09-21-2015, 03:41 PM
(This post was last modified: 09-21-2015, 03:41 PM by stevebowers.)
This would be a very short history for an Earth-like planet. You are supposing that an oxygen-rich atmosphere and advanced life in an era that (on Earth) barely had single-celled organisms and a reducing atmosphere. The development of complex metazoan life might be crammed into a single gigayear, but not half of that period.
...unless you imagine a completely different mechanism for evolution. If somehow the primitive biosphere can be persuaded to follow an accelerated path somehow, allowing the rapid development of new species. Perhaps the early microbiota develop neural nets inside their microbial mats, and start to actively design new lifeforms. Active evolution, or (semi-)intelligent design of sorts. Some weird organisms might result, but they might be quickly replaced by more sensible designs.
...unless you imagine a completely different mechanism for evolution. If somehow the primitive biosphere can be persuaded to follow an accelerated path somehow, allowing the rapid development of new species. Perhaps the early microbiota develop neural nets inside their microbial mats, and start to actively design new lifeforms. Active evolution, or (semi-)intelligent design of sorts. Some weird organisms might result, but they might be quickly replaced by more sensible designs.