How to use 8 arms? Octopuses tend to explore with their front limbs

Washington – Humans can be right -handed or left -handed. It turns out that the octopuses do not have dominant arms, but they tend to do tasks more often with their front arms, according to new research.

Scientists studied a series of short videos of rampant wild octopuses, swimming, standing up, recovery and trial and error – among other current activities – to analyze how each of the eight arms moved.

“All arms can do it all – it’s really incredible,” said the co -author and marine biologist Roger Hanlon of the Marine Biological Laboratory in Woods Hole, Massachusetts.

The members of the octopus do not specialize as many members of mammals. However, the three species of octopus in the study showed a clear preference to use their four front arms, which they did around 60% of the time. The rear arms were used more frequently to trample it and the bearing which help to advance the octopus.

“The front arms make most of the exploration, the rear arms are mainly intended to walk,” said Mike Vecchione, a zoologist of the Smithsonian National Museum of Natural History who was not involved in the study.

The researchers analyzed the video clips taken between 2007 and 2015 in the Atlantic Ocean and the Caribbean Sea. It was the first major study to examine specific actions of members in the wild.

Unlike previous research on the behavior of octopuses in the laboratory, the new works have shown that the octopuses did not show any preference for the right or left arms in their natural environment.

The results were published Thursday in scientific reports.

“I am impressed by the researchers who have managed to do so,” said Janet Voight, octopus biologist at the Field Museum of Natural History in Chicago, who had no role in the study.

The octopuses are shy and elusive creatures. The species studied spend most of their time hidden in dens – which means that filming them required patience and perseverance for many years.

The members of the octopus are complex – used for mobility and environmental detection. Each arm contains between 100 and 200 suction cups – complex sensory organs “equivalent to human nose, lips and tongue,” said Hanlon.

If an arm is bitten by a predator, as often happens in nature, the octopus have several backups.

“When you have eight arms and they are all capable,” said Hanlon, “there is a lot of redundancy.”

___

The Department of Health and Sciences of the Associated Press receives the support of the Department of Science Education from Howard Hughes Medical Institute and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.