Ecological Succession

Ecological Succession

Definition of Ecological Succession

The series of predictable changes that occur in a community over time.

Multiple Choice

The series of predictable changes that occur in a community over time is called what?

• Environmental succession

• ecological succession

• Direct succession

• Partial succession

Primary succession

The first step in primary succession is the formation of soil.

(Generally slow, many 1000s of years)

• ​Usually occurs in an area that previously did not support life

• Much slower than secondary succession

Causes of Primary Succession

1.

Volcanic eruptions

2. When glaciers expose
bare rock

Multiple Select

Primary succession occurs ______?

• in an area that did not previously support life

• when glaciers recede

• after volcanic eruptions

• very quickly

Multiple Choice

The first step in primary succession is ______.

• volcanic eruption

• acquiring water

• pioneer species

• formation of soil

Pioneer Species

• First species to colonize bare rock
• Help break up rocks and form soil, so other species can grow.

Multiple Choice

The first species to colonize bare rock is called _______.

• pioneer species

• primary species

• life giving species

• climax species

As soil is formed, plant seeds blown in from other areas will take root

Multiple Choice

One of the main jobs of a pioneer species is to ________.

• Provide habitat for new species

• Decompose organic material

• Break up the rock and form soil

• Cultivate the soil

Lichens

• Lichens are one important group of pioneer species.

• A lichen represents a mutualistic symbiosis.

• Lichens are composed of a fungus and a

photosynthetic organism (algae or bacteria).

Multiple Choice

What is a mutualistic symbiosis?

• a type of ecological interaction where two or more species benefit from each other's presence

• 
  A parasitic relationship where one species benefits and the other is harmed

• A commensalistic relationship where one organism benefits and the other is unaffected

How do lichens help with primary succession?

1.

Secrete acids that help break down rocks

2.

When they die, lichens add organic material to the soil

3. Provide food for other organisms

Multiple Choice

Which is NOT a way in which lichens help with primary succession?

• Secrete acids that help break down rocks

• When they die, lichens add organic material to the soil

• Provide food for other organisms

• Consumer other organisms

Multiple Choice

What is a climax community from the last slide?

• the final and stable community

• An interim community

• A primary community made up of grass and flowers

• The succession community

Secondary Succession

• Occurs when a disturbance changes the existing community

• The soil is not removed

Disturbances that can initiate secondary succession:

• Fire
• Agriculture
• Hurricanes

Multiple Choice

Fire, hurricanes, and agriculture and the only ways that land is disrupted so a secondary succession can take place.

• True

• False

Over time, the plant community changes.

Rock

Pioneer species →

Small plants/grasses → ↓

←Shrubs/bushes

←Small trees

←Larger trees

​Climax Forest

Succession in a Marine

Environment

Whale-fall Community

Very difficult to study!

3 Stages

1.

Whale dies and sinks to ocean floor and attracts decomposers and scavengers

2. Once the tissues are gone, the carcass supports a smaller set of organisms. 

- decomposition enriches the sediments

3. When only the skeleton remains, bacteria begin to decompose the bones.

Multiple Choice

Who conducted the whale fall research in this video?

• Whales-R-Us

• Monterey Bay Aquarium Research Institute

• Sea World Research Institute

• Whale Life Research Group