Dogs have a sense of the basic way objects should behave, according to scientists, who say they stare longer if a computer animation breaks the laws of physics. Humans use a process known as'contact causality' from an early age to make sense of the physical environment, but little is known about the processes that non-primate animals use to make sense of the world and how things work. To better understand this in dogs, a team at the University of Veterinary Medicine, Vienna, adapted an eye tracking system used on human infants. Dogs were presented with realistic 3D animations of balls that obey and break Newton's basic laws of physics, and tracked their pupil dilation and attention span. The animals tracked the movements of balls closely throughout the study, but pupils were larger when objects in the animations broke the laws of physics.