How do fossils help scientists study evolution?

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A vertical geologic time scale chart spanning from 650 million years ago to the present, with colored bands for each era and period. Illustrations and labels highlight key evolutionary events such as the appearance of skeletal elements, first fishes, land plants, amphibians, reptiles, dinosaurs, mammals, and humans. — evolution The geologic time scale from 650 million years ago to the present, showing major evolutionary events.

Fossils are crucial for understanding evolution because they provide a historical record of life on Earth. By examining fossils, scientists can observe progressive changes within animal and plant groups over geological time. These changes, often interpreted as adaptations to different environments, help trace the evolutionary paths of species.12

Fossils also aid in dating rock layers, allowing scientists to place evolutionary events in chronological order. The discovery of transitional fossils, which exhibit characteristics of both ancestral and derived forms, offers direct evidence of evolutionary links between different groups. For instance, fossils have been instrumental in understanding the evolution of vertebrates and primates.13456