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AFAIK, the ability to tolerate oxygen is an advanced property of terrestrial life — the simplest, oldest life forms were totally unable to survive in the presen

AFAIK, the ability to tolerate oxygen is an advanced property of terrestrial life — the simplest, oldest life forms were totally unable to survive in the presence of oxygen.

gizmo686 8y ago
The Great Oxygenation Event [0]. Arguably the planet's first mass extinction. To say that nothing we have done to the planet is as bad for the environment as the Great Oxygenation Event would be to pat ourselves on the back for not literally poisoning the atmosphere. [0] https://en.wikipedia.org/wiki/Great_Oxygenation_Event https://en.wikipedia.org/wiki/Great_Oxygenation_Event
- deleted 8y ago
  [deleted]
- cbkeller 8y ago
  Geologist here. Yeah, there are a few places you can find microbial survivors of the GOE: https://en.wikipedia.org/wiki/Green_sulfur_bacteria https://en.wikipedia.org/wiki/Green_sulfur_bacteria https://en.wikipedia.org/wiki/Purple_sulfur_bacteria https://en.wikipedia.org/wiki/Purple_sulfur_bacteria Obligate anaerobic photoautotrophs: they photosynthesize, and need light to survive, but don't produce (and are killed by) O2. Unfortunately for them, post-GOE, there aren't many habitats that are anoxic but still have much light! There's at least one clade of "green sulfur bacteria" that apparently lives off the basically-invisible glow from a black smoker at a mid-ocean ridge: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1166624/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1166624/ fascinating stuff!
  - Balgair 8y ago
    PBS Eons is a great youtube channel on Earth's biological history. It's very well done stuff. Their 'Purple Earth' video is a good layman's intro to some of the per-oxygenation earth: https://www.youtube.com/watch?v=IIA-k_bBcL0 https://www.youtube.com/watch?v=IIA-k_bBcL0 The early biological history of Earth has a few 'Colored Earth' phases: Red-Purple-Green-White-Blue(hypothetically).
gnulinux 8y ago
Not only that but it's possible that life surviving in the presence of oxygen might be a rare occurrence as far as life goes. One of the reasons terrestrial life is mostly aerobic might be because we're all the very few survivers of the Great Oxygenation Event which killed almost all the life on earth. If something like that didn't happen in the history of evolution in other planets, they might not have evolved to ingest oxygen.

AFAIK, the ability to tolerate oxygen is an advanced property of terrestrial life — the simplest, oldest life forms were totally unable to survive in the presence of oxygen.

gizmo686 8y ago

The Great Oxygenation Event [0]. Arguably the planet's first mass extinction. To say that nothing we have done to the planet is as bad for the environment as the Great Oxygenation Event would be to pat ourselves on the back for not literally poisoning the atmosphere. [0] https://en.wikipedia.org/wiki/Great_Oxygenation_Event https://en.wikipedia.org/wiki/Great_Oxygenation_Event

deleted 8y ago
[deleted]
cbkeller 8y ago
Geologist here. Yeah, there are a few places you can find microbial survivors of the GOE: https://en.wikipedia.org/wiki/Green_sulfur_bacteria https://en.wikipedia.org/wiki/Green_sulfur_bacteria https://en.wikipedia.org/wiki/Purple_sulfur_bacteria https://en.wikipedia.org/wiki/Purple_sulfur_bacteria Obligate anaerobic photoautotrophs: they photosynthesize, and need light to survive, but don't produce (and are killed by) O2. Unfortunately for them, post-GOE, there aren't many habitats that are anoxic but still have much light! There's at least one clade of "green sulfur bacteria" that apparently lives off the basically-invisible glow from a black smoker at a mid-ocean ridge: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1166624/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1166624/ fascinating stuff!
- Balgair 8y ago
  PBS Eons is a great youtube channel on Earth's biological history. It's very well done stuff. Their 'Purple Earth' video is a good layman's intro to some of the per-oxygenation earth: https://www.youtube.com/watch?v=IIA-k_bBcL0 https://www.youtube.com/watch?v=IIA-k_bBcL0 The early biological history of Earth has a few 'Colored Earth' phases: Red-Purple-Green-White-Blue(hypothetically).

gnulinux 8y ago

Not only that but it's possible that life surviving in the presence of oxygen might be a rare occurrence as far as life goes. One of the reasons terrestrial life is mostly aerobic might be because we're all the very few survivers of the Great Oxygenation Event which killed almost all the life on earth. If something like that didn't happen in the history of evolution in other planets, they might not have evolved to ingest oxygen.