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Habitats, Environment &
survival
Habitat
• Where does an animal live, where can I
find it?
• What is there address?
• The habitat in which they live.
• If I am searching for a koala I do not go to
an open grassed field, but to a eucalypt
forest of certain species
Habitat
• Unlike you and I, an animal needs to get all its
requirements for living from the area in which they live.
• They need, light, water, food, shelter, mates, other
associated animals etc.
• The place that provide this for an animal is known as its
habitat.
• How many different types of habitat can you think of?
Micro Habitats
• An animals habitat can be described in more
detail as a microhabitat.
• In a eucalypt forest there are hundreds of
organisms but they don’t all live in the same
spot.
• A spiders microhabitat may be under the bark, a
koala in the trees near new leaves, etc
• What microhabitats exist in a reef environment?
Community
• All the people in our neighbourhood are
known as the community.
• All the organisms, plant and animals are
known as the community of an ecosystem.
• What is an Ecosystem?
An ecosystem
• An ecosystem is made up of both living
and non living parts that interact with each
other.
• Make a list of the non living parts, the
living parts, interactions that may occur.
Energy in Ecosystems
Ecosystem
Biotic factors
(Living)
Abiotic factors
(Non-living)
Interactions
between
Biotic &
Abiotic factors
Biotic
• Biotic factors are living things.
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They include all living organisms
They may affect an ecosystem through provision of
Food
Energy
Nutrients
Shelter
Predators
Prey
Parasites
Abiotic
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Abiotic are all non living components of an ecosystem
Soil
Air
Temperature
Water
pH
Light intensity
Slope
Aspect
Topography
Rocks
Salt
Minerals etc
Interactions
• Light  Plant  Photosynthesis, energy
conversion
• Plant  Animals, path of energy flow
• Light  Temperature
• Water  Animals  Water
• Light  Animal life
Range/Distribution
• Where a species of animals is found is known as it’s
range.
• It can be large or small, this has no affect on density of
population
• A range may be densely or sparsely populated.
• The range of the cane toad is expanding, to the
detriment of the environment.
• Can you think of an animal whose range is decreasing?
Range
• Fox Range
• Rabbit Range
Range/Distribution Limitations
A number of factors can limit the range of an
organism.
1. Abiotic factors – the environment
2. Geography - barriers
3. Biotic factors – competition & predation
Environmental abiotic Factors
Environmental abiotic factors can limit range
distribution
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Not hot enough
Too much salt
Not enough light
Not enough water etc
Tolerance Range
• The tolerance range of an organism
indicates what abiotic conditions they can
survive in.
• Eg light, temperature, rain fall, pH,
turbidity, oxygen, UV light, salt etc
Tolerance range
• An organism has an optimal tolerance range in
which they survive and reproduce easily.
• A zone of stress, in which they can survive but in
poor condition and not necessarily reproduce.
• A zone of intolerance where they cannot survive
at all.
• The wider their optimal range of tolerance the
larger there range is likely to be.
Tolerance Range
• Some animals have huge tolerance
ranges being able to survive and
reproduce in a large range of
environments.
• Whilst others have very small tolerance
ranges and can only survive in very
specific areas. These are the species that
are most endanger from human impact.
Law of Tolerances
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If an organism is outside or on the cusp
of it’s tolerance range it has two choices
1. Stay and die
2. Migrate and flee
Migration
• Animals ranges can increase, spread and
move through the migration of the
population.
• Some animals have a migratory pattern
(whales) and others just follow food or
inhabit suitable areas as they are provided
(locusts and insects)
Geographic Barriers
• Geographic Barriers also limit range distribution.
• There are no foxes in Tasmania (as yet
confirmed), they cannot cross the sea.
• Geographic barriers can also include things
such as large mountains, snow and lava fields.
• Can you think of any other animals that have
been restricted geographically?
Niche
• Where have you heard the word niche
before?
• Niche means way of life or the role of an
organism.
• Each species has its own niche, they eat,
live, reproduce their own way.
Niche competition
• A niche describes everything about the
way an organism lives – place, food
source, time of activity, reproductive
areas, watering holes etc.
• If two organisms exist in a community with
the same niche what would happen?
Competition : Niche Overlap
• When a niche overlap occurs these two species
are in competition for a resource.
• The resources might be shelter, food, or mating
spot.
• The main point is two into one cannot go, so
eventually one species must lose out.
• This can affect their range, if there is already an
organism that fills their ‘niche’.
Ecological Niche
• Lets learn about ecological niches and
ways to overcome competition.
Law of Tolerances
• Investigate the law of tolerances and the
effect of niche overlap on the population of
organisms.