The stream-lined shape of fishes is an adaptation for

The streamlined shape of fishes is an adaptation for easy movement through water. The long and narrow body of fishes reduces water resistance, making it easier for them to swim and move quickly through the water. This shape also allows them to make quick turns and changes in direction, which helps them escape from predators and catch their prey. Additionally, the streamlined shape reduces the amount of energy required for swimming, allowing fishes to swim for longer periods without getting tired. Therefore, the streamlined shape of fishes is primarily an adaptation for efficient swimming and movement in their aquatic environment.