Transcript Ecology of Organisms - Nutley Public Schools

ECOLOGY
Reference Modern Biology
Chapter 19 - 23
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Words to Know
ecosystem
community
population
habitat
adaptation
trophic level
energy pyramid
biodiversity
food chain
biome
ecology
niche
symbiosis
food web
producer
decomposer
nitrification
biomagnification
biotic
abiotic
consumer
succession
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Big Idea
Interdependence of Organisms
– All organisms affect and are affected
by living and non-living components of
their environment.
Click on the
picture to
view a short
video
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Assessing Prior Knowledge
How might a constantly changing
environment affect natural
selection?
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What is Ecology?
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All the organisms in an ecosystem relate to
all the other living parts, as well as all the
non-living parts of the ecosystem…
They have a relationship…
The study of this relationship between
organisms and the living and non-living things of
their environment is called Ecology.
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WHAT IS AN ENVIRONMENT?
An environment is the collection of all the
animals and plants in a specific area of land
or water. Each environment has its own
characteristics such as climate, soil or water
content, and plant and animal life.
Some examples of environments are wetlands,
deserts, grasslands, forests, and large bodies
of water.
Urban Environment
Dessert Environment
Polar Environment
Salt-Water
Environment
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ECOLOGISTS
Biologists who study ecology - that is, populations,
communities, and ecosystems - are called ecologists.
They gather information by conducting fieldwork –
studying living things in their natural habitats.
The information can be used, for example, to
determine an animal's population size, diet,
territorial boundaries, and behavioral patterns.
Fieldwork also includes the study of the physical
factors in the environment, such as the soil, rocks, air,
In addition to embarking on many
and water.
research trips, ecologist Andy
Dobson travels with alumni to
share his expertise. While leading
an alumni trip to the Peruvian
Amazon, he had a close encounter
with this baby tapir, an animal
indigenous to the region. (photo:
Peter Hudson)
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ECOLOGISTS
FYI: One aspect of fieldwork is sampling a population
of organisms. The technique of sampling uses a
representative portion of a population to determine
one particular characteristic of the entire
population.
Crab Sampling Stream Sampling
Marine Life
Sampling
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ECOLOGICAL MODELS
FYI: Because ecosystems are complex and often
difficult to study, Ecological Models are often used
to help them understand the environment make
predictions about how the environment might change.
Effect of Climate
Change & Disease
Global Temperature
Change
Predicting Ozone Change
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Why is it important to study Ecology?
Studying Ecology will help you understand
how natural phenomena (not a man-made event)
and human activity can affect the balance
of natural cycles and alter the living world
within an ecosystem…
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Why is it important to study Ecology?
Over the past few decades, humans have
altered the environment on a greater
scale than ever before…
Learning how to improve our effect on the
environment is critical to our survival…
Exploding Human Population
Mass Extinction
Thinning Ozone
Layer
Climate Change
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Today’s Environment
http://www.worldometers.info/worldpopulation/
Click on the Link Above to Access the “World
Populations Clock” – How many people lived on
earth in 1930? Today?
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Levels of Organization
To understand the environment better,
Ecologists organize the environment into
hierarchy of levels, each with unique
properties.
1. Biosphere
2. Biome
3. Ecosystem
4. Community
5. Population
6. Individual Organism
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Levels of Organization
Biosphere: thin layer of earth and its
atmosphere in which life exists (all the places
life can be found around earth).
In other words, a biosphere is the sum of all the
ecosystems established on Earth.
•It is about 13 miles thick
•Extends from 6 miles above the earth’s
surface to deepest parts of the ocean.
•Includes:
•Atmosphere-air
•Lithosphere-land
•Hydrosphere-water
**Most organisms are found very close to
the surface of land or water.
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BIOSPHERE
Levels of Organization
Biomes:
Ecologists divide the biosphere into
large areas called biomes.
Biomes are areas of land or water that have similar
weather conditions.
Some examples of biomes are oceans, forests,
grasslands, tundras, and deserts.
Biomes are made of
similar smaller units
called
Ecosystems
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Levels of Organization
Ecosystems:
Ecosystems are all of the living organisms (biotic)
interacting with their non-living (abiotic)
environment in a particular place.
Every organism in an ecosystem interacts with, and
needs each component (living & non-living) for its
survival.
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Levels of Organization
FYI: An ocean ecosystem includes fish, mammals,
plants, and algae. It also includes the materials
that make up the ocean floor, rocks, salt water,
the temperature, availability of sunlight and much
more.
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Levels of Organization
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Levels of Organization
FYI: The size of ecosystems varies
tremendously. An ecosystem could be an
entire rain forest, or it could be a puddle or
a backyard garden. Even the body of an
animal could be considered an ecosystem,
since it is home to numerous microorganisms.
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For example, this picture
shows a small, decaying
tree trunk ecosystem
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This pond is an ecosystem.
This forest is an ecosystem.
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Levels of Organization
The open ocean and the
rocky shore line are
both ecosystems.
Different organisms live
in each ecosystem.
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Levels of Organization
All ecosystems fall into 2 categories:
1. Terrestrial (land)- forest, desert..
2. Aquatic (water)-lake, marsh, ocean..
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Levels of Organization
Community:
This includes all the populations
of organisms of different species living in a
specific geographic area at one time.
In the diagram below, note how populations of
gold fishes, salmons, crabs and herrings coexist
in a specfic location. A thriving community
usually includes great biodiversity.
Biodiversity is the
variety of life.
Let’s look at the
species biodiversity
within a local pond.
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Levels of Organization
Populations:
A group of individuals of a
given species that lives in a specific geographic
area at a given time is called a population.
Populations include individuals of the same
species that can breed together.
Example:
A group of the same
type of sea otter
that all live in the
same place is called a
population of sea
otters.
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FYI: There are many different populations in
any given community. In an ocean community,
there might be many populations of fish. There
may also be a population of sea otters, and a
population of sea turtles all living together in the
same ecosystem.
No population
ever lives alone.
All populations
interact with
each other in a
given
community.
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Levels of Organization
Individuals, species, organisms:
The
simplest level of organization in ecology is that
of the individual organism or species.
Individuals do not breed with individuals from
other groups or species.
Animals, unlike plants, tend to be very definite
with this definition because some plants can
cross-breed with other fertile plants.
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Levels of Organization in an
Ecosystem
A Key Theme in Ecology
The key theme of Ecology
is interconnectedness.
No organism is isolated.
To survive, an organism
interacts with its
environment to maintain
biological stability and to
survive.
Credit: Wikimedia Commons
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ECOLOGY OF ORGANISMS
Environmental factors that influence an
organisms ability maintain biological
stability and survive include:
**BIOTIC FACTORS – living parts
**ABIOTIC FACTORS – nonliving parts
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Biotic factors - The living parts of an
environment.
For a fish in the aquarium, the biotic factors
could include other fish, snails, algae, and
plants.
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Components that involve non-living things are
known as abiotic.
For that same fish, the abiotic factors could
include the water, air bubbles, gravel, water
acidity and salinity, temperature, wind, and
the sunlight amount.
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So, all the biotic as well as the
abiotic factors influence an
organism ability maintain biological
stability and survive AND
contribute to a balanced ecosystem.
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Abiotic or Biotic?
Abiotic
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Abiotic or Biotic?
Biotic
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Ecology of Organisms
Ecosystems, when left alone, are usually balanced.
Ecosystems stay in balance because organisms
respond to their environment.
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Ecology of Organisms
Organisms respond to changes in their
environment:
•Immediate response/migration-leave the area
•Acclimation-adjust their tolerance to abiotic factors over
time.
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Ecology of Organisms
•Control Internal Conditions-
•Conformers: do not regulate their internal conditions – they change
as their environment changes (“cold-blooded”, ectotherms).
•Regulators: use energy to keep control of their internal conditionsdon’t change as environment changes (“warm-blooded”; endotherms)
•Dormancy/Hibernation-reduced activity during unfavorable
conditions.
•Adaptation-a trait that gives an organism an advantage for
survival, inherited. The “adaptation” appropriate to the
environment may change over time for a species – evolution.
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Ecology of Organisms
To understand an organism's relationship to its
environment we must know its role in its
environment.
A species “NICHE” is its role the species play in
the environment.
The niche may include:
• Its “habitat” or where it lives
• the range of conditions the species can
tolerate
• What it eats
• Needed resources
• Behaviors - When it sleeps, hunts,
reproduces, etc.
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Ecology of Organisms
Every organism in an ecosystem has a
place to live, called a habitat.
The ocean or lake is the habitat of sea
turtles.
The habitat of a bullfrog is a
pond.
The habitat of a giant anteater
is open grassland.
An organism's habitat is its
"address” or home.
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Ecology of Organisms
For example, a spider’s NICHE includes its
habitat (web) and its job of eating insects.
This helps the ecosystem stay in balance by
keeping the insect population down.
**Only one niche can be occupied by only one
species.
**When 2 or more species overlap, the species
will compete to get what they need.
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FYI ~
If two different species of birds ate the same
species of insects from treetops in the same forest,
there would be competition between them. In this
case, the competition between the two bird species
would be intense because of the overlap in their
niches.
However, if the two bird species fed on different
insects in the same treetops-or on the same
insects but in different parts of the trees-there
would be less overlap in their niches and reduced
competition between them.
The greatest competition usually occurs between
members of the same species, because such
individuals are more likely to share identical
niches.
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GENERALISTS - species
with a broad niche; tolerate
a range of conditions and use
a variety of resources.
Example-Virginia opossum
(found across the U.S).
SPECIALISTS - species
with a narrow, specified
niche.
Example-koala (Australia)
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Organisms can come in and disrupt niches…
•Introduced species
•Invasive species
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Introduced Species:
A species brought into an area either on
purpose or accidentally, that did not
originally live in that area.
Disrupts relationships in ecosystems where
each species has a well-defined niche; the
new species usually has little competition.
•Can become widespread.
•Can cause decline or destruction of some
naturally occurring species.
•Ex: Zebra mussels, “killer” bees,
Dandelions, Cane toads
Invasive species: Species that overtakes
the others around it; there are no species
to slow its growth.
•Major issue to ecosystems
•Ex:
•Purple Loosestrife- introduced in
1860s; chokes waterways and
wetlands in northern states.
•Kudzu-introduced to control
erosion along highways…grows so
fast (1 foot per day) it cover trees,
houses, telephone poles.
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POPULATIONS
Ecologists are more interested in groups of
organisms than individuals.
In large part, the study of ecology is about
populations and communities and the factors
that influence them.
Thus, an important area in Ecology is the
study of population growth.
.
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POPULATIONS
REMEMBER: A population is a group of
organisms that belong to same species
and live in a place at the same time.
Some factors that influence populations
include:
•Size – number of individuals in an
given area
•Density – how crowded that area is
•Dispersion – how scattered are the
individuals in that area
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POPULATIONS
Population Size - number of individuals
that make up a population
•Population size changes over time.
•If the birth rate is higher than death
rate = population increases.
•If the death rate is higher than birth
rate = population decreases.
•If more individuals move into the area
(immigration) than leave the area
(emigration) = population decreases and
visa versa.
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POPULATIONS
Population size cannot increase forever.
All populations are limited by their environment.
The limiting factors of an ecosystem prevent a
population from growing beyond a certain size.
LIMITING FACTOR - something that prevents
a population from growing beyond the carrying
capacity.
Examples - resources (water, food,
shelter, etc) and space.
Some factors affect the population equally no
matter what size the population is.
Examples - natural disasters (fire, flood)
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LIMITING FACTORS
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POPULATIONS
CARRYING CAPACITY - the maximum number
of individuals of a population an ecosystem can
support and maintain.
Every ecosystem has different carrying
capacity.
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FYI ~ Limiting Factors & Carrying
Capacity
Limiting factors are very closely tied to carrying
capacity. Many kinds of animals can increase in
numbers very quickly, and may temporarily exceed
the carrying capacity of their habitat. This
results in stress, starvation, disease, predation
and parasites, poor reproductive success and
damage to the habitat. For example, multiplying
muskrats can very quickly eat all the vegetation in
a marsh. With the vegetation gone, food becomes
the limiting factor and the muskrats may starve
or move to another area. The marsh now has a
reduced carrying capacity for muskrats until the
vegetation grows back again.
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Population graphs can be used to show how
two populations are related to one another.
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POPULATIONS
Population Density - how many individuals in a
population are in a given area.
•Example- number of trees in a square meter
of forest. 54 trees/m2
Population Dispersion - how the population is
spread out.
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FYI ~ Carrying Capacity for Humans ~
What is the Earth’s carrying capacity for humans?
Some ecologists believe that the population is
already past Earth’s carrying capacity and that
serious environmental problems have already
begun such as:
•Inadequate freshwater supply and other
resources
•Forced extinction of vast number of species (lost
of habitat)
•Industrialization (increases pollution)
What is clear is that the human population, like
any other organism can not continue to grow.
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Polluted soil, air and water; lack of food and
space; and widespread disease may ultimately limit
human population size.
However, people can make wise choices because
we do have an environmental responsibility …….
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