaring, Hiding etc.

    Both the animals adapt to their circumstances in devising their strategies.

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