Download Population Ecology

Population Ecology ch 4ish
Population Curves
Succession
Resource partioning
Land SUCCESSION
Pond Succession
One thing leads to another
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What is succession?
What is a climax community?
What are pioneer plants?
What is primary succession?
What is secondary succession?
SUCCESSION
• The replacement of
one community by
another
PIONEER PLANTS
• The first plants to appear in a community
• For example, lichens are often the first
plants to appear on bare rock
PRIMARY vs. SECONDARY
SUCCESSION
PRIMARY
SUCCESSION/ BARE
SECONDARY
SUCCESSION:
ROCK SUCCESSION: • Growth on land where
there has been
• Succession on land
previous growth, such
where there was no
as abandoned fields or
previous growth
forest clearings
Succession
Climax Community : Last stable
stage of succession.
Succession to a climax community
Puffer protection
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pufferfish.flv
antlion death trap.flv
antlion anatomy.flv
Peacock spider
How Ecosystems change
Ecology Population
• Biotic potential -The
maximum
reproductive rate and
all live and
reproduced
Lemmings migration
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Rat population
Rabbit can multiply
POPULATION ECOLOGY
Over reproduction (Biotic potential)
Over reproduction (Biotic potential)
Over reproduction (Biotic potential)
Over reproduction (Biotic potential)
Over reproduction (Biotic potential)
Biotic Potential
• maximum rate at which a population could grow
given optimal conditions (food, water, space)
• Factors that influence biotic potential:
(Environmental Resistance)
• 1. age of reproduction
2. frequency of reproduction
3. number of offspring produced
4. reproductive life span
5. average death rate under ideal conditions
Environmental Resistance:
• Factors that Decrease the birth rate, or
increase death rate, related to
environmental conditions, such as food &
space.
• Density Independent Factors: weather
and other natural disasters
• Density Dependent Factors: food, space,
water, parasitism, competition
Ecology Population
• Environmental resistance –factors that reduce
population growth rates –disease, predation,
weather…
• dragonfly1.flv
Ecology Population
• Carrying capacity –
the maximum number
of individuals of a
population an area
can support in terms
of food, space and
shelters.
• Birth – death = pop.
Population Growth
When is population growth zero?
G=growth
r= rate of reproduction
N= number of individuals
K=carrying Capacity
r-selection=Reproduction/short life cycle ; no
parental care
k selection = low offspring production,
parental care
R Unstable environment, density
independent
small size of organism
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K Stable environment, density
dependent interactions
large size of organism
energy used to make each individual is low energy used to make each individual is high
many offspring are produced
few offspring are produced
early maturity
late maturity, often after a prolonged period
of parental care
short life expectancy
long life expectancy
each individual reproduces only once
individuals can reproduce more than once
in their lifetime
type III survivorship pattern
type I or II survivorship pattern
in which most of the individuals die within a
in which most individuals live to near the
short time
maximum life span
but a few live much longer
Carrying Capacity- The maximum
number of individuals and area can support in
terms of resources
Population Graph
What is happening in phase A?
What is happening in phase B?
Human population Growth
Human Population based on a
Fossil Fuel Economy
Predator / Prey Populations
The Abiotic factors affect
populations
Rabbit Myxoma virus
Habitat Formation
• A) Competition
– Intraspecific -same species
– Interspecific - different species
• B) Coevolution -two or more
species ‘evolve’ in response to
each other (insects & flowers)
• Predator/Prey relationships
– Plant defenses
– Animal defenses
– Animal deceptions –mimicry
• ‘Way of life” in a
Niche
specific habitat
• COMPETITIVE
EXCLUSION
PRINCIPLE
• Niche overlap
increases competition
and leads to a
‘realized niche’ –area
that the organism
actually occupies
Kangaroo Island
Koala activity
• koala over population.flv