Volcano of classifying magmatic volcanoes is by their frequency of eruption, with those that erupt regularly called active, those that have erupted in historical times but are now quiet called dormant or inactive, and those that have not erupted in historical times called extinct. However, these popular classifications—extinct in particular—are practically meaningless to scientists. They use classifications which refer to a particular volcano's formative and eruptive processes and resulting shapes. There is no consensus among volcanologists on how to define an "active" volcano. The lifespan of a volcano can vary from months to several million years, making such a distinction sometimes
Extinct in the wild survival techniques, which are often passed from parents to offspring during parenting, may be lost. While conservation efforts may preserve some of the genetics of a species, the species may never fully recover due to the loss of the natural memetics of the species. An example of a successful reintroduction of an EW species is Przewalski's horse, which as of 2018 is considered to be an Endangered species, following reintroduction started in the 1990s. Extinct in the wild An extinct in the wild (EW) species is one which has been categorized by the International Union for Conservation of Nature as