3.1.1—Biodiversity levels
- Syllabus
- First assessment 2026
- Objective
- 3.1.1
- Level
- SL
Classify Biodiversity at Habitat, Species and Genetic Levels
Biodiversity has three linked levels: variety of habitats, variety and abundance of species, and heritable variation within species.
Ask what is varying before choosing the level. A landscape comparison is habitat diversity; species counts and evenness are species diversity; differences among populations or individuals are genetic diversity.
Four forest types in one region show habitat diversity; different beetle species show species diversity; drought-tolerant alleles show genetic diversity.
Genetic diversity, because the variation is within the species.
Species richness alone is not the whole of biodiversity; level and abundance matter.