[Drammach]

Well, the Earth does have two known asymmetries - its direction of rotation and the polarity of its magnetic field. The former raises an immediate problem - best illustrated by the old "water down the toilet" joke - any asymmetry in the northern hemisphere would surely require the opposite asymmetry in the southern.

Unfortunately, that's an Urban Legend.. it's the same direction for north and south of the hemisphere..

As for the magnetic field, I'm just not sure what you're talking about..
Deformity caused by Solar Wind?

[John Locke]

Unfortunately, that's an Urban Legend.. it's the same direction for north and south of the hemisphere..

Yes, I know - that's why I called it a joke!

But on the larger scale - the prevailing winds, for instance - the two hemispheres are antisymmetric. How this would affect living things is, of course, another problem.

On the magnetic field - we know that many living things are sensitive to the Earth's magnetic field - many species of migratory bird, for instance. And any small organism containing a metallic ion can also, in principle, detect the field. Put together the magnetic field (N/S), the gravitational field (up/down) and the Coriolis force (E/W) and we have a classic "right hand / left hand" rule situation - a true asymmetry. This could perhaps preference left-handed over right-handed molecules, though at present we have no idea how.

As I said, a big problem.