Marine mammal Marine mammal Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They do not represent a distinct taxon or systematic grouping, but rather have a polyphyletic relation due to convergent evolution, as in they do not have an immediate common ancestor. They are also unified by their reliance on the marine environment for feeding. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals
Patagonia (mammal) as opposed to earlier forest environments in the region. This coincides with "Patagonia"'s burrowing, grazing habits. A large variety of mammal species are known, including caviomorph rodents such as "Dudumus", as well as the rodent-like argyrolagoidean paucituberculates. "Patagonia" likely avoided competition in its fairly specialised niche. Patagonia (mammal) Patagonia is an extinct genus of non-placental mammal from the Miocene of Argentina. Traditionally considered a metatherian "incertae sedis", more recent analysis have shown it to be a gondwanathere. It is the youngest allothere species known. Currently, a single species is known, "P. peregrina", hailing from the Colhuehuapian-dating deposits of the Sarmiento