ability

Unfurling fiddlehead of the Christmas fern (Polystichum acrostichoides). Credit: Jacob S. Suissa, CC BY-ND Imagine a photograph of your great-grandparents, grandparents and parents side by side. You’d see a resemblance, but each generation would look distinct from its predecessors. This is the process of evolution in its simplest form: descent with modification. Over many generations