Second only to primates, cultures in dolphins, whales and porpoises are diverse and advanced. Some of the best-studied cultural behaviors among cetaceans are their vocalizations. Bottlenose dolphin, humpback whale, killer whale, and sperm whale songs and clicks are widely unique among different groups. In fact, researchers now acknowledge that these vocal differences are sufficient enough to be considered different dialects. Furthermore, different groups of some species, such as orcas, exhibit radically unique hunting techniques, and even diverse tastes in food, including the proclivity to hunt entirely different kinds of prey than other groups.