Download Species Relationship notes

• Symbiosis is a relationship between
different species in which at least one
species depends upon the relationship to
survive
Symbiotic relationships
• Symbiosis
– Mutualism (+ +)
– Commensalism (+ 0)
– Antagonism (+ -)
• Parasitism
• Predation
• Competition
– Amensalism (- 0)
Antagonism Predation
• One individual (predator) captures, kills,
and consumes another individual (prey)
Common Defenses Against Predation
• Flight
• Mimicry
• Camouflage
• Chemicals/Physical Structures
• Bright Colors
Herbivore-Plant Interactions
• An herbivore
grazing on a
plant is another
example of
predation.
• Usually, only
part of the prey
is eaten by the
predator.
•
Photo Credit: Rhett A. Butler @
mongabay.com
Antagonism - Competition
• Competition in an interaction between two
organisms that are using the same resources
• Competition within the same species= intraspecific
• Competition between different species= interspecific
• One organism better uses a resource leaving
less for other species
Example: Interspecific Competition
• Two species of barnacles on rocky coasts
often compete for space.
• The smaller species (Chthamalus) is
unable to compete as well as the larger
species (Balanus).
• However, Chthamalus can survive drying
better than Balanus, so it can live higher
up on the rocks.
Experiment: Interspecific Competition
• In Scotland,
Joseph Connell
studied
interspecific
competition in
these two
barnacles.
• In places where
both barnacles
were present, he
removed the
Balanus
barnacles from
the rocks.
Experiment: Interspecific Competition
• When Balanus
barnacles were
removed, the
Chthamalus
barnacles moved
down into the
vacant area.
• This showed that
Balanus was
outcompeting
Chthamalus in
the lower zone.
Experiment: Interspecific Competition
• At other sites where both barnacles were
present, he removed Chthamalus
barnacles from the rocks.
• The vacant areas remained unoccupied.
• This showed that Balanus was not able to
survive in the upper zone.
Antagonism - Parasitism
• One individual is
harmed and one
benefits
• Parasite feeds on the
host
– No immediate death
Mutualism
• Both species benefit
– Pollination
Commensalism
• One species benefits and the other is not
affected
– Cattle Egrets and Livestock
Ammensalism
• one species is harmed or inhibited and the
other species is unaffected
– shading out of one plant by a taller and wider one
– the inhibition of one plant by the secretions of
another
Species Interactions
Symbiotic Relationship Species 1
+
Mutualism
Benefits
+
Commensalism
Benefits
Antagonism (Parasitism,
competition,
+
predations)
Benefits
Ammensalism
Harmed
Species 2
+
Benefits
0
Neutral
Harmed
0
Neutral
• http://education.nationalgeographic.org/act
ivity/ecological-relationships/
• https://www.youtube.com/watch?v=fxrzdh
Hjf0Q&list=PL0EA301D130F3DB40
– Clips 1-3