Cambrian Explosion: role of oxygen (Introduction)

by David Turell , Thursday, January 07, 2016, 15:09 (3025 days ago) @ dhw


> dhw: Their argument is pure speculation. The fact that pre-Cambrian organisms and some existing organisms could live on 4%, and some existing organisms can adapt to lower levels, does not mean that NEW organisms could have come into existence at that level. The authors' vague speculations, acknowledged in their tentative “maybe”, do not in any way invalidate the possibility that the Cambrian Explosion was triggered by an increase in oxygen offering opportunities for new forms of life. But it remains a hypothesis, and still doesn't solve the mystery of the mechanism that enables innovation.-Of course it is speculation, but not unreasonable as I pointed out. Oxygen was not the 'trigger'. For a trigger to work you need a whole gun and bullets, and a finger to pull it, as you point out. Of course I know who had the finger!