Biodiversity includes all the variety and variations of living organisms in the earth. These variety of plants and animals have different characteristics , unique features and adaptations for their survival in their living environment developed over the course of evolution. As the time is changing and the environment is also changing rapidly. So there is need of some new features in them for their survival. So cross between same species is carried out to cover the weakness (low chance of survival) in the new living environment. The hybrid offspring from the pure parents tend to have more chances of survival. So, when there is wide variety of plants and animals as they mate with each other and form a new hybrid which improves breed.
