An extant species which is morphologically very similar to a species from the ancient past. Despite apparent lack of change, they seem to have escaped extinction. Coelacanth (a 350 million-years-old lobe-finned fish), Horseshoe Crab (a 510 million-years-old marine arthropod), Amazon River Dolphin, Gingko (maidenhair tree, a gymnosperm), and Metasequoia (Metasequoia glyptostrobodes, a conifer) are examples.

A living fossil is an organism that lived during ancient times and still live today, relatively unchanged, like the horseshoe crab. Magnetic Field The Earth's magnetic field is aligned with the north and south poles, and has reversed many times during geologic history. A fossil's magnetic orientation can give clues to its date.

a member of a species that represents a genus or larger grouping in which all the other species have died out

an animal or plant that is both living today and represented in the fossil record

an organism living today that appears to be identical to specimens in the fossil record

an organism that is thought to have been extinct, and then it shows up alive on planet earth

Living fossil is an informal term for any living species (or clade) of organism which seems to be the same as a species otherwise only known from fossils and 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".