Gigantism and acromegaly are two disorders with the same disease mechanism and somewhat similar presentations. Even though they have the same disease mechanism, the two have entirely different outcome simply due to the age of onset. Gigantism is the result if the disease mechanism starts in childhood.
Adult Velociraptors grew up to 6.8 feet (2 meters) long, 1.6 feet (0.5 meter) tall at the hip and weighed up to 33 pounds (15 kilograms).
Apatosaurus was one of the largest animals that ever lived. Some people believe the earth shook when this dino walked. It could grow to over 85 feet long and over 15 feet tall at the hips. Apatosaurus is known for its very long neck, which made it easier to eat greens from trees. They also had big feet: yard-long footprints (called trackways) from this big guy have been found in Colorado.