“To deal with their miserable lives” naked mole rats evolved to feel no pain:
And yet in this harsh environment, under extremely crowded conditions, the naked mole rat has evolved to be virtually indestructible: these small mammals almost never get cancer, live to be over 30 (much longer than other rat species), and they are insensitive to acid burns. Now a new study in Cell Reports reveals one secret behind these rats’ abilities. Evolutionary tweaks to the amino acids in their pain receptors make naked mole rats extremely insensitive to pain after they are born.
I think it’s surprising and fascinating that immunity to pain isn’t a more common adaptation in biology. Clearly pain has potent survival benefits — the ultimate double-edged sword.