The loss of Biodiversity will be the downfall of Mankind.

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The continuous decline in biodiversity is important not only for scientific curiosity or aesthetics reasons, but because humans depend on the biological resources of the earth for existence. Biological diversity provides a range of services which include provisioning (for example food, clean air, fresh air, and food), regulating (control of pest and diseases, regulating climate), supporting and cultural services. These services all depend on biological diversity of the species in an area and some which are most likely to be public in nature

A loss in this biodiversity will result in destabilization of the ecosystem, outbreak of infectious disease, food insecurity, malnutrition, soil infertility, poverty, limited access to quality and quantity of water, and ecosystem functioning.
Taking a closer look in the tropics, losses of tropical moist forests have intense and far-reaching effects on the ecosystem including: soil erosion, changes in climate (especially rainfall patterns), increase in emissions of "greenhouse" gases, which promote global climate and changes in biological productivity.

The loss of most species are unknown and thus their potential pharmaceutical, agricultural, shelter for other species, recycling of nutrients and environmental values disappear with them. Another consequent is the loss of entire assemblage of species both known and still to be discovered.

Loss in biodiversity will result in economic and social problems. This is because human prosperity is very much based on the ability to use biological diversity and to take advantage of the properties of plants, animals, fungi, and microorganisms as sources of medicine, food, shelter, and clothing.