The Nervous System.

Abstract

Polar fishes feed, grow, and reproduce at low temperature, making them an important model for understanding temperature adaptation. Other fish may survive cold winters, but polar fish conduct their entire life cycle in frigid water. This chapter discusses the physiology or function of the nervous system and the sensory organs of polar fishes. It addresses the issue of temperature adaptation in the nervous system and discusses what is special about the neurophysiology of fish from stenothermal arctic and antarctic environments, what themes are common to both groups, and how the polar species differ from fishes that are more eurythermal yet can acclimatize to severe cold. The extent to which antarctic fish have optimized their critical cellular and neural systems to operate at subzero temperatures is reflected in their extreme stenothermy. This chapter discusses antarctic species rather than arctic species.