Octopuses give eight thumbs up for high-def TV — sort of:
[Macquarie University marine biology researcher Renata Pronk] collected 32 common Sydney, or gloomy, octopuses from Chowder Bay, near Mosman, and showed them a series of three-minute videos screened on a monitor in front of their tank.One video featured a crab, an octopus delicacy.
A second starred another octopus, while a third had a “novel object” they would not have seen: a plastic bottle swinging on a string.
Miss Pronk then watched each octopus for any consistent response pattern, such as boldness or aggression.
When the crab movie was screened “they jetted straight over to the monitor and tried to attack it”, she said, adding that was strong evidence they knew they were watching food.
When the octopus movie was screened some became aggressive while others changed their skin camouflage or “would go and hide in a corner, moving as far away as possible”.
On viewing the swinging bottle, some puffed themselves up, just in case the object was a threat, while others paid no attention.
But significantly, when the experiment was repeated over several days, she found no consistent response from any octopus. Such random responses implied octopuses have no individual personalities.
She suspected previous efforts to show movies to octopuses failed because their sophisticated eyes were too fast for the 24-frame per second format of standard-definition video.
“They would have seen it as a series of still pictures,” said Miss Pronk, who had success using high-definition, operating at 50 frames per second.