Download Chapter 24 - Holy Family Regional School

Types of Interactions
Ecology: A study of the
relationship between living
things and the environment.
Individual: Organism
with unique DNA and
cells.
POPULATION: Groups
individuals who tend to
mate with each other in a
limited geographic area.
Community: The
relationships between
groups of populations.

Biome: A regional
ecosystem
characterized by
distinct types of
vegetation and
animals.
Determined by
temperature and
rainfall.
Biosphere: The part of the
earth and its atmosphere in
which living organisms exist.
The
surface of
the earth
and all the
ecosystems.
Lithosphere: Below the
surface, in the crust and
mantle.
Hydrosphere: All waters not in
atmosphere and lithosphere.
Ecosystem: The relationships
of populations with each
other and their environment.
Habitat: The type of environment
in which an organism lives.
Limiting Factors & Carrying Capacity
•Nature is varied- everything in the environment affects every other
thing.
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Population grow is controlled by limiting
factors these are scarce resources
Ex: food, water, and living space
Any resource can become a limiting factor
to a population (i.e. too many animals = too
little food)
Limiting factors cause death in
populations when they’ve get bigger
than their carrying capacity -the
largest number the environment can
support.
Limiting Factors: A factor that
causes a population to decrease
in size.
Sunlight
Water
Temperature
Disease
Parasites
Predators
Competition
Density Independent
Factors
(Non-living / Abiotic)
Density Dependent
Factors
(Other living things)
Interactions Between Organisms


Populations are contained to one species
while communities are interactions between
multiple species.
All these species within a community are
going to interact in some way. These are
the main ways species and individuals can
affect each other.
COMPETITION
PREDATOR and PREY
S YMBIOTIC RELATIONSHIPS
Competition

When 2 or more individuals or
populations try to use the same
resources
(EX: food, water, shelter, space, sunlight)


Resources are limited, so when one
animal uses them, others can’t.
Competition can happen between
animals within a population and
between different populations.
(EX: Elk compete for same plants to eat;
different plant species in a forest all want
the same sunlight)
Living things

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All living things (organisms) need food
(nourishment) to live.
Living things in an ecosystem depend on each
other for food.
Producers


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
Plants are living organisms. They need
nourishment to survive.
But…
Plants do not eat other plants or animals.
Plants are called producers, because they
make their own food inside themselves.
Consumers


“Consume” means “eat”.
Animals are consumers because they “eat”
(consume) food provided by plants or other
animals.
Herbivores
Some animals do not eat other
animals. They survive on plants
and are known as “herbivores”.
Carnivores
Some animals, like the kingfisher, eat
only other animals. These animals are
called “carnivores”.
Omnivores


Some animals, like us, eat both plants and
animals.
These animals are called “omnivores”.
Predators & Prey


Interaction where one organism eats another: prey is organism
eaten; predator is the organism doing the eating
Predators adapt in order to catch prey
(EX: cheetahs run fast; goldenrod spider blend in with flower)

Prey adapt in order to avoid predator
– Defensive chemicals can make the prey unattractive
or even poison (deadly)
– Will have warning colors that say “stay away”,
such as red, yellow, orange
– Outrun the predator or travel in groups
(schools of fish, herds of buffaloes)
– Blend in with background by either sitting still or mimicking
something non-living- this is known as camouflage
Predator
A predator eats other animals.
Cats eat fish.
So do bears!
Predator

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The cat is a predator, because it eats
other animals.
The bear is a predator, because it eats
other animals.
People are predators too!
Prey
Any animal which is hunted and killed by
another animal for food is prey.
Predator
Prey
Symbiosis A long term relationship
between two or more different
species
Parasitism: One
organism benefits while
the other is harmed.
Mutualism: Both organisms benefit.
Copyright © 2010 Ryan P. Murphy
Examples of mutualisms
Commensalism: One organism
benefits while the other doesn’t
benefit, or suffer harm.
Examples of Commensalism
The remora
just hitches a
ride to grab
some scraps
after the kill.