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Author Topic:   Cyanobacteria weren't first, but last?
blitz77
Inactive Member


Message 1 of 7 (21564)
11-05-2002 2:16 AM


An article on Eurekalert has an article saying that cyanobacteria, the supposed earliest life on earth which produced oxygen, saying that they came ~1 billion years after than assumed. In Carrine Blank's model, sulfur-loving bacteria came ~2.4 billion years ago and the cyanobacteria about 100 million years about that. If this theory is correct, how do banded iron formations, etc fit in? Blank used genetic family trees to support this. Using the genetic tree, Blank was able to show that cyanobacteria would branch off last of the primitive bacteria.
Eurekalert

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 Message 2 by Quetzal, posted 11-05-2002 6:08 AM blitz77 has replied

  
blitz77
Inactive Member


Message 3 of 7 (21754)
11-07-2002 1:03 AM
Reply to: Message 2 by Quetzal
11-05-2002 6:08 AM


Maybe this isn't about evolution but abiogenesis, but since it is dealing with the reducing/oxidizing early atmosphere it can't really be classified in abiogensis/origin of life as it is talking about what organisms could have converted the supposed early reducing atmosphere into an oxidizing atmosphere. This may be considered as further evidence against an early reducing atmosphere--because otherwise you would need some other organism to produce oxygen, and no other candidate has been put forward. Until then, this is further evidence against an early reducing atmosphere.
[This message has been edited by blitz77, 11-07-2002]

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 Message 4 by John, posted 11-07-2002 1:30 AM blitz77 has replied

  
blitz77
Inactive Member


Message 5 of 7 (21757)
11-07-2002 1:48 AM
Reply to: Message 4 by John
11-07-2002 1:30 AM


quote:
Note that per the article cited, cyanobacteria are not the EARLIEST bacteria, but came along after the sulfer loving bacteria. It does not say that NO BACTERIA came before the cyanobacteria.
Of course, according to the article cyanobacteria aren't the first bacteria. But my point still stands-or are you suggesting these sulfur-loving bacteria produced the first oxygen in the reducing atmosphere?
[This message has been edited by blitz77, 11-07-2002]

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