VISUAL TRACKING OF BLUE BIOLUMINESCENCE-LIKE LIGHT-SOURCES BY HYPERIID AMPHIPODS

Hyperiid amphipods (Brachyscelus, Phrosina, Phronima) possess complex compound eyes, often split into dorsal and ventral parts. They are goo d swimmers and in the experiments performed here use whole body moveme nts to track a moving LED by rotation and translation. These tracking movements attempt to keep the image of the LED in the antero-dorsal pa rt of the field of view, which corresponds to the upper part of the re tina of the ventral eye, not the specialised dorsal eye. We believe th is response is normally concerned with attraction to and pursuit of lu minescent gelatinous organisms upon which hyperiids are highly dependa nt.