As humans, we like to think that we occupy a special place within the animal kingdom, and we’re often surprised when we see other animals expressing humanlike qualities. Even our closest living relatives—other primates—impress us by using basic tools or expressing emotions. But if we profiled our commonalities with other species in detail, we might be less likely to harbor exaggerated perceptions of human superiority. The best way to dispel illusions about what it means to be human is to compare our behaviors to the behaviors of the simplest animals we can find — including Drosophila, also known as humble fruit fly.
There’s one particular behavioral question that unites many animal species: “Should I explore the wider environment or exploit my current environment?”
For most animals, the question relates to whether they should remain in a familiar location, where they understand the availability of food and risks from predators, or explore entirely new and potentially dangerous environments in order to improve their options. For humans in the developed world—unlike for many animals—the question usually lacks fatal consequences. But it can still apply to the most important decisions in our lives, like whether I should keep my current low-risk job or aim higher and start the business I’ve always wanted.
There’s a gene that underlies this behavior in fruit flies commonly referred to as the “foraging gene.” It has two specific variants: One is thought of as a “rover” variant, which predicts wider and more comprehensive search paths during exploration. The other can be thought of as the “sitter” variant, which predicts a more conservative exploration style. The rover variant of the gene predicts more adventurous exploration by fruit flies and ultimately a heightened ability to find food sources within uncertain environments.
These differences in behavior seem to relate to risk aversion. A fly willing to explore widely and adventurously is more likely to find new food sources, but it also leaves itself open to new dangers like crossing a predator’s…