How did the Grants test their hypothesis that differences in

Last updated: 7/30/2022

How did the Grants test their hypothesis that differences in birds' songs can keep finches from breeding with members of other species? They played the song of the medium ground finch to medium ground finch males through a loudspeaker to see if they would respond; they then played the song of the cactus finch to cactus finch males to see if they would respond. They played the songs of medium ground finches and cactus finches through a loudspeaker at different times, when individuals from both species were present, to see which species responded to each song. They recorded birds singing on the island of Daphne Major for an entire breeding season to see which type of song was used more often by each species. They watched which birds were mating with each other and listened for the songs the birds were singing.