The first ever cloned mammal, Dolly, has died. The Roslin Institute, a Scottish research centre created Dolly, the cloned sheep. Dolly died from a very bad lung disease. Dolly was created from a single cell of another sheep and was born on July 5^th, 1996. Dolly first fell ill with arthritis, a bone disease that usually affects animals older then Dolly was. Scientists are trying to find out if Dolly was infected at an earlier age because she was a clone.