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TOLAY IN HISTORY
November 2nd
On this day in 1977, a report by Carl R. Woese was published that identified
methanogens, an ancient life form that has existed on Earth for 3.5 billion
years. Woese studied the unicellular organisms and discovered they lived in
oxygen-deficient environments and survived by reducing carbon dioxide to
methane. In the report, Woese stated these organisms were so different from
other living things that we should change the classification system and place
methanogens in a new and separate domain, Archaea.
Phylogenetic Tree of Life
Questions:
1. If these were one of the first organisms to
live on Earth, what kind of conclusions can
we make about conditions on Earth
billions of years ago?
2. Do you think it's possible that we will
discover other unique and different
organisms that require modification of the
current classification system?
Bacteria
Archas
Eucarya