I fear this question may be somewhat premature as I’m suddenly skipping forward to a period in the species’ history that is comparable to our own, a far cry from my last question about the building blocks of life.
The short of it is; over countless generations the life expectancy of the species in question has shown a steady and unending rise, going from the poor expectations our own ancestors were familiar with and progressing towards lives of centuries (and after the scenario I’m about to propose a lot longer).
At some point things are going to go awry, life expectancy will peak before dropping and then very suddenly death tolls will rise and it will become apparent to all that these things are connected that something is desperately wrong.
Now a while ago in other questions I spoke about symbiotic relationships and portrayed the species as very complex and almost deliberate microbiome and my rough plan was to have something like...
“the longer they live the greater the buildup of waste chemicals from these symbiotic parasites (insert appropriate word) and that it’s not a problem until it becomes too great and subsequently it’s resulted in some sort of genetic deficiency that it now rearing its ugly head en masse”.
...that was a wild moment of imagination whilst first establishing the history.
Question: Are there existing examples of what I’m describing and is there almost a list of ‘usual suspects’ for this sort of thing? Or are we delving too far into fantasy? I don’t know enough about biology to seek analogies in medicine. I know it’s nothing like cancer, that much is sure.
It is a bit of a plot sensitive moment, a lot of key decisions are made as a result of the tragedy. It’s the greatest test they’ve faced since the end of the Stone Age.