Many different indices of landscape pattern have been developed. The growth of landscape ecology owes much to the development of Geographical Information Systems (GIS) technology and the availability of large-extent habitat data (e.g. remotely sensed satellite images or aerial photography). Its theoretical underpinnings originate from MacArthur & Wilson's Island Biogeography theory and subsequent metapopulation theory. Landscape ecology typically deals with problems in an applied and holistic context.