Back on topic, I think that Elezen have a longer lifespan because it's expected, as in most games, that elves live longer. I tend to run with the personal headcanon (as we don't have a lot to back it up), that Elezen and Lalafell are the two longest lived races if only because of the way they live. I expect an Elezen adventurer is as prepared for death as their Hyurian counterparts. So I would more say that lifespan is directly proportionate to the occupation of the individual, and the lifestyle they live as a character.
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