Think along the lines of this as well.
These events happen everyday, for all kinds of purposes we all experience and
take for granted.
This runs alongside my idea of the walrus forming bone from callus due to adaptation to its colder environment.
This guy retains water to transport back and regurgetates it to help his village get clean water.

Stuck in space? No sun, too much sun?
Rescued from a planet after years of exposure to heavier gravity, protein rich environment therefore strengthening
the exposed body to maximum ?superhuman potential?! ...
Stuck underground?
Harsh timultuous environment?
Challenging environment?
Tarzan and the enlarged hands grown to keep up with his primate tree climbing pack?!


What would you encounter under "given" experiences you imagine up.
Its easier to imagine then u think.

This video is an example of our own unlocked or taken for granted hidden potential and perk!!

Think something up good, and let your environmts and characters reflect the given situations.