Population is defined as any group of organisms of the same species which can interbreed amongthemselves, and occupy a particular space and function as part of a biotic community. A population has various properties like population density, natality (birth rate), mortality (death rate), age distribution, biotic potential, dispersion and ‘r’, ‘K’ selected growth forms. A population possesses genetic characteristics that are directly related to their adaptiveness, reproductive success, and persistence in their habitats over time. Life history of an organism is an important part of this attribute. The population has a definite structure and function that can be described with reference to time.