Download Types of Community Interactions

Habitat vs. Niche
Habitat- the
place in which
an organism
lives out its
life
Niche - the role
a species plays in
a community; its
total way of life
A niche is
determined by
the tolerance
limitations of an
organism, or a
limiting factor.
Competitive Exclusion
Principle
• No two species can occupy the same niche in
the same place at the same time.
• One species will be eliminated from a
community because of competition for the
same limited resource.
Limiting Factors
• Limiting factor- any biotic or
abiotic factor that restricts the
existence of organisms in a
specific environment or causes
population growth to decrease.
• Most of the time the limiting
factor is a resource in insufficient
supply.
Limiting Factors
Examples of limiting factors •Amount of water
•Amount of food
•Temperature
•Amount of space
•Availability of mates
Limiting Factors
• Density-dependent limiting factor
— factor that only limits growth of
a population when the population
density reaches a certain level
(overcrowding).
• Examples: food, water, shelter,
competition, predation, parasitism, and
disease
Limiting Factors
• Density-independent limiting
factors — these limit growth
regardless of the population size.
• Examples: unusual weather, natural
disasters, seasonal cycles, and human
activities
Resources
• Renewable Resources—a resource
that can regenerate quickly and that
is replaceable.
– Examples: sunlight, trees, etc…
Resources
Nonrenewable Resources—a
resource that cannot be replenished
by natural processes.
Example: fossil fuels
Competition—interaction in which
organisms
of the same or different
Competition
species attempt to use the same
ecological resource in the same
place at the same time.
Predator/Prey—interaction in
which one organism captures,
Predation
KILLS, and feeds on another
organism.
Symbiotic Relationships
Symbiosis- two species living together
http://www.youtube.com/watch?v=zSmL2F1t81Q
3 Types of
symbiosis:
1. Commensalism
2. Parasitism
3. Mutualism
Type of
Species
relationship
harmed
Commensalism
Parasitism
Mutualism
= 1 species
Species
benefits
Species
neutral
Symbiotic Relationships
Commensalismone species benefits
and the other is
neither harmed nor
helped
Ex. orchids on a tree
Epiphytes: A plant, such as a tropical orchid
or a bromeliad, that grows on another plant
upon which it depends for mechanical support
but not for nutrients. Also called xerophyte,
air plant.
Symbiotic Relationships
Commensalismone species benefits
and the other is
neither harmed nor
helped
Ex. polar bears and
cyanobacteria
Commensalism
Whale & Barnacles
Shark & Remora
Symbiotic Relationships
Parasitismone species benefits (parasite) and
the other is harmed (host)
• Parasite-Host relationship
Symbiotic Relationships
Parasitism- parasite-host
Ex. lampreys,
leeches, fleas,
ticks, tapeworm,
Not considered predator-prey
because goal is not to KILL host
Symbiotic Relationships
Mutualism- beneficial to both species
Cleaner Shrimp & Fish
Bee & Flower
Mutualism
Egyptian
Plover
&
Crocodile
Symbiotic Relationships
Mutualismbeneficial to both species
Fungus
+
Bluegreen
Algae
Lichen