The variety of life in the world or in a particular habitat or ecosystem is called what?

• A. Population
• B. Biodiversity
• C. Density
• D. Species richness

Answer: (B)

Biodiversity is the overall variety of life in a world, habitat, or ecosystem because it includes not just how many species are present, but also the genetic differences within those species and the variety of ecosystems that exist in that space. While counting species (species richness) tells you how many different species there are, biodiversity goes further by also considering genetic diversity within species and the range of different habitats or ecological roles in an area. Population refers to how many individuals of a species there are, and density is that number per unit area, which describe abundance rather than variety. So biodiversity best captures the full concept of life’s variety.