You kind of expect the environment, ecology etc. shape the signal evolution. The reasons behind the signal evolution in diversification is difficult to pin-poin

You kind of expect the environment, ecology etc. shape the signal evolution. The reasons behind the signal evolution in diversification is difficult to pin-point. One interesting thing from paper: "We show that origins of acoustic communication are significantly associated with nocturnal activity." > Acoustic communication also appears to have been secondarily lost in several mammals and frogs (but not in birds) For birds, they have their fitness closed tied to vocal communication. We're studying song birds and perception of songs. It's really interesting how sensitive the perception of song is. Even slight change in frequency or note can change the response of bird.