What You Need to Know

Key Concept Diagram

A biome is a large region characterised by its climate, plants, and animals (e.g., tropical rainforest, desert, tundra)

Primary succession begins on bare rock with no soil; pioneer species create conditions for others

Secondary succession occurs after disturbance when soil remains; it proceeds faster than primary succession

A climax community is the stable end state of ecological succession

Keystone species have disproportionate effects on their ecosystem relative to their abundance

Key Vocabulary

Biome

A large ecosystem defined by its climate, vegetation, and characteristic species

Primary succession

Ecological succession beginning on lifeless substrate such as bare rock

Climax community

The final, stable community reached at the end of ecological succession

Keystone species

A species whose removal would cause dramatic changes to the ecosystem

Knowledge Check

Select the correct answer for each question. Click "Check Answer" to see if you are right.

Question 1

What distinguishes primary succession from secondary succession?

Primary succession is faster than secondary succession Secondary succession only occurs in water Primary succession begins on bare substrate with no soil; secondary begins where soil remains There is no difference

Question 2

A keystone species is one that:

Is the most numerous species in the ecosystem Competes with all other species Only exists in one biome Has a disproportionately large effect on the ecosystem relative to its abundance

Question 3

Which biome is characterised by high rainfall, high biodiversity, and year-round warm temperatures?

Tropical rainforest Tundra Desert Temperate grassland

Advanced Ecology: Biomes and Succession