IB ESS SL 2.5.7 Succession Changes Over Time Question Bank
Trace changes in diversity, biomass, productivity and stability during succession.
- Syllabus
- First assessment 2026
- Course
- ESS SL
- Level
- SL
Trace changes in diversity, biomass, productivity and stability during succession.

Table:Organisms found in each successional stage

Figure:Keen's mouse in three successional stages
An area of temperate coniferous forest was deforested and allowed to regenerate. A survey of species numbers was conducted in three successional stages. The results of the survey are summarized in Table: Organisms found in each successional stage.
Explain why the diversity changes in the different successional stages.
Species diversity increases toward the later stage...
i. because there is an increase in habitats;
ii. as new species move or are transported into the area;
iii. because primary productivity tends to increase as you move through the stages;
iv. because nutrient cycling becomes more developed;
v. because evenness/richness increases;