In the absence of eyes, the fresh water polyp, Hydra magnipapillata, nevertheless reacts to light. They are diurnal, hunting during the day, and are known to move, looping end over end, or contract, ...

What good is half an eye? Evolutionary biologists studying the origins of vision get that question a lot, and new research points to a possible answer. New findings indicate that, even in the absence ...

Left, a hydra stained in blue where the light-sensitive opsin gene is expressed. Right, two tentacle bulbs showing the arrangement of neurons and stinging cells (red), muscle fibers (green) and cell ...

(Santa Barbara, Calif.) –– What good is half an eye? Evolutionary biologists studying the origins of vision get that question a lot, and new research out of UC Santa Barbara points to a possible ...

A small clarification, dear reader: in a recent post about the fantastic stinging cells of the Cnidaria (jellyfish and their relatives), it was stated that only cnidarians possess these cnidocytes. It ...