The impact of evolving migratory behavior on brain organization in birds has been a foundational question in the emerging field of neuroecology. One generalization that seems to be approaching consensus is that migratory species/populations have smaller brain volumes than their nonmigratory comparison groups. The lark sparrow (Chondestes grammacus) is a North American species characterized by migratory and nonmigratory populations. Consistent with what has been observed in other species/population comparisons, we found that, relative to body weight, migratory females from Nebraska have smaller brain volumes than nonmigratory females from Texas. We also carried out an exploratory, higher-order analysis of possible differences in the volumes of a number of telencephalic subdivisions. Although our small sample size precluded statistical verification of any difference, noteworthy was that, although there seemed to be no indication of a difference in the relative hippocampal volume between the two populations, the migratory birds from Nebraska showed a clear trend toward a smaller nidopallium. The importance of higher-resolution, brain subdivisional analyses has been discussed.
aDepartment. of Ecology & Evolution, University of Salzburg, Salzburg, Austria
bDepartment of Psychology, J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University, Bowling Green, Ohio
cSutton Avian Research Center, Oklahoma Biological Survey, University of Oklahoma, Bartlesville, Oklahoma, USA
Correspondence to Roman Fuchs, Department of Ecology and Evolution, Neurosignaling and Neuroecology Unit, University of Salzburg, Hellbrunnerstr. 34, 5020 Salzburg, Austria Tel: +43 662 8044 5634; e-mail: firstname.lastname@example.org
Received June 26, 2015
Accepted September 4, 2015