THE SCIENCE OF
ECOLOGY
The Scope of Ecology
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Derived from the Greek word; oikos meaning
“house” or “place to live” and logus meaning “study
of”
Ecology is the study of interactions between
organisms and their environment.
It is a science that examines the most complex levels
of biological organizations.
Levels of Organization
Subatomic particles
Atoms
Molecules
Tissues
Organs
Organ systems
Organisms Populations
Communities
Ecosystems
Ecosphere
Earth
Planets
Solar systems
Galaxies
Universe
Subdivisions of Ecology
1.Autoecology-deals with the study of the individual
organism or an individual species. Life histories and
behavior as a means of adaptation to the
environment are usually emphasized.
2. Synecology- deals with the study of groups of
organisms which are associated together as a unit.
Subdisciplines in Ecology
Population Ecology- examines interactions that occur
between a population and its environment.
Population –is a group of individuals that belong to
the same species and inhabit a particular locale.
Species-a group of actually or potentially
interbreeding individuals.
Community Ecology-studies interactions among the
populations of all species living in an area at a
particular time, which together constitute the
community.
Ecosystem Ecology- is the study of the most inclusive
interactions, those among all the biotic and abiotic
components of the ecosystem.
Ecosystem-it includes both the community and its
physical environment.
Physiological Ecology- examines the ways that the bodily
processes of organisms are adapted to the physical
environment.
Genetic Ecology-is the study of the ways in which an
organism’s ecology shapes its heredity and the ways in
which genes influence ecological processes.
Systems Ecology-emphasizes mathematical modeling of
the interactions among the components of an ecological
system, particularly the movement of energy and
materials among the biotic and abiotic components of
an ecosystem.
Environmental Principles
1.Interdependence/Interrelatedness
Living things are interdependent with one
another and with their environment. Both the biotic
and abiotic components are equally important in
the ecosystem because the absence of one affects
the functions and existence of the others and of the
whole ecosystem.
A basic example of interdependence is the
relationship between autotrophs (plants) and
heterotrophs (animals).
2.Diversity and Stability
A diverse community is a stable community. The
more species present, the more stable the
community because several species keep other
species in check, preventing any species from
overpopulating the habitat.
3. Change
Change is basic to nature. Ecosystems change
over time and space. Any change in the community
affects the different organisms within it. Natural
change like this is healthy but human-induced
changes like environmental disturbances wreak
havoc in natural systems. These result in the
environment crises that the world faces today.
4. Balance of Nature
Ecosystems are capable of self-maintenance
and self-regulation. Predation kills offsome
members of the population and is a good
regulator of population density. Predation checks
population down to a healthy size.
5. Finiteness of Resources
Even the most abundant natural resources are in
danger of being depleted in the light of human
overpopulation and overexploitation. The fossil fuels
are in danger of running out in this century because
of too much use for industrialization and domestic
consumption by the fast growing world population.
Finiteness of Resources means that there
limitations and boundaries to utilization.
6.Pollution
Pollution is the undesirable accumulation of
substances resulting in diminished quality and utility
of a resource. Pollution is found in the air, water,
and soil and these result in several problems in the
environment, health and economy.
7. Stewardship
Christian doctrine posits that nature and its
resources are God’s gifts to all and that, when God
created the Earth, He commanded man to be His
steward.
Stewardship of resources means efficient
management by maintaining a balance between
population growth and resource use. It is not an act
of a good steward to overexploit the borrowed
resources.
8. Sustainability
Actions that address the needs of the present
without compromising the needs of the future
generations to meet their own needs are embodied in
the concept of sustainable development.
It is equally concerned with socioeconomic
development (human well-being) and environmental
quality.
A society should manage its economic growth in
such a way as to do no irreparable damage to the
environment.