Zoli and Sungai, a pair of Siamangs, are credited with singing the duets that fill the air. Now that they are becoming young adults, their duets are becoming a love songs.
"It's a long song. They sing, back and forth and together," said the Louisville Zoo's Assistant Director Steven Taylor. "We think it helps cement the relationship of the pair and it also helps tell other Siamangs where they are."
Copyright 2016 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.