Precipitation that becomes acidic due to acid-forming precursors put into the atmosphere by human activities.

Members of a class of cold-blooded vertebrates who are aquatic in the larval stage, and breathe air as adults. Frogs, toads, and newts are examples of amphibians.

Caused or influenced by human impact on natural systems.

The natural rate of extinction in the absence of human influence. Estimates of the background rate of extinction range from one to ten species per year, which is 100 to 1,000 times lower than the curr [..]

The variety of living organisms. Biodiversity encompasses variation at all levels, from the genetic diversity within a species to the variation between higher level evolutionary groupings such as fami [..]

An integrated group of biological organisms located in a particular type of habitat, and the physical environment in which they live. The ecosystem includes the living organisms, habitat structure, fa [..]

Native to a particular, restricted geographic area.

The change in organisms over generations that gradually results in changes in populations and species.

The killing, capturing or collecting of wild organisms for human use.

The state in which all members of a groups of organisms, such as a species, population, family or class, have disappeared from a given habitat, geographic area, or the entire world.