More Than One Tool Some animals use more than one tool. Striated herons in Japan use a variety of tools when they go fishing. Live insects, berries, twigs, and even discarded crackers are bait. A heron crouches low over the water and
casts in its bait. T en it waits for a hungry fish to nibble the bait. When a fish is in sight, the heron lunges forward, snatches the fish, and gobbles it up. Other animals use simple tools in complex
ways. New Caledonian crows living in the South Pacific can use several tools to reach a goal. For example, a crow might bend a stick to create a hook. It uses the hook to snag a certain type of leaf. It trims the leaf with its beak to make a sharp spear. Now the crow can hunt insects with its spear. T is unique behavior shows a higher level of thinking. Scientists also observed that crows make
leſt -handed or right-handed tools for themselves. Many of the New Caledonian crows appear to be right-handed. Most of the crows had a preference for making tools from the leſt edge of a leaf—a process that favors use of the right eye and right side of the beak.
The Right Tool for the Job Tool use isn’t just found among birds. Many marine animals use tools, too. Dolphins spend more time hunting with tools than almost any other animal besides humans. A pod of bottlenose dolphins in Australia surprised some scientists one day with their tool use. T e dolphins tore off pieces of sponge from
the sea bottom. T ey gripped the sponges in their beaked mouths. T en they stirred their noses in the rough rocks. T ey were searching for hidden fish to eat. T e soſt sponges protected their noses from the rough rocks. Sea otters also use tools to get food. T ey
love to eat a shellfish called abalone. But it can be tough to open the shells. So, a sea otter will balance an abalone shell on its stomach. Using a small stone, the otter will hammer the shell. Eventually, the shell will crack, and the otter will have its meal. Stones aren’t the only tool sea otters use.
T ey also use seaweed. Before napping, a sea otter might wrap kelp or other seaweed around its body. T is anchors it in place while it sleeps.
A sponge held on a dolphin’s beak protects its skin from the rough rocks on the seafl oor.
Body Armor T e veined octopus makes tools out of what it can find in the ocean. T is might be a seashell or even a coconut shell. T e octopus stacks the shells on either side of its body, like a suit of armor. Now a predator will have a hard time attacking it. To move, the octopus makes its arm
rigid like stilts. T en it walks across the seafloor while holding the shells against its body. T e instinct to protect itself is inherited. Yet the way this octopus uses these tools is a learned behavior. It finds the best tool to protect itself. T at’s pretty good defense. But there’s one octopus, called the
blanket octopus who plays off ense. When it feels threatened, it tears off tentacles from a jellyfish. T en, if attacked, it wields them as a weapon.
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