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To be clear, you are not suggesting that Cyanobacteria originated from extraterrestrial origins. But when it evolved on earth, it then wiped out all non-Cyanoba
by Balero 4y ago
To be clear, you are not suggesting that Cyanobacteria originated from extraterrestrial origins. But when it evolved on earth, it then wiped out all non-Cyanobacteria?
- SideburnsOfDoom 4y ago> But when it evolved on earth, it then wiped out all non-Cyanobacteria? Most, not all were either wiped out or survive only in small anaerobic niches. It was a mass extinction. https://en.wikipedia.org/wiki/Great_Oxidation_Event https://en.wikipedia.org/wiki/Great_Oxidation_Event
- denton-scratch 4y agoNo, I'm not suggesting that! When cyanobacteria evolved, they filled the world with molecular oxygen, which was toxic to most of the other organisms on Earth. The cyanobacteria could cope with the O2; so effectively, they terraformed the Earth into a place they could live, at the expense of the organisms that were doing very nicely, thank you, until the cyanobacteria turned up. I don't believe that life travels between stars. It can't happen by accident; it has to be done by a sophisticated civilisation. The only evidence I have of such a civilisation is ours, and it's only been able to launch space rockets for a few decades. And our civilisation was living in caves just a few millennia ago. I have no reason to believe we are more than a flash in the pan. I feel sure that in a few more millennia, if we're still around, we won't be interested in interstellar probes we fired-off in antiquity.
- ncmncm 4y agoNot true: any old asteroid strike launches millions of microbe-bearing rocks into interstellar trajectories. Any that do reach another planet might take millions of years to get there, and be vanishingly unlikely to pick one that microbes can survive on. But it is wholly possible, and wholly possible that we got infected in exactly that way.