Marine biology gannets, and auks. Although they spend most of their lives in the ocean, species such as gulls can often be found thousands of miles inland. There are five main types of marine mammals, namely cetaceans (toothed whales and baleen whales); sirenians such as manatees; pinnipeds including seals and the walrus; sea otters; and the polar bear. All are air-breathing, and while some such as the sperm whale can dive for prolonged periods, all must return to the surface to breathe. Marine habitats can be divided into coastal and open ocean habitats. Coastal habitats are found in the area that extends
Two Forms (Divided Circle) fire at her studio in St Ives in 1975. It includes two vertical bronze semi-circles forming a broken circle approximately across, each pieced pierced by one large hole. Both elements are welded to a bronze base. All three elements are hollow, and were cast in London by Morris Singer. Hepworth designed the work after being diagnosed with cancer in 1966. She wanted the viewer's body to be engaged with her work, saying: "You can climb through the Divided Circle – you don't need to do it physically to experience it." Hepworth also made a series of nine maquettes about tall,