In biology, keys are systematic ways to identify organisms and are based on contrasting features, known as contrasting characters. Typically presented as a series of choices, or couplets, each choice leads you closer to the identification of the organism. For example:
- If the flower is red, go to step 2.
- If the flower is not red, go to step 3.
Such keys are invaluable in taxonomy. They simplify the identification process by presenting a series of either/or choices based on observable traits, and each decision branch narrows down the possibilities. Keys are an excellent tool for anyone engaged in biological classification or studies.