Re: Earth without oxygen

Brian Davis skreiv:

> The fact that everything that splits water as a proton source uses the
> same enzyme, "Z", to do so? If I have to bet on evolution happening
> only once, or happening exactly the same way twice in succession, I'll
> go with a single origin.

There's also the possibility of it having happened multiple times, but 
the other ones having died off.


	Eivind Kjorstad