New Study Reveals How Artificial Lights Confuse Flying Insects’ Navigation Systems
In a groundbreaking study published in the journal Nature Communications, researchers have discovered that artificial lights at night may be disrupting the navigational systems of flying insects. Contrary to popular belief, these insects are not actually attracted to light but rather become disoriented and confused by it.
For years, scientists and poets alike have assumed that flying insects were irresistibly drawn to bright lights, like moths to a flame. However, this new research challenges that notion and suggests that insects use light as a cue to determine their orientation in the world.
“Insects have a navigational problem,” explains Tyson Hedrick, a biologist at the University of North Carolina. “They’re accustomed to using light as a cue to know which way is up.”
The study, conducted by a team of entomologists from Imperial College London, involved attaching tiny sensors to moths and dragonflies in a laboratory setting. This allowed the researchers to capture “motion-capture” video footage of the insects’ flight patterns, similar to how filmmakers track actors’ movements. Additionally, high-resolution cameras were used to film insects in Costa Rica swirling around artificial lights.
The findings revealed that instead of flying directly towards a light source, insects actually tilt their backs towards the light. This behavior would make sense if the strongest light source was in the sky. However, in the presence of artificial lights, it leads to confusion and disorientation rather than attraction.
Dragonflies, in particular, were observed circling endlessly around light sources, positioning themselves with their backs facing the beams. Some insects even flipped upside down and crash-landed when exposed to lights that shone straight upward, resembling searchlights. Interestingly, the researchers found that bright lights shining straight downward had the least disruptive effect on insect flight.
“For millions of years, insects oriented themselves by sensing that the sky is light, the ground is dark,” says Avalon Owens, a Harvard entomologist who was not involved in the study. However, the invention of artificial lights by humans has disrupted this natural balance and caused confusion among flying insects.
The implications of this research are significant, as it sheds light on the potential consequences of artificial lighting on insect populations. Insects play a crucial role in ecosystems as pollinators and as a food source for other animals. Disrupting their navigational systems could have far-reaching effects on the natural world.
While further research is needed to fully understand the extent of this phenomenon and its ecological impact, this study serves as a reminder that our actions can have unintended consequences on the delicate balance of nature. As we continue to illuminate our cities and landscapes with artificial lights, it is important to consider the potential effects on the creatures that share our planet.