Transcript A Population

Species
Populations
Limiting factors
Communities
Habitats
Niches
Cooperation
Competition
Symbiosis
Ecology
Textbook
Sections
2.1 and 2.2
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O Science
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Species
• Scientists group living
things according to their
shared characteristics
Yellow-sided
• The smallest grouping Cinnamon
Green Cheeks Green Cheek
is a species
• Scientists consider organisms to be
members of the same species if the
organisms are so similar that they can
successfully reproduce
Population
• A group of
species that live
in a particular
bounded area
is a population.
• In ecology, members of the
same species that live in a
different area belong to a
different population
What is a large
group of species
in a bounded
area?
A
Population
Factors Affecting Populations
For any population to thrive, there must be
enough food, water, light and living space.
These factors are known as limiting factors.
Limiting factors determine how many
organisms can live in an environment.
An environment contains only limited amounts of
water, food, or living space. When any of these
factors becomes scarce it can affect population
size.
Name the four
limiting factors that
affect populations
Food
Water
Light
Living space
How Limiting Factors Affect A
Population
Food
Plants make their own
food. All other organisms
obtain food and energy by
eating other organisms.
Food is a limiting factor
because only so much is
available in an ecosystem.
Water
The cells and tissues of
plants and animals are
made primarily out of
water.
All living organisms need
water to move materials
throughout their body’s
tissues and cells.
Light
Plants and other organisms
that make their own food
need sunlight to carry out
photosynthesis.
If light is limited, the growth
of these organisms will also
be limited.
Living space
Organisms need
space to live,
reproduce and
obtain resources.
The place where an organism lives is called it’s
habitat.
Carrying
Capacity
The largest population
that an environment can
support over a long
period of time is known
as the environment’s
carrying capacity.
What is the largest
population that an
environment can
support over a long
period of time
Carrying
Capacity
When a population grows larger
than its carrying capacity,
limiting factors cause the
population to get smaller.
Example- Drought
= decreased plant production
= decreased food supply
= increased starvation
Habitat
• The natural environment in
which a living thing gets all the it
needs to live is called it’s habitat.
• Habitat is the physical location
where plants and animals live
• A habitat is filled with many
different species.
Future Natural Habitat for Man
What is the physical
location where plants and
animals live known as?
A
Habitat
Niche
• The role that each organism
plays in a habitat is referred to as
its niche.
• The niche an organism fills in a
habitat is not limited to its place in
the Food Web.
• Generally no two species have
the same niche
Niche Examples
• Trees may be seen
as a producer of leaves
that the caterpillar
consumes.
• Trees may also provide
a nest for birds or other
animals or insects
Community
A group of populations that live in a
particular area and interact with one
another are called a community.
Populations of frogs, fish, cattails, and
snakes live in a pond community
What is the difference
between a
community and a
population?
A population is a large group
of species that live in a
particular area
A community is a variety of
populations that live and
interact together in a
particular area
The Environment can be
organized into five levels
1. Organism- a single living thing
2. Population- a group of organisms of the
same species that live in the same area
3. Community- made up of the living
components of the ecosystem
4. Ecosystem- living and non-living factors
interact to form a stable system
5. Biome- similar climate, plants, and animals
throughout an area
Name the five levels
of an environment
1. Organism
2. Population
3. Community
4. Ecosystem
5. Biome
Cooperation
• Sometimes organisms work
together in a way that benefits the
whole group
• Killer whales hunt in packs known
as Pods
• Lions live in family groups called
prides in which members
hunt in teams and share
the kill with everyone
Interactions and Relationships
Among Organisms
The relationships and interactions that
species form in an ecosystem can be
divided into these three categories.
Competition
Predation
Symbiosis
Competition
Competition occurs when two or more individuals or
populations try to use the same limited resource such as
food, water, shelter, space or sunlight.
Examples:
Two herbivores competing for the same plants.
Different species of trees competing with each
other for sunlight and space
Competition may occur within species or between species.
Only those organisms able to get the resources they need will
survive.
Predation
Predation is a type of feeding relationship in which one animal
captures and eats another animal for food.
The animal that is eaten is the
prey.
The animal eating the prey is the
predator.
Predator-prey relationships help to keep an ecosystem in balance
by preventing any one population from getting too large.
Symbiosis
A close, long-term association between two or more
species is called Symbiosis.
The individuals in a symbiotic relationship can
benefit from, be affected by, or be harmed by the
relationship.
Often one species in a
symbiotic relationship lives
in, on, or near the other
species.
Symbiotic relationships that occur in
nature are classified into of these three
groups:
Mutualism
Commensalism
Parasitism
Mutualism
Mutualism is a relationship in which both species
benefit.
Example
Pollination
A relationship between
flowers and insects
A flower provides a food reward to an insect in the form
of nectar (a sugar rich solution). If the food reward is
large enough, the insect is likely to go looking for flowers
of the same plant species after it is done visiting the first
flower. The flower species then gets its pollen passed on
to another plant so that it can reproduce.
Commensalism
Commensalism is a type of symbiosis in which
one species benefits while the other seems to be
unaffected.
Example
The clown fish and the sea
anemone
The clown fish lives among the deadly tentacles of a sea anemone.
The anemone's tentacles contains nematocyst, which paralyzes the
anemone's prey and protect it against predators. Yet the clown fish is
not stunned. Living within the anemone's tentacles, the clown fish
gains protection, as well as food from leftovers of the anemone's
meals.
Parasitism
Parasitism is a symbiotic association in which one
organism benefits while the other organism is harmed.
The organism that benefits is called a parasite. The
organism that is harmed is called the host.
The parasite gets nourishment from the host. The host in
turn is weakened and may die.
Some parasites live outside the hosts body.
Example: ticks or fleas
Other types of parasites live inside the host’s body:
Example: tapeworms
Name and describe
three symbiotic
relationships in
nature.
The
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