Tufted titmouse
Chapter 6: Song Learning Often Creates Complex Songs and Large Repertoires
Subchapter: Small to large repertoires
From page 87 in the book.
♫391. Two different songs from a male. May 1, 2012. Story, Indiana. (1:17)
♫392. Again, two different songs, but hear how, beginning at 0:05, the male in the background matches the male in the foreground. May 15, 2010. Yorktown National Battlefield, Yorktown, Virginia. (1:21)