It has always been accepted that lower doses of radiation cause lower damage. But no-one considered that our bodies might give less priority to the lesser damage:

"However, the researchers noted that the damage from low radiation levels lingered days to weeks longer than damage induced by more powerful levels. They observed that when the cell cultures multiplied, the numbers of double-strand breaks decreased.

This might be because instead of repairing the damage, the body simply gets rid of these damaged cells with induced cell death, the duo suggested. In high doses of radiation, more cells b damaged - too many to kill off - so the body repairs the damage instead."

So, how might our bodies react to massive doses of cosmic radiation. Scientists who merely extrapolate data from standard or large doses might be ignoring the possibility that our bodies react intelligently.

radiation > mutation > evolution