Christian James
Keith Z. Dalman

Written Report

Community
Structure and Functions

            A community is a group of organisms
of different species that live in a same area which they interact to each
other.  All species rely on other species in some way in order to survive.
They may rely on other species for food, shelter or to help them
reproduce. For example, a bee helps the flower to pollinate and the flower
helps the bee to survive. Species are not independent they are interdependent
to each other. In the community where different species lives is called a
habitat. It is where the natural home or environment of an animals, plants and
other species.  For example; Dessert,
oceans, forest, farm and many more. Each habitat has different kinds of animals
and plants living there which they interact to each other. However there is a
difference between a community and habitat, a habitat is where organisms of
different species lives while a community is a group of organisms living in the
same area.

According
on our research biodiversity is a term that describes the variety of living
beings on earth. It is described as degree of variation life. It includes diversity within species, between species
and among ecosystems. The concept also covers how this change from one location
to another and over time.

            In
the graph living planet index, an indicator of a state of the world’s
biodiversity which measures trends in populations of vertebrate species living
in terrestrial, freshwater, and marine ecosystems. As we have seen in the graph
the number of population  slowly
declining through the years, from 1970 to 2000 the population of marine
species, terrestrial species and freshwater species decreases. One of the
reason of this is human activities that causes distractions to the habitat of
other species. Examples of human activities that often changes and destroys the
habitats of  plants and animals are
illegal logging, Illegal hunting and killing of 
animals, and Polluting the environment. Another reason is that we humans
take more space on earth for our homes and expansions of Cities and all. All of
this human activities take resources and habitats of  animals and plants for them to survive.

            Competition
is typically considered the interaction of 
organisms that battles for a common resource. Where there is
competition, one or both of the organisms will lack resource. Competition can
be defined as inter-specific competition 
or intra-specific competition. Inter-specific competition  is form of competition where individuals of different
species compete for the same resources in the ecosystem. An example of
inter-specific competition is a farm of rice paddies with weeds growing in the
field, they compete for the energy that sun gives. On the other hand
intra-specific competition is a form of competition between organisms of the
same species compete for the same resource. An example of this competition ,
are cows competing grass for food for them to survive.

On an individual organism level, competition can occur
as Exploitative and interference competition. Exploitative competition is a
form of competition when all individuals have the equal access to the resource
, but they differ on how fast or how they can exploit it. Example for this
competition are the broilers in the farm where they are given equal access of
the feeds. While interference competition is a form of competition when certain
individuals are able to restrict or prevent access of others to the resources and
so control the use of it.

Interaction among Biotic communities it is the
interaction between different organisms in an environment. There  are various types of close relationships
between organisms of different species such as:

–         
Predator/Prey
relationships when one organism killed by other organism just like spiders eats
flies.

–         
Producer
and consumer relationship where in plants produces food for animals like cow,
carabao and more.

–         
Commensalism
is an interaction of two species where in one species benefits while the other
is not affected. Ex. Carabao and bird where the bird find food through
carabao’s lice.

–         
Mutualism
an interact       ion between two species
wherein the two benefits.

–         
Parasitism
is an interaction between two species wherein one species benefits and other is
harmed.