Dogs frequently run behind moving vehicles due to innate behaviour which is linked to their prey drive which means the movement of a vehicle awakens their innate chasing tendencies, which are similar to pursuing smaller animals. Furthermore, some dogs may perceive cars as possible playmates or sources of excitement, connecting their movement with pleasure. Some dogs chase vehicles out of fear or anxiety, as they perceive a threat. Finally, dogs may simply be intrigued about their surroundings, reacting to the sounds and movements of nearby cars.