Countershading, or Thayer’s Law,'s a form of camouflage. Countershading, in which an animal’s pigmentation's darker dorsally,'s often thought to have an adaptive effect of reducing conspicuous shadows cast on the ventral region of an animal’s body. In essence the distribution of light on objects that're lit from above will cause unequal reflection of light on a solid body of uniform colour, such shadows could provide predators with visual cues to a prey's shape and projection.… (More on Countershading)