How do fossils enhance our understanding of human evolution?

Fossils enhance our understanding of human evolution by serving as a record of physical changes over time. They capture the anatomical characteristics of our ancestors and relatives, allowing researchers to trace the gradual transformations in size, shape, and structure across different species. This record reveals key adaptations that occurred in response to environmental pressures, such as changes in climate, diet, and locomotion. By studying these changes in the fossilized remains, scientists can construct a more comprehensive picture of how modern humans have evolved from earlier primate ancestors.

The other options do not accurately reflect the primary function of fossils in the study of evolution. While fossils can provide context about the environments where these species lived, they do not predict future evolutionary changes or directly highlight social structures. Their most significant contribution lies in documenting the physical evidence of evolutionary processes over time.