Climate change has caused a wild sheep species on a remote Scottish island to shrink in size, according to scientists. They believe that lambs do not need to put on as much weight because winters have become shorter and milder. The species, found on the unpopulated island of St Kilda, has been studied since 1985. Scientists believe the discovery is important as it illustrates how animals are adapting to changing temperatures. Several species of birds and fish have also altered in size, which could also be attributed to global warming.