DSST Environmental Science Practice Exam 2026 - Free Environmental Science Practice Questions and Study Guide

Biodiversity refers to biological diversity, which encompasses the variety of species within a given area. This definition highlights not just the number of species present, but also the different ecosystems they inhabit, the genetic variation within those species, and the complex interactions that occur among them. Biodiversity is crucial for ecosystem resilience, providing stability and a richness of resources that can lead to better adaptability in the face of environmental changes.

In the context of environmental science, understanding biodiversity is essential because it directly impacts ecological health and the services ecosystems provide, such as clean air, water, and food resources. A high level of biodiversity typically indicates a robust ecosystem capable of withstanding stressors like pollution and climate change.

The other options focus on narrower aspects of biological concepts; for instance, the number of individuals in a population pertains to population dynamics rather than species diversity, while genetic variations focus on a single species rather than the broader picture of interspecies diversity. The average lifespan of species may be an interesting demographic characteristic but does not capture the essence of diversity itself. Thus, the correct definition of biodiversity is integral to understanding ecological relationships and conservation efforts.