August 26, 2026, 10:51 am | Read time: 3 minutes
Fruit flies are not known for their longevity. However, the sight of dead peers can apparently shorten their lives even further. Researchers in the U.S. discovered in 2019 that fruit flies exposed to dead members of their own species age faster, build up fewer fat reserves, and struggle more with hunger. In a new study, scientists have explored why merely seeing death has such effects. The findings provide surprising insights into the biological mechanisms behind stress and aging.
The Fruit Fly Experiment
The previous findings by study authors Tuhin S. Chakraborty, Christi M. Gendron, and their colleagues suggested that specific serotonin receptors, called 5-HT2A, might be responsible for accelerating the aging process in flies. These receptors are found in the central nervous system, among other places, and influence various biochemical processes.
For the study published in the journal “PLOS Biology,” the researchers made the activity of certain nerve cells visible using fluorescent markers. Chakraborty, Gendron, and their colleagues then placed the flies in a room with several dead peers. The dead flies were placed in “normal food,” according to the study. Overall, the living insects were exposed to the dead ones for several days.
Initially, the research team examined what happens in the brains of fruit flies when they perceive dead peers. Subsequently, the scientists deliberately activated certain nerve cells to artificially trigger the same reaction. This allowed them to identify two types of nerve cells that play a crucial role in processing such impressions.
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What the Fruit Fly Study Has to Do With Humans
The results show that the sight of dead peers triggers certain processes in the brain associated with faster aging. An interesting, albeit not necessarily useful, piece of information—at least when it comes to applying it to the human brain. After all, a fruit fly’s brain is vastly different from a human brain.
According to the study authors, the findings help better understand how the perception of death affects the body and which biological processes are involved. “Our results could provide insights for treating individuals who are regularly confronted with death, such as soldiers or first responders,” the scientists write. Even though the results cannot be directly applied to humans, they offer intriguing avenues for further research.
As for fruit flies in your own home, there’s probably no need to leave dead peers lying around. Other measures are likely much more effective against a fruit fly infestation.