Different colour-shifting displays and behaviour patterns are two of the ways in which both female and male octopuses appear to often communicate with each other, according to a new study.
The unusual octopus behaviour was first spotted by a diver in Jervis Bay, Australia. To decipher the mysterious language of the octopuses, researchers captured and then analysed 52 hour of footage of an octopus species called Octopus tetricus, also known as Sydney Octopus or Gloomy Octopus.
David Scheel, the study’s first author and a professor of marine biology at Alaska Pacific University, said that previous studies also found that some octopuses use various signals and displays to woo a potential partner. However, the new study is the first one to specifically focus on signalling between octopuses, Scheel stated.
For the study – published Thursday (Jan. 28) in the online journal Current Biology – the researchers looked at 52 hours of recorded footage. Each day, three to ten octopuses would appear at the site, and the footage showed a total of over seven hours of octopus interactions.
There were 512 instances of physical movements – like reaching toward each other – and 345 examples of changing colours, the researchers found. Reaching comprised about 72 percent of all physical interactions, making it the most frequent and common interplays.
Researchers also observed a frequent posture in which an octopus would ‘stand tall’. When standing tall, the octopus would also display a dark colour – which in combination with the posture likely signified aggression toward another octopus, the researchers explained. On the other end of the spectrum, when an octopus displayed a paler colour it meant that it was ready to retreat.
According to Scheel, one of the most surprising things caught on camera was that the octopuses would use a piece of flotsam (floating wreckage of a ship or its cargo) to perform the ‘stand tall’ posture.
Further researchers shall look more into the context of signalling between octopuses – in which females interacted with males, females interacted with females, males interacted with males, and males interacted with females – to see whether it is in fact part of a complex mating system, Scheel and his colleagues noted.
Image Source: The Daily Sheeple