rivermusic:

Cover Photo — September 18, 2007, 104 (38)
"Mountain bluebird (Sialia currucoides, male) in flight. Aggressive and dispersive behavior in western bluebird males enabled the species to recolonize its historical range across the northwestern United States over the past 30 years, at the expense of mountain bluebirds. Once western bluebird colonies were reestablished, natural selection quickly reduced aggression. See the article by Duckworth and Badyaev on pages 15017–15022. Photo courtesy of Alex Badyaev".

rivermusic:

Cover Photo — September 18, 2007, 104 (38)

"Mountain bluebird (Sialia currucoides, male) in flight. Aggressive and dispersive behavior in western bluebird males enabled the species to recolonize its historical range across the northwestern United States over the past 30 years, at the expense of mountain bluebirds. Once western bluebird colonies were reestablished, natural selection quickly reduced aggression. See the article by Duckworth and Badyaev on pages 15017–15022. Photo courtesy of Alex Badyaev".