Introduction to
Ecology Notes
What is Ecology?
Ecology is the study of interactions that take place between organisms and their environment.
Why do we study Ecology?
By understanding the relationships in the ecosystems, we can:
– Help struggling populations rebound.
– Prevent species from dying out.
– Understand how we (humans) impact the environment.
An Organisms Environment
Abiotic Factors: all the non-living things
that make up an organism’s environment
Includes physical factors such as: Water,
soil, light, and temperature
Biotic Factors: all the living things that make
up an organism’s environment
Includes living factors such as: Plants and
animals
Organization in the Environment
•There are a lot of factors which make up an organisms environment. To avoid confusion;
Ecologists organize the environment with different levels.
1) Organism- any living thing (one individual)
2) Population- group of organisms of the
same species in an area
3) Community- made up of all the populations
of different species
4) Ecosystem- made up of a community of
organisms and its abiotic factors
5) Biosphere- part of the Earth where life
exists
Living Things Need Energy
Consumer- organism that needs to get
Producers- organisms that gets energy
its energy from another source.
by making its own food.
Decomposers- organism that gets energy by
breaking down the remains of dead
organisms.
Energy Pyramid
Types of Consumers
There are several types of consumers:
Herbivores, Carnivores, Omnivores, Scavengers
1) Herbivore- organism that eats plants only.
ex: grasshopper, prairie dogs, deer
2) Carnivore- organisms that eats meat only.
ex: coyotes, hawks, owls
3) Omnivore- organism that eats both plants and meat.
ex: mouse, human
4) Scavenger- organism that feeds on the body of dead animals
ex: turkey vulture
Food Chains:
•Food Chains- diagram which represents
how the energy is moved from one
organisms to the next.
Usually 3 – 5 organisms long
Food Webs:
•Food Webs- shows all the possible
pathways of energy in an ecosystem
•Consists of two or more food chains
Remember the  (arrows) represent
the flow and direction of ENERGY