Biodiversity: Concept and Types

Biodiversity: Concept and Types

Biodiversity (biological diversity) is the total variety of life found across every level of biological organisation, from genes within a species up to entire ecosystems. It is conventionally broken down into three interrelated types:

• Genetic diversity — the variation in genes (and hence in traits) that exists within a single species. This can appear as variation between geographically separated populations of the same species (e.g. the many locally adapted varieties/breeds within one species) or as variation among individuals within the same population. Genetic diversity is the raw material for a species' ability to adapt to changing environments.
• Species diversity — the variety of species found within a region, which itself has two components: species richness (the total number of different species present in an area) and species evenness (how evenly individuals are distributed among those species, i.e. whether one or two species dominate or all are represented in comparable numbers).
• Ecological diversity — the diversity of habitats, biotic communities and ecological processes (such as nutrient cycling, energy flow, and species interactions) present within a region or a larger geographical area. It captures diversity at the level of whole ecosystems rather than at the level of genes or species. …