Associations between sensory development and ecology in three species of clupeoid fish
Sensory development was examined in larvae of three species of clupeoid fish, Atlantic menhaden (Brevoortia tyrannus, Clupeidae), scaled sardine (Harengula jaguana, Clupeidae), and bay anchovy (Anchoa mitchilli, Engraulidae). Differences in habitats occupied by these species allowed the testing of hypotheses relating timing of sensory ontogeny to habitat shifts in fish larvae. Migration of menhaden from offshore to estuarine waters coincided with, or was preceded by, auditory bulla inflation, development of rod photoreceptors, onset of retinal summation, improvements in visual acuity, and formation of cephalic lateral-line canals. Examination of developmental patterns in sardine and anchovy larvae, both of which live inshore throughout the larval period, showed that some of these associations between habitat and sensory morphology were adaptive and some coincidental. Inflation of the auditory bullae occurred earlier in the larval period in anchovy than in menhaden. Specializations for enhanced visual sensitivity occurred earliest in anchovy but were not different between sardine and menhaden. There was no correspondence between habitat and visual acuity or lateral-line development. Thus, ontogeny of auditory bulla inflation and retinal sensitivity may coincide with habitat shifts, at least at the family level, but lateral-line development is more constrained by phylogeny than adapted to ecology.
Higgs, Dennis M. and Fuiman Copeia, Lee A., "Associations between sensory development and ecology in three species of clupeoid fish" (1998). Copeia, 1998, 1, 133-144.