1. of or relating to a trait or characteristic that exists before an organism faces the environmental pressure for which it becomes advantageous; existing prior to the selective pressure that makes it adaptive
Usage: biology; evolutionary biology

Examples

• The fish's ability to breathe air was preadaptive; it evolved before the species moved to shallow waters where that skill became essential.
• Scientists debate whether certain preadaptive features in early mammals later enabled their success after the dinosaur extinction.
• The preadaptive traits of ancestral birds, such as feathers, may have originally served thermoregulation rather than flight.
• Preadaptive structures sometimes provide unexpected advantages when environmental conditions change.