How does the fossil record provide support for evolutionary theory?

The fossil record supports evolutionary theory primarily by showing a chronological sequence of evolution with transitional forms. This means that fossils provide evidence for how complex life has changed over time, illustrating a gradual change from earlier, simpler forms to more complex forms. Transitional fossils act as a bridge between different taxonomic groups, demonstrating characteristics that are intermediate between those of ancestral species and their descendants. For instance, fossils of species such as Archaeopteryx illustrate features of both dinosaurs and birds, highlighting the evolutionary transition from reptiles to birds.

This chronological aspect of the fossil record allows scientists to construct a timeline of evolutionary events, revealing the progressive nature of changes across generations. Such evidence strengthens the argument for common descent, showing not only that life has changed through time but also how various forms are interconnected through their evolutionary history. This becomes a significant piece of the puzzle in understanding the mechanisms and patterns of evolution.