Complex sentence: A nearby eccentric "Styracosaurus" (Peter Sohn), also impressed with the caveboy's physical prowess, tries to give him a name, but when Arlo calls him "Spot," he responds to it.
Split into simpler sentences: A nearby eccentric "Styracosaurus" (Peter Sohn), also impressed with the caveboy's physical prowess, tries to give him a name. But when Arlo calls him "Spot," he responds to it.