John Charles Avise (born 1948) is an American evolutionary geneticist, conservationist, natural historian, and prolific science author.

[1] In 1972, Avise published the first multi-locus allozyme analysis in any fish species, and uncovered the profound effects of inbreeding and genetic drift in nature.

During the 1970s and 1980s, his protein-electrophoretic work on many fishes, mammals, birds, and other creatures demonstrated that natural populations are genetically highly polymorphic and that molecular markers can be utilized to address many natural-history topics that previously had been analyzed solely from phenotypic data.

Beginning in the 1990s, Avise capitalized upon highly polymorphic microsatellite loci to analyze animal mating systems in nature, on creatures ranging from sea spiders and snails to polyembryonic armadillos to numerous fishes, including male-pregnant pipefishes and seahorses, and hermaphroditic killifishes.

In 2006, Avise helped to inaugurate a series of annual Colloquia, sponsored by the National Academy of Sciences, broadly entitled "In the Light of Evolution" (ILE).

Proceedings of ten ILE colloquia were published in special issues of PNAS, and eight of them also appeared as edited books from the National Academies Press.

students and 11 postdocs, nearly all of whom went on to assume faculty positions or similar professions around the world, thereby seeding many institutions with researchers in the fields of molecular ecology, natural history, phylogeography, and evolution.