Biodiversity

Biodiversity is the total richness of biological variation. The scope of biodiversity is usually considered to range from the genetic variation of individual organisms within and among populations of a species, to different species occurring together in ecological communities. Some definitions of biodiversity also include the spatial patterns and temporal dynamics of populations and communities on the landscape. The geographical scales at which biodiversity can be considered range from local to regional, state or provincial, national, continental, and ultimately to global.

Biodiversity at all scales is severely threatened by human activities; this is one of the most important aspects of the global environmental crisis. Humans have already caused permanent losses of biodiversity through the extinction of many species and extensive losses of distinctive, natural ecosystems. Ecologists predict that unless there are substantial changes in the ways that humans affect ecosystems, there will be much larger losses of biodiversity in the near future.