These sunbirds keep singin' their song (VIDEO) University of California - Berkeley This video is under embargo. Please login to access this video. To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Caption Sky-island populations of East African double-collared sunbirds have been isolated from one another for hundreds of thousands if not a million years, but still look very similar. While almost indistinguishable in plumage, however, some of these bird lineages have altered their songs a lot while others have not — their songs differ little from the songs of related populations they’ve not encountered for millennia. Credit Video by Roxanne Makasdjian and Alan Toth, UC Berkeley; audio courtesy of Jay McEntee, Missouri State University; sunbird video clip courtesy of Oliver Fowler Usage Restrictions Sunbird video clip cannot be used without authorization of Oliver Fowler License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.