Alex Mustard/NPL/Minden Pictures
Making Moves
Deep beneath the sea, an octopus stretches its eight arms and glides across the rocky floor. Suddenly, it spots a crab moving nearby. Balancing on the tips of its arms, the octopus creeps closer. In one lightning-fast motion, it grabs the crab and pulls it close. Got it!
Scientists now have names for each of those moves. They’re all listed in the world’s first octopus dictionary, which was released in September.
Magical Motions
Marine biologist Chelsea Bennice was part of a team that wanted to understand exactly how octopuses use their arms to explore and hunt. Octopuses don’t have bones. Their limbs are made of muscle, which allows them to bend, stretch, and twist in every direction.
“There’s no other animal that’s capable of this extreme arm flexibility and control,” Bennice explains.
For the dictionary project, divers filmed 25 octopuses in six habitats, including off the coasts of Spain and South Florida. After years of closely studying the footage, the scientists identified 12 basic arm actions and 15 behaviors.
“They often use their front arms for exploring and back arms for locomotion,” Bennice says.
The scientists’ research isn’t just for making a dictionary. It’s also being used to design soft robots that can squish into tight spaces, like octopuses do.
“We do this research to discover more about the animal but also to help other fields,” Bennice says.
1. What is the “octopus dictionary” described in the article?
2. What is the meaning of locomotion? Describe an example of octopus locomotion.
3. According to the article, what is one practical application of the scientists’ research?
