Biological Diversity or Biodiversity is the variety of the earths living organisms, the genes they contain and the ecosystems they compose. This includes the different species of plants, animals and microorganisms that make up an ecosystem. Biodiversity is a key element in the earth's biosphere- the capability of earth and its atmosphere to support life- due to the earth's dependency on the maintenance of biodiversity and other non-living objects. This is why the preservation and knowing the threats to biodiversity is highly recommended, as we ourselves depend so heavily on biodiversity and can help maintain it for future generations. Although, before knowing the threats we must first identify the different aspects of biodiversity. .
Generally there are three levels of Biodiversity .
a) Genetic Diversity.
b) Species Diversity .
c) Ecosystem Diversity.
Although some researchers argue there are more levels most generally believe that the 3 levels given are an appropriate amount to work with. Genetic Diversity is the variations of genetic composition within a living species. For example all organisms that reproduce sexually, each individual member of that species have a different genetic composition to another member of the same species. This difference between members of the same species is determined by Genes, which consist of Deoxyribonucleic Acid or DNA. DNA determines organism's physical characteristics (for example in humans DNA would determine a persons eye/hair/skin colour) and their abilities or inabilities. .
The level of Genetic Diversity is as important as its preservation. This is because the higher the level of genetic diversity within a species the greater the species ability to adapt to environmental changes. This is opposed to lower levels- meaning invariability within the group-, which would make most of the individual organisms within the group intolerable to dramatic environmental changes.