Marineland has many animals throughout the park that are not cetaceans or pinnipeds. Drinking is not common behavior in pinnipeds and cetaceans. The forelimbs of cetaceans, pinnipeds, and sirenians presents a classic example of convergent evolution. Non-vocal communication is not as common in pinnipeds as in cetaceans. Whales, pinnipeds, and kelp spread. Bears' closest living relatives are the pinnipeds, canids, and musteloids. A ferocious walrus, "Pelagiarctos" may have preyed upon other species of pinnipeds including "Allodesmus". Monk seals have two pairs of retractable abdominal teats, unlike most other pinnipeds. The caniforms include the dogs, bears, raccoons, weasels, and pinnipeds. Aside from the pinnipeds, dogs, bears, hyenas, and cats have distinct and recognizable appearances. Similar to most pinnipeds, the harp seal exhibits a carnivorous diet. Musteloids share a common ancestor with the pinnipeds, the group which includes seals. The coastal marine environment remained productive, as indicated by fossils of pinnipeds. In pinnipeds the limbs have been modified into flippers. The mating system of pinnipeds varies from extreme polygyny to serial monogamy.