If we were single-celled organisms with one photoreceptor only sensitive to light and dark, the fight-or-flight response would be simple – we’d flee or stick around when something obstructed our light (i.e. cast a shadow and implied a possible larger single- or multi-celled predator). As more complex animals, our fight-or-flight response isn’t strictly light-sensitive and gets influenced by things like past experiences, present thoughts, and emotions. Since we’re lucky enough