Another segment from 'Cosmos.' Sagan discusses the fascinating ability whales have to eloquently communicate with each other over long distances with sound. He also discusses the effects human seafaring have had on them, both in terms of threatening their lives and disrupting their communicative networks with their noisy vessels. He even tries his hand at singing a little whale-song! Ultimately, though, he makes a very good point: for all the excitement people have about intelligent life from other planets, we really need to do a better job of relating to our fellow intelligent animals here on earth.