They can survive in harsher environments using less energy. Wasn't actually thinking about a rad-hard organism. Maybe throw in some flatworm, someone has to have a robust error-correcting code system built into their genetics.
Granted we would have to figure out a different neuro chemistry or physiology for having human level cognition on a much smaller energy budget.
Granted we would have to figure out a different neuro chemistry or physiology for having human level cognition on a much smaller energy budget.