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Billions of insects are moving together over the sky like a black cloud. It's a swarm of locusts. Many insects move in huge swarms. They form swarms for different reasons. Some move together to look for food or to find new homes. Sometimes insects swarm for protection. These enormous swarms can destroy food crops and harm other living things.
When something disturbs a red fire ants' nest, out they will come. Not just one or two, but thousands of them. The fire ants swarm all over their victim. Their stings burn like fire. Each ant in the swarm can sting over and over again. The fire ants hold onto their victim with their mouth parts. Then they inject their prey with poison. Most small animals cannot survive the stings from a swarm of fire ants.
When army ants are on the move, anything in their path is prey. Even snakes can' t escape a swarm of these stinging ants. Army ants move together to look for food. They can't see their prey, but they use smells and sounds to find their way. If they come to a river, they make a bridge with their bodies. They cling together with their legs. Then the rest of the ants can cross the bridge. There is not much that can stop these fierce and cruel ants from chasing their prey.
Insects are not the only animals that swarm. There are many others that do. Most are not harmful to people. Being close to a huge swarm of animals can be scary and dangerous. Some scientists have studied animal swarms. They have found that many swarms follow simple rules. They work together to solve problems. When they work together they are a very strong team.
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