Cover image
Cover The elephant shark, Callorhinchus milii, a deep-sea cartilaginous fish belonging to the subclass Holocephali or chimaeras. In this issue, the presence of cone visual pigments in the elephant shark is demonstrated, indicating the potential for trichromatic color vision, which is unusual for a deep-sea fish, with important implications for the evolution of the vertebrate visual system. (Photo: Kelvin Aitken, marinethemes.com. [For details, see Davies et al., pp. 415–426.])
