20.1: SPECIES
INTERACTIONS
(PART II)
•
Competition and predation are two
important ways in which organisms
interact.
1. Competition- occurs when two
organisms fight for the same limited
resources (2 types)
1. Competition- occurs when two organisms fight
for the same limited resources (2 types)
• Intraspecific competition - competition
between organisms of same species
• Example: Zebras fighting for mates
Competition- occurs when two organisms fight for
the same limited resources (2 types)
• Intraspecific competition - competition
between organisms of same species
o Example: Zebras fighting for mates
• Interspecific competition- competition
between different species
o Example: Different types of barnacles
compete for rock space
Interspecific competition LEADS TO….
i. Competitive exclusion- when two species are
competing for same resources and one species will
be better suited to the niche
• Two outcomes:
1. other species will be pushed
into another niche (niche
partitioning)
2. OR become extinct
•
niche partitioning- dividing of niche by
two competing species (e.g. top or tree, or
bottom of tree)
2. Predation- process by which one organism
captures and feeds upon another organism.
CLASS WORK
Community Interactions Chart and Scenarios