Marine Mammals: A Comprehensive Study

Marine mammals are the aquatic organisms that depend on the ocean and other marine ecosystems for their survival. Such organisms include sea otters, seals, manatees, whales and polar bears. The adaptation of marine mammals to an aquatic lifestyle varies from species to species. Some mammals such as cetaceans and sirenians are fully aquatic. Animals such as seals and sea lions are semiaquatic. They spend a major part of their life inside water but they need to come to land to perform some sp...