A stray dog adopted from Texas has turned into a devoted concert audience for his musician owners in Vancouver — a feel-good story with a small scientific backing.

• Billy was found as a stray in Texas and adopted four years ago by Teresa and Luchi, two professional musicians.
• He now asks for music himself, crying when the playing stops until they start again.
• Recorded music does not satisfy him — he wants live performance, especially piano, cello, or double bass.
• His owners say playing for him is easier than playing for people, because he listens without judging.
• Animals responding well to live music is a known effect, seen in zoo performances too.

Outlook: Billy is starting to attend other musicians' performances, so his concert habit looks set to grow.