Sclera other species share, but also to the fact that the human iris is relatively small and comprises a significantly smaller portion of the exposed eye surface compared to other animals. It is theorized that this adaptation evolved because of our social nature as the eye became a useful communication tool in addition to a sensory organ. It is believed that the conspicuous sclera of the human eye makes it easier for one individual to infer where another individual is looking, increasing the efficacy of this particular form of nonverbal communication. Animal researchers have also found that, in the course of
The Human Factor (2002 The Outer Limits) The Human Factor (2002 The Outer Limits) "The Human Factor" is an episode of the television show "The Outer Limits". It first aired January 11, 2002, in the show's seventh season. This episode is a clip show. Clips appear from the following episodes: "Phobos Rising", "Hearts and Minds", "Manifest Destiny", "Something About Harry", "The Haven", "Final Exam", "Final Appeal", "The Vaccine", and "Replica". Jupiter's moon Ganymede is now the only hope for the human race in 2084 as overpopulation and constant warring has left much of Earth uninhabitable. Space Commander Ellis Ward (Robert Duncan McNeill) must convince android assistant Link