While some humans may find themselves struggling on the dancefloor, octopuses showcase an extraordinary ability to coordinate their eight flexible arms. These fascinating cephalopods perform a variety of behaviors, ranging from foraging to building dens and navigating the seafloor. Recent research has provided new insights into how octopuses manage their movements, revealing that, much like primates, rodents, and fish, they exhibit preferences for using specific limbs depending on the task at hand.
According to Kendra Buresch, a co-author of the study from the Marine Biological Laboratory in Woods Hole, Massachusetts, “In general, we did see that for most actions, the octopuses used their front arms more often than their back arms.” However, she also noted that there were exceptions to this pattern. The study, published in the journal Scientific Reports, marks the most comprehensive exploration of octopus movement behaviors to date.
The research team analyzed 25 one-minute video clips featuring 25 wild octopuses across three different species. These clips were recorded between 2007 and 2015 at six diverse locations, from Vigo in Spain to the Cayman Islands, each presenting unique habitats. For each video, researchers categorized the octopuses' behaviors, such as fetching objects or walking, and then identified the specific arm actions involved, including curling or extending the limbs away from their bodies.
The study delved into the four primary ways octopus arms can deform: shortening, elongating, bending, and twisting. Overall, the research identified 15 distinct octopus behaviors and 12 different arm actions. Some behaviors, such as crawling or performing a parachute attack, necessitated more complex arm movements compared to simpler actions like backward swimming. Remarkably, the researchers observed that multiple arm actions could occur simultaneously on the same or adjacent arms, demonstrating the octopuses' adaptability.
“This means that octopuses can be very flexible and adaptable in many different environments and tasks,” said Buresch. While the study did not indicate a preference for using their right or left arms, the researchers found that octopuses favored their front arms over their rear arms, with a usage split of 61% to 39% when considering all 12 actions together.
Further analysis revealed that octopuses utilized their front pair of arms more frequently for actions such as reaching, raising, lowering, and curling. Conversely, they preferred their rear pairs for stilt actions—where the body remains upright on the arms—and rolling actions that resemble a conveyor belt, both of which play a role in locomotion.
The findings from this study shed light on the intricate ways octopuses coordinate their eight arms to perform complex tasks and multitask effectively. The research not only enhances our understanding of octopus behavior but also holds potential applications beyond marine biology. “Such demonstrations of flexibility may help inform ethologists, sensory ecologists, neuroscientists, and engineers designing soft robotic appendages,” the researchers concluded.
This comprehensive study highlights the sophisticated motor skills of octopuses, making them a subject of ongoing interest for scientists and researchers in various fields.
