Download 4.3 Succession File

Succession
POINT > Describe primary succession in
ecosystems
POINT > Describe secondary succession in
ecosystems
POINT > Define a climax community
WB CHECK:
Bees help flowers reproduce by spreading pollen.
The bees benefit by getting energy-rich pollen. What
type of symbiosis is this?
Triggerfish move large rocks on the seafloor to find
food. Smaller fish, which could not move the rocks,
benefit by getting new feeding opportunities. What
type of symbiosis is this?
What type of symbiosis occurs when you get a
mosquito bite?
POINT > Describe succession in ecosystems
Succession is a series of relatively predictable
changes that occur in an ecosystem over time
Succession occurs after ecological disturbances or
as some species die and others replace them
WB CHECK:
What is one reason succession occurs?
POINT > Describe primary succession in ecosystems
Primary succession occurs after a major ecological
disruption in an area with no remnants of an older
community
(Ex. volcanic eruptions, retreating glaciers)
POINT > Describe
succession in ecosystems
Primary succession begins in an area with no remnants
of an older community
Pioneer species: The first species to colonize lifeless
areas ex. lichen
POINT > Describe secondary succession in ecosystems
Secondary succession occurs when a disturbance
disrupts an ecosystem without totally destroying it
Seeds and root systems may still be present
Ex. after wildfire, hurricane, etc
POINT > Describe secondary succession in ecosystems
Secondary succession proceeds faster than primary
succession because the soil and some species
survive the disturbance
POINT > Describe secondary succession in ecosystems
Succession occurs as one organism alters the
environment, and allows other species to compete for
resources
For example, new grasses grow after a fire. This
allows herbivores to move into the area and survive
WB CHECK:
What is a pioneer species?
What type of succession would you expect after
a tsunami?
Why is secondary succession faster?
WB CHECK:
What is the difference between primary and
secondary succession?
a) Secondary succession takes longer to occur
b) Secondary succession occurs when remnants
of the original ecosystem are still in place
c) Secondary succession occurs after an
ecosystem has been completely destroyed
POINT > Define a climax community
A climax community is the end result of ecological
succession, and can be very stable
POINT > Define a climax community
After natural disasters ecosystems often recover to
the original climax community
After human disruption (like farming) ecosystems
may or may not fully recover, depending on the
extent of damage
WB CHECK:
A climax community:
a)
b)
c)
d)
changes rapidly as the ecosystem changes
is dominated by pioneer species
only occurs after primary succession
can be a stable, long term ecosystem
Homework:
 Read
pages 106-109
 Assess page 109 #1-2
 Workbook Pages 353, 363-366