Writing and Reading

      The album Songs of the Humpback Whale was produced in 1970 by bio-acoustician Roger Payne, based on recordings of the elaborate vocalizations of several humpbacks. The use of underwater microphones, called hydrophones, showed that not only can whales communicate, but they do so with beauty and complexity. The haunting sounds on Songs of the Humpback Whale, along with Payne’s liner notes for CRM Records, helped turn the tide of US public opinion against whaling.
     In addition to having aesthetic and political significance, the album can also be considered historically valuable. Whales change their songs over time, so these recordings document a cetacean performance practice of a time gone by. . . 

The writer wants a transition that makes a connection to the main topic of the previous paragraph. Which choice best accomplishes this goal?