Sheep ideal research subjects, and thus are not a common model organism. They have, however, played an influential role in some fields of science. In particular, the Roslin Institute of Edinburgh, Scotland used sheep for genetics research that produced groundbreaking results. In 1995, two ewes named Megan and Morag were the first mammals cloned from differentiated cells. A year later, a Finnish Dorset sheep named Dolly, dubbed "the world's most famous sheep" in "Scientific American", was the first mammal to be cloned from an adult somatic cell. Following this, Polly and Molly were the first mammals to be simultaneously cloned and
The Marine Mammal Center no longer capable of fending for itself. Some animals may have suffered injuries that have left them blind or otherwise disabled. Although their health is stable, they may no longer be able to survive independently in the wild. These too, are considered unreleasable. In these circumstances, the Marine Mammal Center works with the National Oceanic and Atmospheric Administration (NOAA) and the National Marine Fisheries Service (NMFS) to find a permanent home for the animal in an approved zoo or aquarium. In May, 2011, the San Francisco Zoo accepted two such animals, both are male California sea lions; named Silent Knight