Neontology is a part of biology that, in contrast to paleontology, deals with living (or, more generally, recent) organisms. It is the study of extant taxa (singular: extant taxon): taxa (such as species, genera and families) with members still alive, as opposed to (all) being extinct. For example:

• The moose (Alces alces) is an extant species, and the Irish elk (Megaloceros giganteus) is an extinct species.
• In the group of molluscs known as the cephalopods, as of 1987 there were approximately 600 extant species and 7,500 extinct species.

A taxon can be classified as extinct if it is broadly agreed or certified that no members of the group are still alive. Conversely, an extinct taxon can be reclassified as extant if there are new discoveries of living species ("Lazarus species"), or if previously known extant species are reclassified as members of the taxon.

Most biologists, zoologists, and botanists are in practice neontologists, and the term neontologist is used largely by paleontologists referring to non-paleontologists. Stephen Jay Gould said of neontology:

All professions maintain their parochialisms, and I trust that nonpaleontological readers will forgive our major manifestation. We are paleontologists, so we need a name to contrast ourselves with all you folks who study modern organisms in human or ecological time. You therefore become neontologists. We do recognize the unbalanced and parochial nature of this dichotomous division.

Neontological evolutionary biology has a temporal perspective between 100 and 1000 years. Neontology's fundamental basis relies on models of natural selection as well as speciation. Neontology's methods, when compared to evolutionary paleontology, have a greater emphasis on experiments. There are more frequent discontinuities present in paleontology than in neontology, because paleontology involves extinct taxa. Neontology has organisms actually present and available to sample and perform research on. Neontology's research method uses cladistics to examine morphologies and genetics. Neontology data has more emphasis on genetic data and the population structure than paleontology does.