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The irreversible global catastrophe is imperialist militaries massacring people with little risk to themselves. 
The irreversible global catastrophe is assembly line robots at the Toyota plant becoming sentient and going on a freaking epic terminator style mass shooting and enslave everyone except me 
Matabele ants have been observed picking up and carrying nest mates who emit a specific pheromone that signals to others that they have been wounded. Back at the nest, others lick the injured ant's wounds and it decreases overall mortality by like 30 percent iirc.
(My favorite element of this behavior is that some ants have also been observed "faking" their wound signal to get carried back, though it's hard to say whether this is intentional. Other injured ants will even fight off their would-be rescuers if they are so wounded that they will not recover.)
Lol I know right, what a sharp little nugget of drama hidden away in such a small society