Most of the Galapagos Islands are located very close to the Equator Line in the Southern Hemisphere. Genovesa Island is one of the few in the Northern Hemisphere. This fact influences the water temperature and the adaptation of some species. The prickly pear cacti here have soft spines due to the lack of terrestrial reptiles that would eat them. Similarly, the lack of a top predator like the Galapagos hawk means that a nocturnal animal like the short-eared owl hunts during the day. Genovesa also has the smallest marine iguanas in the Galapagos.