Evolutionary biology is the study of how living organisms change over time through processes like natural selection, mutation, and genetic drift. It explores the relationships between different species and how they adapt to their environments, leading to the diversity of life we see today. This field combines insights from various disciplines, including genetics, paleontology, and ecology. By examining fossils, DNA, and the behavior of organisms, evolutionary biologists aim to understand the history of life on Earth and the mechanisms that drive evolutionary change.