The notes include the following following dot points from QCAA: • recognise that biodiversity includes the diversity of species and ecosystems • determine diversity of species using measures such as species richness, evenness (relative species abundance), percentage cover, percentage frequency and Simpson’s diversity index • use species diversity indices, species interactions (predation, competition, symbiosis, disease) and abiotic factors (climate, substrate, size/depth of area) to compare ecosystems across spatial and temporal scales • explain how environmental factors limit the distribution and abundance of species in an ecosystem. • Mandatory practical: Determine species diversity of a group of organisms based on a given index.