Chorus, the home planet of the Jade Chime Singers, has a thick atmosphere, but has a gravity level greater than Earth-standard; for this reason flying organisms on Chorus need almost as much wing per body mass as an Earth organism.
Flitterhounds evolved from a flightless animal as large as a big dog. The smallest flitterhounds are a little larger than a mouse, while the largest have hollow bones and large wingspans; here are some of the more common species.