Transcript Predation - BAschools.org

ECOLOGY
INTERACTIONS
Types of ecological interactions
competition
predation
parasitism
mutualism
commensalism
symbiosis
Competition – two species share a requirement for a
limited resource  reduces fitness of one or both species
Predation – one species feeds on another  enhances
fitness of predator but reduces fitness of prey
herbivory is a form of
predation
Parasitism – one species feeds on another  enhances
fitness of parasite but reduces fitness of host
Mutualism – two species provide resources or services
to each other  enhances fitness of both species
Commensalism – one species receives a benefit from
another species  enhances fitness of one species; no
effect on fitness of the other species
Symbiosis – two species live together  can include
parasitism, mutualism, and commensalism
Organizing ecological interactions
effect on species 1
+
effect on
species 2
+
mutualism
0
commensalism
-
predation
herbivory
parasitism
0
-
commensalism
predation
herbivory
parasitism
competition
competition
competition
VIDEO
• Elements of Biology: Ecosystems: Organisms and
Their Environment
• http://www.pbs.org/wnet/nature/lessons/symbioticstrategies/video-segments/1496/
• Assignment: Ecological Interactions Quiz
13.2 RESEARCH QUESTIONS
1) Name two ways in which members of the same
species interact.
2) In what ways do members of different species
interact?
3) Think of a biological community near you, and
give an example of how population has affected
another.
4) Explain how symbiotic relationships are similar to
and different from predator-prey interactions.