1. Conservation Biology Human Activities Threaten Biodiversity! Conservation biology is concerned with maintaining the natural diversity in ecosystems. The three levels of diversity are: – Genetic Diversity As populations are removed from a species their ability to adapt also decreases. – Species Diversity Is concerned with species richness throughout the entire biosphere. – The Endangered Species Act defines an endangered species as one that has lost a significant portion of its species diversity throughout its range. – A threatened species is one that is likely to become endangered in the near future. – Ecosystem Diversity Concerned with the loss or conversion of native ecosystems or alteration due to loss of a keystone species.

2. Human Threats to Biodiversity Habitat destruction – Estimated that 73% of lost species are directly due to loss of habitat Introduced species – Introduced species often out compete native species for resources or eliminate native species through predation. Over exploitation – Using a resource faster than can be replaced in nature. Large species are at particular risk due to the time it takes to reach maturity. Disruption of interaction networks – The elimination of a keystone species or ecosystem engineer can have dramatic effects on those dependent on them.

3. Benefits of Biodiversity Ecosystem Services – Purification of air and water – Reduction in severe weather – Maintenance of soil fertility – Detoxification of waste – Pollination of crops – Dispersion of seeds – Cycling of nutrients – Control of pests – Erosion control – UV protection