Three species of lizards of the genus Gallotia are found on the Canary Islands, a chain of seven volcanic islands off the west coast of Africa. The easternmost island, Lanzarote, is the oldest, while the westernmost island, El Hierro, is the youngest. The distribution of lizard species is shown on the map below. Explain how three species of lizards on the Canary Islands evolved from the common ancestor in Africa.

In your explanation include the type of isolation event and describe species and speciation.