Biological Diversity, Animal Behavior & Endangered Species Study Guide 1. What is biodiversity? What is the underlying cause of biodiversity? Biodiversity is a variety of different species in a specific area. The major cause for lowering biodiversity is the loss of habitat due to human kind activities. 2. Biological diversity involves the following concepts. Explain each: Genetic diversity ? variety of genes in a species to allow for it to have an reproductive advantage Habitat/ecosystem diversity- large area with different biomes for organisms to thrive in. Species diversity- number of different species and their abundance.