How does biodiversity sustain a population in an area?

Biodiversity – coined from biological diversity – is most often thought of as the variety of organisms on earth. yet it also includes two other factors: ecological diversity (the variety of ecosystems and ecological communities) and genetic diversity (the range of genetic differences found within and between species). this means that if the physical factor of the area change in any manner, then due to biodiversity, there will be some organisms  of the population which will be better adapted to that change, hence they will survive and in that manner, the population will be sustained in that area. 

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