Lecture 7 estimating extinction risks from climate change. Part 1 the 6th mass extinction (the anthropocene) continued. Why is genetic diversity important to maintain: genetic factors affecting small populations, two major factors: Increased numbers in population express recessive trait: consequences of inbreeding: Increase inbreeding = less hidden by heterozygosity > natural selection has greater affect (large population size: result: genetically similar but less deleteriously recessive traits. It has a restricted distribution but travels across international boundaries. It is intolerant of man, reproduces in aggregations, and has non-adaptive behavioural idiosyncrasies. : meets all criteria. 2000, mater 2005): agriculture (affects 38% of endangered species, commercial development (35%, water projects (30%, outdoor recreation (27%, livestock grazing (22%, pollution (20%) Island biogeography theory (colonization curve: number of species function of island size and distance from nearest mainland, predict number of species at any given moment. Immigration adds species: extinction removes species, local extinction.