This document discusses community ecology and the relationships between organisms within a community. It defines community ecology as the study of interactions among species and with the abiotic environment. Different types of symbiotic relationships are classified, including mutualism, commensalism, parasitism, amensalism, predation, and competition. Each relationship is defined based on whether it benefits, harms, or has no effect on the interacting species.

2. COMMUNITY ECOLOGY
• It is the branch or division of
ecology that deals with the study of
the interactions among species and
interactions with the abiotic
environment.

3. COMMUNITY ECOLOGY
• A community is composed of all
the population of a given area.
• It is a group of population
interacting with one another within
the same environment..

4. COMMUNITY ECOLOGY
• A community ecologists might
consider the ways in which animals
and plants with a forest affect one
another’s growth.

5. Rainforest Community
• It includes many different species of trees ,
thick vines called lianas ,and epiphytes (orchids,
cacti, ferns).

6. Rainforest Community
• A wide variety of animal species inhabit
tropical rainforests. Mammals such as monkeys,
reptiles, amphibians, colorful birds and insects.

7. RELATIONSHIP AMONG
ORGANISMS
• Each relationship exhibits a distinctive
behavior that one organism affects
another.
• Symbiotic relationship are those in
which two entire different organisms live
in a close association that benefits at
least one of them.

8. Classifications of
Symbioses
Mutualism
Commensalism
Parasitism
Amensalism
Predation
Competition

9. Classifications of
Symbioses
Mutualism - Is a give-and-
take relationship.
Both participating species
benefited and obligatory(+,
+)
example : oxpeker and
zebra

10. Classifications of
Symbioses
Commensalism - Is a symbiotic
relationship that benefits one species
and neither hurts nor helps the other.
Thus a positive-neutral (+ , 0).
Example: Epiphytes get sunlight and
nutrients by living on the host plant

11. Classifications of
Symbioses
Parasitism - a relationship which one
organism benefits and the other is
harmed, and thus a positive-negative (
+,- ) interaction.
 The one benefited is called parasite,
while the organism that is harmed is
host.

12. Classifications of
Symbioses
Parasitism
PARASITES are usually smaller than their hosts and are classified
into two:
ECTOPARASITE (external parasite)
Fleas
Ticks
Mites
ENDOPARASITE
Tapeworms
Roundworms

13. Classifications of
Symbioses
Amensalism - One organism is
inhibited or destroyed and the other is
not affected.
 Thus, ( - , o )
Example: When cattle trample on grass,
the grass is crushed.However, the cattle
do not benefit from this action nor is
harmed in the process.

14. Classifications of
Symbioses
COMPETITION
 A relationship which organisms struggle with
each other to obtain limited resources.
 Such as food, water, sunlight, territory, shelter,
nesting sites, and so are the things organisms
needs to survive.
 Defined as double negative ( - , -) interaction.

15. Classifications of
Symbioses
PREDATION
 Another type of relationship in a community.
 Occurs when one organism benefits at the
expense of another.
 This is a positive-negative (+ , - ) interaction.
 Predator species benefits, while the prey
species is harmed.