As an increasing number of shadows passes, more flies (small dots) disperse from the central food patch (dark spot).CELL PRESS; WILLIAM T. GIBSON, DAVID J. ANDERSON
When prodded with a scary stimulus, fruit flies display some of the same fear-like reactions that humans do, according to a study published this week (May 14) in Current Biology.
Because emotion is difficult, if not impossible, to study directly in nonhuman animals, researchers at Caltech proposed breaking down emotional responses such as fear or anxiety into a set of behaviors known as “emotion primitives.” When a person is afraid of a spider, for example, he or she experiences a lasting negative feeling, an emotion primitive known as “persistence.” The more of the scary stimulus spiders there are, the more afraid the person will be, a primitive dubbed “scalability.” A third primitive, “context generalization,” occurs when the fear is strong enough to distract the person ...