Acclimatisation societies were voluntary associations, founded in the 19th and 20th centuries, that encouraged the introduction of non-native species in various places around the world, in the hope that they would acclimatise and adapt to their new environments. The societies formed during the colonial era, when Europeans began to settle in numbers in unfamiliar locations. One motivation for the activities of the acclimatisation societies was that introducing new species of plants and animals would enrich the flora and fauna of target regions. The movement also sought to establish plants and animals that were familiar to Europeans, while also bringing exotic and useful foreign plants and animals to centres of European settlement.

Isidore Geoffroy Saint-Hilaire was a French zoologist and an authority on deviation from normal structure. In 1854 he coined the term éthologie (ethology).