03-02-2013, 05:02 PM
(This post was last modified: 03-02-2013, 05:04 PM by stevebowers..)
One difference that has come up in discussions elsewhere on the 'Net is that chlorine photosynthesis might prevent the evolution of oxygen photosynthesis, probably by chlorine and oxygen reaction to form sterilising hypochlorite compounds. If life can evolve to tolerate bleach-like compounds then maybe a chlorine/oxygen environment could form, but it would be very far outside of chemical equilibrium.
I note that methane and oxygen were both present in Earth's early atmosphere during the Proterozoic era, but they should react with each other quite rapidly. Life processes replenished both as quickly as they could react with each other. Given the right circumstances chlorine and oxygen could conceivably co-exist, but it seems likely that one or the other would predominate (probably oxygen, since it is the more common element).
I note that methane and oxygen were both present in Earth's early atmosphere during the Proterozoic era, but they should react with each other quite rapidly. Life processes replenished both as quickly as they could react with each other. Given the right circumstances chlorine and oxygen could conceivably co-exist, but it seems likely that one or the other would predominate (probably oxygen, since it is the more common element).