Found in Arctic waters around Canada and Greenland, narwhals are easily recognizable due to their long, ivory tusks. In truth, only the males have the prominent spiral tusk; it's a canine tooth. Like their closest relative, the beluga, narwhals have forehead melons for echolocation. They also lack a dorsal fin, which helps them preserve body heat and swim with ease under ice sheets.
Narwhals are especially adapted for deep sea diving and perform some of the deepest dives of any marine animal, venturing nearly 1,000 feet down. Their flexible rib cage allows them to withstand the intense pressure of deep water, and they are especially equipped to carry oxygen for long periods, as well as minimize oxygen consumption.
Amazing Cold-Weather CreaturesThese 15 animals thrive in extremely cold climates around the world