Fish use a special organ called a lateral line to swim in perfect sync without looking at each other.

The lateral line is a row of small holes running along the side of a fish from its head to its tail. Inside these holes are sensory organs called neuromasts. These organs contain tiny hairs inside a jelly-like cap. When water moves, it bends these hairs and sends signals to the fish's brain about the water's speed and direction.Research shows that this system works incredibly fast. Fish in a school can react to their neighbors in less than 50 milliseconds. This is much faster than a human can blink. This quick reaction time allows the whole group to move together like a single large animal.Swimming in a school also saves energy. Fish can 'surf' on the water currents created by the fish in front of them. This can reduce the effort needed to swim by up to 20%. It also helps them stay safe from predators.If one fish on the edge of the group feels a predator nearby, the pressure change travels through the water. Every fish in the school feels this change almost at the same time. This triggers a group escape move that confuses the predator. Even blind fish can use this system to navigate and stay with their group.