The cuttlefish ranges in size from about 3 inches (8 centimeters) to about 5 feet (1.5 meters) long. Its oval body is commonly brown with crossbands and purple spots. It is brilliantly metallic in the sunlight and often changes color. The cuttlefish's body is surrounded with a frilled fin.
Night is dangerous for giant Australian cuttlefish. They live in rock reefs and are known to dive to the depths of the nearby sea grass to avoid being eaten. For years scientists have studied the beautiful colors that these animals (these cephalopods are kindred to the squid and octopus) can turn. However, until now they have only studied them during daytime.
Technology has improved enough to allow these scientists to study them at night using a Remotely Operated Vehicle (ROV) with a video camera attached. What they are discovering is cuttlefish DO change color at night too! The reason postulated is that their predators have good night vision and can find them, and that the night vision and color adaptation skills of the cuttlefish are good enough to keep themselves hidden in plain sight.
Because visual predation in the world under the ocean at night has not been studied, scientists are excited to be discovering information from the other half of the daily cycle of life – at least in the Australian cuttlefish.
The above picture and definition are from the World book Encyclopedia which you and your students can locate at the State Library of Kansas site http://kslc.org/ . You can also find cuttlefish articles in SIRS, Thomson-Gale (InfoTrac) which includes the article by Roger Hanlon, et al Adaptable Night Camouflage by Cuttlefish from The American Naturalist vol. 169:4 (April 2007) that inspired this entry, and from ProQuest.
Technology has improved enough to allow these scientists to study them at night using a Remotely Operated Vehicle (ROV) with a video camera attached. What they are discovering is cuttlefish DO change color at night too! The reason postulated is that their predators have good night vision and can find them, and that the night vision and color adaptation skills of the cuttlefish are good enough to keep themselves hidden in plain sight.
Because visual predation in the world under the ocean at night has not been studied, scientists are excited to be discovering information from the other half of the daily cycle of life – at least in the Australian cuttlefish.
The above picture and definition are from the World book Encyclopedia which you and your students can locate at the State Library of Kansas site http://kslc.org/ . You can also find cuttlefish articles in SIRS, Thomson-Gale (InfoTrac) which includes the article by Roger Hanlon, et al Adaptable Night Camouflage by Cuttlefish from The American Naturalist vol. 169:4 (April 2007) that inspired this entry, and from ProQuest.
