Many species produce individually specific vocalizations and sociality is a hypothesized driver of such individuality. Previous studies of how social variation influenced individuality focused on colonial or non-colon...Many species produce individually specific vocalizations and sociality is a hypothesized driver of such individuality. Previous studies of how social variation influenced individuality focused on colonial or non-colonial avian species, and how so- cial group size influenced individuality in sciurid rodents. Since sociality is an important driver of individuality, we expected that bird species that defend nesting territories in higher density neighborhoods should have more individually-distinctive calls than those that defend nesting territories in lower-density neighborhoods. We used Beecher＇s information statistic to quantify individu- ality, and we examined the relationship between bird density （calculated with point-counts） and vocal individuality on seven spe- cies of passerines. We found non-significant relationships between breeding bird density and vocal individuality whether regres- sions were fitted on species values, or on phylogenetically-independent contrast values. From these results, we infer that while in- dividuality may be explained by social factors, breeding bird density is unlikely to be generally important in driving the evolution of individually-specific vocalizations [Current Zoology 58 （5）： 765-772, 2012].展开更多
文摘Many species produce individually specific vocalizations and sociality is a hypothesized driver of such individuality. Previous studies of how social variation influenced individuality focused on colonial or non-colonial avian species, and how so- cial group size influenced individuality in sciurid rodents. Since sociality is an important driver of individuality, we expected that bird species that defend nesting territories in higher density neighborhoods should have more individually-distinctive calls than those that defend nesting territories in lower-density neighborhoods. We used Beecher＇s information statistic to quantify individu- ality, and we examined the relationship between bird density （calculated with point-counts） and vocal individuality on seven spe- cies of passerines. We found non-significant relationships between breeding bird density and vocal individuality whether regres- sions were fitted on species values, or on phylogenetically-independent contrast values. From these results, we infer that while in- dividuality may be explained by social factors, breeding bird density is unlikely to be generally important in driving the evolution of individually-specific vocalizations [Current Zoology 58 （5）： 765-772, 2012].
