Download Niche & Community Interactions PPT

I. Niche

Describes
what
an
organism does and how
it interacts with the
biotic
and
abiotic
factors
of
its
environment.
Niche

Resources refer to any
necessity of life, such as
water, nutrients, food,
or space.
Niche


The Physical Aspects of
the Niche are the abiotic
factors that are required for
survival. An example would
be water.
The Biological Aspects of
the Niche involve the biotic
factors that are required for
survival. An example would
reproduction and food.
Niche

There are two conditions that help define where and
how organisms live.
 Tolerance
 Is the ability to survive and reproduce under a
range of environmental conditions.
 All organisms have an upper and lower limit of
tolerance for every environmental factor.
 Habitat
 Is the general place where an organism lives.
Competition


Occurs
when
organisms attempt to
use the same limited
ecological resource
in the same place and
time.
Can be intraspecific
or interspecific.
Competition

Competitive
exclusion principle
states that no two
species can occupy
exactly the same
niche in exactly the
same
habitat
at
exactly the same
time.
Competition

Division of resources
 By causing species to
divide
resources,
competition
helps
determine
the
number and kind of
species
in
a
community and the
niche each species
occupies.
Competition

Division of resources

Species usually divide
similar resources instead
of competing for them.
Predation, Herbivory, and Keystone Species

Predation-prey relationships
 Predation occurs when one animal captures and feeds on another
animal.
 Predators can affect the size of prey populations in a community and
determine the places prey can live and feed.
Predation, Herbivory, and Keystone Species

Herbivore- Plant Relationships


Herbivory is an interaction in which one animal feeds on
producers.
Herbivores can have major effects on plant survival.
Predation, Herbivory, and Keystone Species

Keystone species is a
single species that can
cause dramatic effects
in the structure of a
community.

Examples: wolf and sea
otter.
Symbiosis



Means “living together.”
Is any relationship in which two species live
closely together.
Biologist recognize three main classes of
symbiotic relationships: mutualism, parasitism,
and commensalism.
Symbiosis

Mutualism
is
a
relationship in which
both species benefit.

Example: sea anemone
and clown fish.
Symbiosis

Parasitism
is
a
relationship in which
one organism lives
inside or on another
organisms and harms it.
Symbiosis

Commensalism
is
relationship in which
one organism benefits
and the other neither
harmed nor helped.

Examples:
barnacles,
remora.
whale
shark
and
and
Assignment

Write a sentence that demonstrates your
understanding of the vocabulary terms on page
99 of your M&L biology textbook. Do not
write the definitions of the terms.