Authors marked in bold are EvolEcol members.
Vincze O, Vágási CI, Pap PL, Osváth G and Møller AP 2015. Brain regions associated with visual cues are important for bird migration. Biology Letters (in press).
Abstract: Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from 6 continents, we show that the sizes of both the telencephalon and the whole brain decreases, and the relative size of the optic lobe increases, while cerebellum size does not change with increasing migration distance. Body mass, whole brain size, optic lobe size and wing aspect ratio together account for a remarkable 46% of interspecific variation in average migration distance across bird species. These results indicate that visual acuity might be a primary neural adaptation to the ecological challenge of migration.
Keywords: brain mass, cerebellum, migration distance, neuroecology, optic lobe, telencephalon
Image source: http://people.eku.edu/ritchisong/birdbrain.html