Ten different “ecotypes” of killer whales have now been proposed ... more grey than black and with a much larger white eye patch than types A or D. And from satellite tracking studies ...

They are found on every continent and in every ocean, and range in size from tiny bumblebee bats to enormous blue whales. One reason for their success is the way they move. Mammals as a group use ...

just as human language emerges from the different vocal sounds we combine to form words and sentences. The whales shape these codas into some 300 types by varying their duration, rhythm and tempo ...