TY - JOUR
T1 - Sulfur-cycling fossil bacteria from the 1.8-Ga Duck Creek Formation provide promising evidence of evolution's null hypothesis
AU - Schopf, J. William
AU - Kudryavtsev, Anatoliy B.
AU - Walter, Malcolm R.
AU - Van Kranendonk, Martin J.
AU - Williford, Kenneth H.
AU - Kozdon, Reinhard
AU - Valley, John W.
AU - Gallardo, Victor A.
AU - Espinoza, Carola
AU - Flannery, David T.
N1 - Publisher Copyright:
© 2015 PNAS.
PY - 2015/2/17
Y1 - 2015/2/17
N2 - The recent discovery of a deep-water sulfur-cycling microbial biota in the ~2.3-Ga Western Australian Turee Creek Group opened a new window to life's early history. We now report a second such subseafloor-inhabiting community from the Western Australian ~1.8-Ga Duck Creek Formation. Permineralized in cherts formed during and soon after the 2.4-to 2.2-Ga "Great Oxidation Event," these two biotas may evidence an opportunistic response to the mid-Precambrian increase of environmental oxygen that resulted in increased production of metabolically useable sulfate and nitrate. The marked similarity of microbial morphology, habitat, and organization of these fossil communities to their modern counterparts documents exceptionally slow (hypobradytelic) change that, if paralleled by their molecular biology, would evidence extreme evolutionary stasis.
AB - The recent discovery of a deep-water sulfur-cycling microbial biota in the ~2.3-Ga Western Australian Turee Creek Group opened a new window to life's early history. We now report a second such subseafloor-inhabiting community from the Western Australian ~1.8-Ga Duck Creek Formation. Permineralized in cherts formed during and soon after the 2.4-to 2.2-Ga "Great Oxidation Event," these two biotas may evidence an opportunistic response to the mid-Precambrian increase of environmental oxygen that resulted in increased production of metabolically useable sulfate and nitrate. The marked similarity of microbial morphology, habitat, and organization of these fossil communities to their modern counterparts documents exceptionally slow (hypobradytelic) change that, if paralleled by their molecular biology, would evidence extreme evolutionary stasis.
KW - Great Oxidation Event
KW - Microbial evolution
KW - Null hypothesis
KW - Precambrian microorganisms
KW - Sulfur bacteria
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U2 - 10.1073/pnas.1419241112
DO - 10.1073/pnas.1419241112
M3 - Article
C2 - 25646436
AN - SCOPUS:84923166586
VL - 112
SP - 2087
EP - 2092
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 7
ER -