The Most Amazing Structure on Earth There are people who say the most amazing structure on earth is the human brain. It is so complex that it took about 700 million years to develop. Humans started out as wormlike creatures that used one end of the body to move forward. Ever so slowly, a bunch of nerves began developing at that one end — the head. These nerves helped the creature to sense light, food and danger. Eventually, this bunch of nerves became the creature’s brain. To carry messages from the brain to other parts of the body, the creature grew a spinal cord. Later, the creature became a fish with eyes, ears and a nose that could send the brain information about sights, sounds and smells. More time passed, and the fish grew arms and legs so it could move about on land. For this, it needed a larger and more complex brain. It became an ape-like creature, and the parts of the brain used for seeing images and being social grew much stronger. Finally, the ape-like creature became h...