Scientists and the curious, 
have been paying attention to the songs of whales, especially to those of "Big Blue," the blue whale, since the 1960s. The blue whale, known to scientists as Balaenoptera musculus, a member of the baleen whale group, and the largest animal known to have existed on the Earth, ever. They were close to extinction, after years of over-hunting, and their future was seriously in doubt. But of late, there's been some good news.
Scientists Mark McDonald of WhaleAcoustics in Bellvue, Colo., John Hildebrand of Scripps Oceanography, and Sarah Mesnick of NOAA Fisheries Southwest Fisheries Science Center, haven been studying data regarding the songs of blue whales from around the world, and noticed a pattern. The pitch, that is the audio frequency of the songs, has been steadily curbing downward. Read more
