There are more examples of ‘tool use’ in the animal kingdom than you can shake a stick at. And what do we mean when we refer to animals using tools? Tool use involves manipulating an object to improve the “form, position, or condition of another object, another organism, or the user itself.” Examples include capuchin monkeys using stones to crack open nuts, crows using twigs to fish insects out of logs, or alligators balancing sticks on their snouts to attract birds (which they gobble up).
Nature documentary fans have probably seen footage of ocean animals using tools as well, like dolphins that use marine sponges to protect their beaks when digging in the sand, or sea otters that crack open clams with rocks. But tool use in the ocean is not restricted to brainy mammals like dolphins, or even vertebrates. Here’s a list of six tool-using ocean animals that a recent scientific review turned up, some of which might surprise you …
The green sea urchin uses leaves, shells, and other material to cover its body in order to prevent sunburn.
Boxer crabs carry sea anemones in their claws, which they use as weapons to fend off enemies. Elsewhere in the crab family, grey hermit crabs place sea anemones on their shells to help balance out the shell’s weight, making it easier for them to walk. Many crab species carry or cover themselves in objects like algae, sea anemones or shells, which they use as camouflage or predator defence.
The veined octopus carries coconut shells, awkwardly dragging them as it walks along the seafloor. When threatened by a predator, it hides itsef in the shell, using it as a kind of armour.
Some species of squid – like the adorable stubby squid – will use jets of water to blast an indentation in the sand, creating the perfect hiding place. After plopping themselves down in their new hidey-hole, the squid use their dexterous arms to throw sand over their bodies, with only their eyes protruding (see the below above) to look out for approaching danger.
Individuals or groups of humpback whales will dive down under a shoal of fish and release bubbles from their blowholes as they swim in complex spiral patterns. This creates a wall of bubbles called a ‘bubble net’ that encircles prey, making them easy targets as the whales then lunge upwards with their mouths agape. *Skip ahead to 0:55 in the video for the humpback bubble-netting action.
Some species of sea snails will use stones to help right themselves after falling over. When flipped on its back, the snail will grab nearby stones, moving them along its ‘foot’ until enough stones have accumulated on one end to help the snail flip itself over.
This post was written for and originally appeared over at Earth Touch.