- the process or result of evolving over many generations from an animal of standard size to one of much increased size, especially evidenced on islands, where the contained environment imparts a strong inclination to territorialism and limits the number of predators, as exemplified by Archaeoindris fontoynontii, an extinct lemur of Madagascar, which evolved to the size of an average gorilla: insular gigantism also occurs in certain plant species, but the studies of such are relatively limited.
