Download Relationships in Ecosystems

Relationships in
Ecosystems
Vocabulary
Relationships in Ecosystems
Big Ideas
Diversity and Evolution of Living Organisms
 Explore the scientific theory of evolution by
relating how the inability of a species to adapt
within a changing environment may contribute
to the extinction of that species.
 Discuss distinguishing characteristics of the
domains and kingdoms of living organisms.
Relationships in Ecosystems
Big Ideas
Interdependence
 Explain and illustrate the roles of and relationships
among producers, consumers, and decomposers in
the process of energy transfer in a food web.
 Compare and contrast the relationships among
organisms such as mutualism, predation, parasitism,
competition, and commensalism.
 Describe and investigate various limiting factors in
the local ecosystem and their impact on native
populations, including food, shelter, water, space,
disease, parasitism, predation, and nesting sites.
Relationships in Ecosystems
Big Ideas
Interdependence
 Compare and contrast the relationships among
organisms, including predation, parasitism,
competition, commensalism, and mutualism.
 Use a food web to identify and distinguish
producers, consumers, and decomposers.
Explain the pathway of energy transfer through
trophic levels and the reduction of available
energy at successive trophic levels.
Relationships in Ecosystems
What is an organism?
 An individual living thing
What is an environment?
 The place where an organism lives (its habitat)
What does an organism get from its environment?
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Food
Water
Shelter
Other things it needs to live, grow and reproduce
What is a niche
 The role an organism plays in its habitat
Interactions Among Living Things
Niches
Organisms occupy many niches in an environment.
Relationships in Ecosystems
What are the two parts of an organisms’ habitat?
 Biotic factors
 Living or once living
 Examples: Living organisms, decomposing plant
material, owl pellets
 Abiotic factors
 Nonliving factors
 Examples: sunlight, temperature, water
Relationships in Ecosystems
 Some abiotic factors
 Air 78 % nitrogen, 21 % oxygen and .04% carbon dioxide
 Water is a major ingredient of the fluid inside the cells of all
organisms.
 Soil is a mixture of mineral and rock particles, the remains of
dead organisms, water, and air. The decaying matter found in
soil is called humus.
 Sunlight is the energy source for almost all life on Earth.
 Temperature of a region depends in part on the amount of
sunlight it receives, as well as the latitude and elevation
 Climate refers to an area’s average weather conditions over
time, including temperature, rainfall or other precipitation, and
wind
 Wind –motion of air from its heating by the Sun creates air
currents that are called wind.
Living Things and the Environment
Factors in
a Prairie
Habitat
A prairie
dog interacts
with many biotic
and abiotic
factors in the
prairie habitat.
Relationships in Ecosystems
How is an ecosystem organized?
 Organisms – living things
 Species – organisms that can mate with each other and
produce offspring that can also mate and reproduce
 Population – All members of one species in a particular
area
 Community – All the different populations in a particular
area
 Ecosystem – All of the communities in a particular area
 Biosphere – All of the ecosystems on Earth
Draw concentric circles showing the organization of the biosphere
Living Things and the Environment
Ecological Organization
The smallest level of organization is the organism. The largest is the
entire ecosystem.
Relationships in Ecosystems
What is ecology?
 The study of how organisms interact with each other and
with their environment
Energy Flow in Living
Organisms
 A food chain shows a sequence of organisms
that eat other organisms.
Energy Flow in Living
Organisms
 As you can see, organisms that make their own food are
called autotrophs or producers
 Organisms that eat other organisms are called
heterotrophs or consumers. Three types:
 Herbivores – eat only producers
 Omnivores – eat producers and other consumers
 Carnivores – eat only other consumers
 The first heterotroph in a food chain is called the primary
consumer, the second, secondary; the third, tertiary
 Organisms that break down dead organisms are called
decomposers (detrivores)
Energy Flow in Living
Organisms
 On a page in your notes, draw a food chain.
Include a producer, primary, secondary and
tertiary consumers and a decomposer.
Remember that decomposers return nutrients to
producers
Energy Flow in Living
Organisms
 For the purposes of energy flow, a food chain
(web) involves the transfer of energy from one
organism to another through the cycling of
matter (food)
Energy Flow in Living
Organisms
 As you move up a food chain, energy is
converted when organisms higher up eat
organisms lower down.
 Some energy is lost during each conversion
(Second Law of Thermodynamics); organisms
higher in the food chain receive only part of the
energy from the organisms they eat.
 The energy efficiency of each new level in the
food chain is 10% of the level below it.
Energy Flow in Living
Organisms
 Because of this loss of energy as organisms eat
other organisms, as you move up a food chain,
there are fewer and fewer organisms
Relationships in Ecosystems
Energy Flow in Ecosystems
 Energy Pyramid
 Trophic levels
 Primary
 Secondary
 Tertiary
Energy Flow in Ecosystems
Energy Pyramids
Suppose that the producers at the base of an energy pyramid contain
330,000 kilocalories. How much energy would be available at each level of
the pyramid?
Energy Flow in Ecosystems
Food Web
A food web consists
of many
interconnected
food chains.
Energy Flow in Living
Organisms
 In a food web, lines with
arrows are drawn between the
organisms being eaten and
the organism eating it
 The arrow always points from
the predator toward the
prey, because this is the
direction of the energy flow
Relationships in Ecosystems
Adaptations can cause special relationships to occur
between different species
Common relationships exist between organisms
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Predator/prey
 One organism (predator) eats another (prey)
 Predator adaptations
 Running fast
 Hunting at night
 Prey adaptations
 Mimicry
 Camouflage
 Predator/prey populations
 An increase in predators may lead to a decrease in prey, which leads
to a decrease in predators and an increase in prey
 Adaptations may cause escalation
 Faster cheetah selects for faster gembock
Interactions Among Living Things
Predator-Prey Interactions
On Isle Royale, an island in Lake Superior, the populations of wolves
(the predator) and moose (the prey) rise and fall in cycles.
Relationships in Ecosystems
Adaptations can cause special relationships to occur
between different species
Common relationships exist between organisms
 Competition
 organisms compete for food or other resources in the
same habitat
 Adaptations may reduce competition
 Living in different parts of a tree
 Feeding at different times of day
Relationships in Ecosystems
Adaptations can cause special relationships to occur
between different species
Symbiotic relationships exist between organisms
At least one organism must benefit
 Parasitism
 Parasites live on (head louse)/in (tapeworm) another animal (host) and
feeds on it (parasite benefits at expense of host)
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Commensalism
 animals benefit from each other (hermit crabs with sea anemones on
its shell)
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Mutualism
 animals depend on each other (termites and protozoans that live in
their intestines, coral polyps and zooanthellae)
Populations
 Populations change in size
 Births and deaths
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Birth rate – number of births in a certain time period
Death rate – number of deaths in a certain time period
If birth rate > death rate, population size increases
If birth rate < death rate, population size decreases
 Growth rate = birth rate – death rate
Populations
 Immigration and emigration
 Immigration – organisms moving into an area
 Emigration - organisms moving out of an area
 Population density
 Number of individuals / unit area
 Example: 20 butterflies in a 10 m2 garden
 20/10 = 2 butterflies / m2
Populations
Immigration/Emigration in a Rabbit Population
This graph shows how the size of a rabbit population changed over
ten years.
Populations
Population Density of the Flamingos in the Pond
In the pond on the top, there are 10 flamingos in 8 square meters.
The population density is 1.25 flamingos per square meter.
Populations
 Limiting factor
 Environmental factor that causes a population to stop growing or
decrease in size
 Largest population an area can support is its carrying capacity
 Factors that limit population growth
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Food
Shelter
Water
Space
Disease
Predation and Parasitism
Nesting sites
Populations
 Factors that limit population growth in the
Everglades
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Water Flow
Pesticides and Herbicides
Invasive species (example: Burmese python)
Urbanization
Water and air quality
 Food
Classwork 1
Copy the questions into your notebook and answer them
1.
2.
3.
1.
5.
Name three things an organism gets from its
environment
___ factors are living or were once living; ___ factors
are non-living
Place these in order from smallest to largest:
Population Organisms Ecosystem Community Species
Name the type of relationship:
a. animals benefit from each other
b. animals depend on each other
c. organisms compete for food or other resources in same
niche
d. One organism eats another
e. One organism lives on/in another
List four factors that limit population growth
Classwork 1
Copy the questions into your notebook and answer them
1.
2.
1.
2.
Identify the type of organism
a. break down dead organisms
b. eat only other consumers
c. eat only producers
d. make their own food
e. eat producers and other consumers
Part of a food chain: Organism A  Organism B
Which is the predator?
In a population, the birth rate is less than the death rate. Is the
population increasing or decreasing?
As you move up a food chain, energy is converted when
organisms higher up eat organisms lower down, but the energy
efficiency of each new level in the food chain is 10% of the level
below it. How does this affect the number of organisms as you
move along?
Classwork 1
Copy the questions into your notebook and answer them
10. Name three factors that limit populations in the Everglades