Transcript ecological succession

COMMUNITY
ECOLOGY
What is a community?
• Many species living closely
together, so that they interact
with each other.
• What is a species?
Interspecific Interactions
• Interaction between 2 or more
species that use the same
resource
• Competition must occur:
–interference competition - actual
fighting occurs
–interspecific competition consumption or use of similar
resource
Competitive Exclusion Principle
What is meant by an
ecological niche?
Fundamental / Realized
Niches
Resource Partitioning of
Lizards
Character Displacement
Among the Galapagos Finches
Symbiosis
• Close association between
two species
Mutualism Between Ants
and Acacia Tree
Clownfish Among
Sea Anemone’s Tentacles
Cleaning Symbiosis
A cleaner wrasse, in the mouth of
a spotted sweetlip fish
Commensalism
With Epiphytes
Commensalism: Cape Buffalo and Cattle Egrets
Staghorn Fern.
an Epiphyte
Parasitism
Camouflage in the Anglerfish
Swallowtail Butterfly
Anti-predatorLarva
Defenses
South
American
Lantern
Fly
Batesian Mimicry
Hawk Moth
Larva
Green Parrot
Snake
Müllerian mimicry: Cuckoo bee
(left), yellow jacket (right)
Mimicry Among Insects
Batesian (a, b, c); Mullerian (d, e)
Flower Fly
Longhorn Beetle
Moth
Yellowjacket
Bumblebee
Aposematic Coloration
Nudibranch
Chemical
Defense
and
Aposematic
coloration
are seen
here:
Cryptic
coloration
is seen
here
Deceptive Coloration: Moth with
“Eyeballs"
Parasites are also +/- Symbiotic
Interaction
• Endoparasites
• Ectoparasites
• Parasitoids - insects (usually
wasps) that lay eggs on other
insects and larvae feed on the
host.
Plant Defenses Against
Predators:
What defense
is seen here?
Other Defenses:
• Chemicals that cause plant to
taste bad
Interspecific Interactions:
• What is coevolution?
What
factors will be the
most significant in
determining the structure
of a community?
Species Diversity
Combination of two factors:
1) Richness - number of
different species
2) Relative Abundance number of individuals in
each species
Trophic Structure
• The different feeding relationships
between organisms
• According to the “rules of ten,”
approximately 10% of the potential
energy stored in the bonds of organic
molecules at one trophic level fuels
the growth and development of
organisms at the next trophic level
.
Trophic Structure
• Five examples:
1. Primary Producers
2. Primary Consumers
3. Secondary Consumers
4. Tertiary Consumers
5. Decomposers and Detrivores
Trophic Structure
Tertiary Consumer: snake (10 KCAL)
Secondary Consumer: mouse (100 KCAL)
Primary Consumer: grasshopper
(1,000 KCAL)
Primary Producers: grass (10,000 KCAL)
Species with a Large Impact
•Dominant Species
•Keystone Species
All of the organisms above depend on the sea
otter directly or indirectly for their survival. It
is an example of a keystone species.
Sea Otters as Keystone
Predators
Disturbances Influence Species
Diversity and Composition
• Ex: Succession – predictable
changes that occur in a
community over time
primary succession – no
soil exists initially
secondary succession existing community was
disturbed and returned to
original state.
Moss, a Characteristic
Pioneer Species
Sporophytes
Gametophytes
Lichens
Moss
These are classic pioneer
species.
Lichens
Large-scale Disturbance:
Eruption of Mount St. Helens
Patchiness and Recovery Following
a Large-Scale Disturbance
Secondary Succession
Eventually
a climax
community
usually
results.
Climax Community
• Community that remains
essentially the same over long
periods of time.
• It is the final stage of
ecological succession.
Name the three types of
symbiotic relationships.