A species that has survived over extended periods of geologic time with little or no change to their appearance and biology. One popular living fossil is the coelacanth, a funny-looking fish that was thought to be extinct for over 80 million years until it was hooked off the coast of South Africa in 1938.

Other examples are the tuatara, a lizard-like reptile from New Zealand, and the Ginkgo and Metasequoia, species of trees often found in parks and botanical gardens.