Primal Human Ability

Pareidolia is a phenomenon wherein people perceive likenesses on random images—such as faces, animals, or objects in clouds, trees, and rock formations because the brain tries to assign meaning to what it encounters when it can.

According to Psychology Today, this phenomenon is due to the fusiform gyrus in the temporal lobe of the cortex that activates a process for facial recognition. In addition, the tendency for this recognition is an evolutionary byproduct because ancient man was better off quickly recognizing if a face was a familiar friend or an unfamiliar foe.

Cognitive processes are activated by the "face-like" object which alerts the observer to both the emotional state and identity of the subject, even before the conscious mind begins to process or even receive the information. A "stick figure face", despite its simplicity, can convey mood information, and be drawn to indicate emotions such as happiness or anger. This robust and subtle capability is hypothesized to be the result of natural selection favoring people most able to quickly identify the mental state, for example, of threatening people, thus providing the individual an opportunity to flee pre-emptively. 

Since the dawn of man, the primal human brain has been recognizing faces in nature and continues this primal human ability in modern times.