Final answer:
The symmetry seen in swiftly moving animals is bilateral symmetry, which allows for directional and streamlined motion, facilitating rapid movement.
Step-by-step explanation:
The symmetry found in animals that move swiftly is bilateral symmetry. Animals with bilateral symmetry, such as butterflies and humans, can be divided into mirror-image halves only by a single plane through the midline.
This type of symmetry allows for streamlined and directional motion, which suits rapid movement and active lifestyles, as seen in land-based and aquatic animals capable of high-speed locomotion.