Seeing dead flies causes other flies to die faster; but why?

Research shows that when fruit flies of the species Drosophila melanogaster are exposed to the carcasses of their dead friends, their lifespan is significantly reduced. Flies become withdrawn, lose body fat, and age so quickly that they die sooner than fruit flies that don’t see the corpses of other dead flies.

Scientists now have a better idea of ​​why this is the case. written by ScienceAlertWhen fruit flies see their dead companions, two types of serotonin neurotransmitter receptor neurons are activated in their brains, and this increased activity accelerates the flies’ aging process. The University of Michigan researchers write in their paper: “Understanding the neural circuits through which the perception of death affects these characteristics may provide insights into understanding the consequences of this and perhaps other sensory experiences even in humans. provide how specific neural states affect behavior and physiology.”

Sensory processes can influence aging, but we don’t know much about how it happens. Previous research by the same group of researchers has shown that the perception of dead flies has the same noticeable effect on fruit flies and they die earlier, but the reasons for this were unknown.

Similar effects have been observed in other animals: necrophoresis, or scavenging of dead conspecifics, in social insects; vocalization and corpse inspection in elephants or increased levels of regulatory hormones called glucocorticoids in non-human primates.

In fruit flies, the changes appeared to involve serotonin, an important neurotransmitter that transmits signals between nerve cells, and one of the serotonin receptors called 5-HT2A. The researchers began their work from this point and investigated which neurons expressing the serotonin 2 receptor might play a role in the physical effects of what the researchers call the “perception of death.”