Species Interaction
How Many Species Do
You Interact With Everyday?
Species Interaction
In nature, species interact all of the time.

Sometimes, their interactions can benefit both species,
other times those interactions can cause harm.

Interaction between species forms the structure of
communities and ecosystems.

Scientists use the word NICHE to describe the role each
organisms plays in an ecosystem.

A niche is impacted by tolerance - ability to survive
under changing conditions

A niche is impacted by
competition.

Niche vs. Habitat
 A species niche is
how it acts in its
environment. For
example, where it
lives, how it
interacts with
other species, and
how it moves
through each day.
 A species’ habitat is
just where it lives.
Habitats provide
organisms with all of
the resources they
need to survive. It is
simply a location.
How a species acts
inside its habitat is
part of its niche.
Ways in Which Species Interact
There are three major types of species interactions
that have been identified by scientists:
1. Competition
2. Predator-Prey Relationships
3. Symbiotic Relationships
1. Parasitism
2. Mutualism
3. Commensalism
Competition
 Competition occurs when
individuals or populations
attempt to use the same limited
resources. It can occur within
the same species or with other
species.
 Indirect competition occurs
when species don’t even come in
contact with one another.
Perhaps feeding on the same
plant in the day and the night.
 Direct competition occurs
when species invade each others
niches. The more dominant
species will prevail and have
better access to the resource.
The two bison pictured are
competing for territory, food,
and possibly a mate.
Predator – Prey Relationships
 The predator hunts and the
prey is hunted.
 Some predators only eat
certain types of prey, such
as the lynx pictured to the
right.
 Organisms have developed
adaptations to make them
better predators and/or to
enable them to hide better
from predators.
 Some of those adaptations
include camouflage,
warning coloration,
mimicry, protective
covering, etc.
The lynx is preying upon the
snowshoe hare, one of the only
things it eats. The snowshoe hare
is colored white in the winter so it
is camouflaged in the snow.
Camouflage
Watch cuttlefish video! Click Here!
Warning Coloration
Protective Covering
Mimicry
Symbiosis
•When two organisms live in close association.
•In the relationship at least one of the species benefits.
Parasitism
Mutualism
Commensalism
•Most organisms live in symbiosis with another
organism. Some may even evolve together. When that
occurs it is called co-evolution. An example of coevolution is when plants adapt to suit those insects that
pollinate them AND the pollinators adapt with the
plants.
Parasitism
 A parasite is an
A tick attached to human skin. The
tick is the parasite and the human is
the host.
organism that lives on
another organism and
feeds on it.
 The parasite gets all of
its nourishment from
its host.
 The host is generally
harmed by the
parasite.
 Examples of parasites
include ticks, fleas,
tapeworms, leeches,
and mistletoe.
Mutualism
 Mutualism is a close
Click on the picture to watch a
video example of mutualism
between ants and acacia trees.
relationship between two
species in which both
benefit.
 Humans have bacteria in
the stomach that help to
break down food that we
eat. We benefit from them
being there, and they
survive on the food we eat.
 During mutualism, each
specie depends upon the
other for survival.
Commensalism
 A relationship between
species when one organism
benefits and the other one is
neither helped or hurt.
 A great example of this
occurs between sharks and a
type of fish called a remora.
Remoras attach themselves
to sharks and feed on scraps
from the shark’s meals. They
also use the sharks as
transportation.
 Another example is when
birds nest in trees. The trees
are not hurt and they provide
a habitat for birds.