Complex sentence: The field was started in the 1960s by the ecologists Robert MacArthur and E.O. Wilson, who coined the term theory of island biogeography, as this theory attempted to predict the number of species that would exist on a newly created island.
Split into simpler sentences: The field was started in the 1960s by the ecologists Robert MacArthur and E.O. Wilson, who created the theory of island biogeography. This theory attempted to predict the number of species that would exist on a newly created island.