Biological diversity or biodiversity refers to the diversity, or variety, of plants and animals and other living things on earth. There are many levels of diversity-from DNA and genes to species, populations, ecosystems, and communities. This diversity is the beauty of nature and is essential for the survival of human beings. Life on Earth would not exist if its rich biodiversity were severely altered. Species and the ecosystems in which they live are linked together though the flows of energy and materials. A change in the life of one species could ripple throughout an ecosystem, changing...