Which concept entails the gradual change of species over time?

The concept that describes the gradual change of species over time is evolution. This process is characterized by the cumulative changes in the inherited characteristics of populations over successive generations. It explains how species can diverge from common ancestors and adapt to their environments, leading to the vast diversity of life observed today.

Evolution is driven by various mechanisms, including natural selection, genetic drift, and gene flow. While natural selection plays a crucial role by favoring traits that enhance survival and reproduction, evolution encompasses a broader scope, detailing not just the survival of advantageous traits but also the overall changes within populations over extended periods.

Adaptation refers to the specific traits or changes that enhance an organism's ability to survive in its environment, but it is a component of the larger evolutionary process. Mutation introduces genetic variation, which can contribute to evolution, but on its own does not account for the broader changes in species over time. Hence, evolution is the term that encapsulates the gradual development and transformation of species across generations.