1. Traits or characteristics that evolved for one purpose but later became useful for a different function or environment.
Usage: plural form; biology/evolutionary science; also called exaptations

Examples

• Feathers originally evolved in dinosaurs for insulation and display, but they became preadaptations for flight.
• The swim bladder in fish is thought to be a preadaptation that later allowed some species to develop lungs.
• Bird wings are preadaptations—structures that existed before they were used for their current primary function.
• Scientists study preadaptations to understand how evolution repurposes existing traits for new survival advantages.
• The preadaptations present in early mammals eventually enabled the evolution of complex behaviors and larger brains.