logging, poor soil conservation in agriculture and the illegal wildlife trade. Overexploitation can lead to resource destruction, including extinction. Artificially developed projects can cause damage to the surrounding environment About 25% of world fisheries are now overfished to the point where their current biomass is less than the level that maximizes their sustainable yield. The overkill hypothesis, a pattern of large animal extinctions connected with human migration patterns, can be used to explain why megafaunal extinctions can occur within a relatively short time period. Hybridization, genetic pollution/erosion and food security In agriculture and animal husbandry, the Green Revolution popularized the use of conventional hybridization to increase yield. Often hybridized breeds originated in developed countries and were further hybridized with local varieties in the developing world to create high yield strains resistant to local climate and diseases. Local governments and industry have been pushing hybridization. Formerly huge gene pools of various wild and indigenous breeds have collapsed causing widespread genetic erosion and genetic pollution. This has resulted in the loss of genetic diversity and biodiversity as a whole. Genetically modified organisms contain genetic material that is altered through genetic engineering. Genetically modified crops have become a common source for genetic pollution in not only wild varieties, but also in domesticated varieties derived from classical hybridization. Genetic erosion and genetic pollution have the potential to destroy unique genotypes, threatening future access to food security. A decrease in genetic diversity weakens the ability of crops and livestock to be hybridized to resist disease and survive changes in climate. Climate change Global warming is a major threat to global biodiversity. For example, coral reefs – which are biodiversity hotspots – will be lost within the century if global warming continues at the current rate. Climate change has proven to affect biodiversity and evidence supporting the altering effects is widespread. Increasing atmospheric carbon dioxide certainly affects plant morphology and is acidifying oceans, and temperature affects species ranges, phenology, and weather, but, mercifully, the major impacts that have been predicted are still potential futures. We have not documented major extinctions yet, even as climate change drastically alters the biology of many species. In 2004, an international collaborative study on four continents estimated that 10 percent of species would become extinct by 2050 because of global warming. "We need to limit climate change or we wind up with a lot of species in trouble, possibly extinct," said