Relationship between brain morphology and ecology in New Zealand Galaxiidae, particularly Galaxias vulgaris (Pisces: Salmoniformes)

Size‐related changes in the relative proportions of the forebrain, optic lobes, and cerebellum occur in Galaxias vulgaris Stokell. The relative increase in size of the forebrain and reduction in size of the optic lobes are associated with a change from the free‐swimming existence of recently hatched fish to the cryptic habits of adults. The relative increase in size of the cerebellum is associated with a move from quiet waters to riffles. Dorsal brain patterns of juvenile and adult G. vulgaris, Galaxias maculatus (Jenyns), and Neochanna burrowsius (Phillipps) are compared and related to the known ecology of these species. Inferences are drawn on the ecology of the less well known Galaxiidae by comparing their dorsal brain patterns with those of G. vulgaris, G. maculatus , and N. burrowsius .