Is man an evolutionary freak?

Bruno Perella said:

When the earth's magnetic poles 'flip over' as in the
past, exposing the surface of the planet to the
bombardment of high energy solar cosmic radiation, could
this not result in the genetic mutation of organisms on
the surface? Are we the end result of a 'beneficial'
mutation?

Complete loss of the Earth's magnetic field would produce a
substantial increase in cosmic ray radiation at the Earth's
surface -- roughly a factor of two. Cosmic rays are only a
small fraction of the total background radiation, however,
so the net increase in radiation would only be about 10%,
which is much smaller than the variation in background rate
in different locations now. And since radiation contributes
only a small fraction of the mutation rate, the total effect
would be very small.

--
Steve Schaffner [email hidden] Immediate assurance is an
excellent sign of probable lack of insight into the topic.
Josiah Royce