A study has found that a bird listening to birdsong may experience some of the same emotions as a human listening to music.
A study of white-throated sparrows by the Emory University found the same area of the bird's brain was triggered when female birds listened to male birdsong when they were in a breeding state, the Daily Mail reported.
However, male birds listening to another male's song had a response similar to that of people when they hear extremely unpleasant music in a horror film, the study said.
The research is published in Frontiers of Evolutionary Neuroscience.
Sarah Earp, from Emory University, said: "Scientists since the time of Darwin have wondered whether birdsong and music may serve similar purposes, or have the same evolutionary precursors."
The research came about following a lecture. During a class, a guest speaker who was a composer said he thought birdsong was like music, but one lecturer thought it was not.
Some birds were treated with hormones, to push them into the breeding state, while a control group had low levels of estradiol and testosterone.
During the non-breeding season, both sexes of sparrows use song to establish and maintain dominance in relationships.
During the breeding season, however, a male singing to a female is almost certainly courting her, while a male singing to another male is challenging an interloper.
"The neural response to birdsong appears to depend on social context, which can be the case with humans as well," Earp said.
"Both birdsong and music elicit responses not only in brain regions associated directly with reward, but also in interconnected regions that are thought to regulate emotion," she was quoted as saying.