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ECOLOGY: LEVELS OF ORGANIZATION
ECOLOGY: LEVELS OF ORGANIZATION
WHAT IS ECOLOGY?
Ecology – the study of
the interactions of
living things with one
another and with the
environment
WHAT ARE THE LEVELS OF ORGANIZATION?
Biosphere – the portion of
earth that supports life
Where on Earth do we find
life?
Biome – a large region characterized by a specific
type of climate and certain types of plant and
animal life
Climate is determined by temperature and precipitation.
Compare our environment to:
A rain forest
A desert
The open ocean
LEVELS OF ORGANIZATION
LEVELS OF ORGANIZATION
Ecosystem – a community of organisms and
their abiotic environment
Includes living and nonliving things
ECOSYSTEMS
Biotic – the living parts of an ecosystem
Examples: animals, trees, bacteria
Abiotic – the physical or nonliving parts of an
ecosystem
Examples: sunlight, water, rocks, temperature,
sand, climate
HOW DO ORGANISMS INTERACT WITH
THE OTHER PARTS OF THE ECOSYSTEM?
What is the interaction?
Bees pollinate flowers
while getting nectar
Biotic – Biotic
Plants use solar energy,
CO2, and water to do ???
Biotic – Abiotic
KEYSTONE SPECIES – a
species that is critical to an
ecosystem because it affects
the survival and number of
many other species.
HOW DO ORGANISMS INTERACT IN A COMMUNITY?
» Sea otter eat sea urchins
» Sea urchins eat kelp.
» Kelp forests provide habitats for
fish and other aquatic
organisms.
» What happens when sea otter
are overhunted?
INVASIVE SPECIES
Plants, animals, or pathogens that are non-native to
a particular ecosystem and whose introduction
causes (or may cause) harm
Typically introduced by
humans
May not have natural
predators or diseases to
control population size
May wipe out other
populations in the
ecosystem
So, how do we fix it?
Community – a group of various species that live
in the same habitat and interact with each other
Includes only the living things
Made up of many populations
LEVELS OF ORGANIZATION
Population – a group
of organisms of the
same species that live in
a specific area and
interbreed
LEVELS OF ORGANIZATION
Organism – a living thing:
anything that has all seven
characteristics of life
LEVELS OF ORGANIZATIONMade of cells
Homeostasis
Reproduction
Heredity
Growth
Metabolism
Responsiveness
WHAT IS A HABITAT?
Habitat – the place an organism lives
Compare your habitat to:
A squirrel’s habitat
A fish’s habitat
A bacterium’s habitat
WHAT IS A NICHE?
Niche – the role an
organism has in its
environment
The sum of a species’
use of the biotic and
abiotic resources in
it’s environment
How it fits into an
ecosystem
WHAT IS A NICHE?
What does an
organism’s niche
include?
How it gets food
How finds mates
How much space it
needs
What temperature it
needs to live
Competitive Exclusion Can two species have
exactly the same niche?
To species competing
for the same
resources cannot
coexist in the same
place
The better
competitor will win
the niche and the
other species must
adjust or is
eliminated.
