User:Sportsphreak73/sandbox

Mammal species that have been isolated in an island environment have been shown to have different rates of evolutionary change, and other different phenotypic changes like body size when compared to their mainland species equivalent. This phenomenon has been described at the “island effect” or “Foster’s rule”. An evolutionary biologist, Van Valen, in 1973 first introduced us to this based on a study by a mammalogist J. Bristol Foster in 1964. One well known example of these differences is known as Island gigantism, this is when the species isolated on an island is much larger than the same species located on the mainland. These ideas related to the “island effect” is still a topic being explored and debated by current evolutionary biologists.