This is fascinating:
Link: https://www.nytimes.com/2023/06/13/science/fruit-flies-death-aging.html
In brief, fruit flies that have witnessed or been in the presence of other dead fruit flies will age faster than fruit flies that have not. And - for reasons yet unknown, fruit flies that have been exposed to death are thereafter avoided or shunned by those of their brethren that have not witnessed death.
If the simple psychology of a fruit fly can have that kind of reaction to death or trauma, what then of people?
And, while on the surface unrelated it reminds me how once Hollywood established the convention that people fall down dead when they've been shot, and people have been doing that ever since (when in fact chances are you've got a fair bit of life in you yet...).