What is biodiversity?

Biodiversity refers to the variety of life in a particular ecosystem or on Earth as a whole. This concept encompasses not only the number of different species (species diversity) but also includes the genetic diversity within species and the variety of ecosystems themselves (ecosystem diversity). Biodiversity plays a critical role in the resilience and functioning of ecosystems, influencing processes like nutrient cycling, pollination, and climate regulation.

The focus on the variety of life highlights the interconnectedness of all living organisms, where the presence of diverse species contributes to the stability and productivity of ecosystems. This definition recognizes the importance of maintaining a rich tapestry of life, which is essential for environmental health and sustainability.

In contrast, other options provide narrower definitions. The total biomass of a region limits the understanding of biodiversity solely to the weight of living organisms rather than their variety. The number of species at extinction risk does not encompass all aspects of biodiversity, as it only focuses on specific threats without considering the full scope of life forms present. Lastly, while genetic variation within a single species is a vital component of biodiversity, it is just one facet of a much broader concept that includes species and ecosystem diversity as well.