Definitions for "Dawnsong"
A song that adult (ASY) male martins emit in flight high above their breeding sites during the pre-dawn hours of spring. It's adaptive function is thought to be the attraction of nocturnally migrating subadult (SY) males and females to the colony site. By attracting more colony members, a dawnsinging male theoretically increases his opportunity of engaging in forced extrapair copulation, and therefore leaving more offspring during a single summer's breeding effort.