Living fossil is an informal term for any living species (or clade) of organism which appears to be the same as a species otherwise only known from fossils and which has no close living relatives. These species have all survived major extinction events, and generally retain low taxonomic diversities. A species which successfully radiates (forming many new species after a possible genetic bottleneck) has become too successful to be considered a "living fossil".
Famous quotes containing the words living and/or fossil:
“One of the most significant effects of age-segregation in our society has been the isolation of children from the world of work. Whereas in the past children not only saw what their parents did for a living but even shared substantially in the task, many children nowadays have only a vague notion of the nature of the parent’s job, and have had little or no opportunity to observe the parent, or for that matter any other adult, when he is fully engaged in his work.”
—Urie Bronfenbrenner (b. 1917)
“The earth is not a mere fragment of dead history, stratum upon stratum like the leaves of a book, to be studied by geologists and antiquaries chiefly, but living poetry like the leaves of a tree, which precede flowers and fruit,—not a fossil earth, but a living earth; compared with whose great central life all animal and vegetable life is merely parasitic.”
—Henry David Thoreau (1817–1862)