Complex sentence: Rafting has played an important role in the colonization of mammals on isolated land masses, such as Madagascar, which has been isolated for ~ 120 million years (Ma), and South America, which was isolated for much of the Cenozoic.
Split into simpler sentences: Rafting has played an important role in the colonization of isolated land masses by mammals. Prominent examples include Madagascar, which has been isolated for ~ 120 million years (Ma), and South America, which was isolated for much of the Cenozoic.