April 09, 2009 — Edmonton-A University of Alberta researcher is lead author on a paper
that reaches back billions of years to establish a new link between
nickel, methane gas and the evolution of complex life forms on Earth.
Kurt
Konhauser, professor of geomicrobiology at the U of A, and an
international team of researchers came together for the paper that will
be published in Nature on April 9.
caused the decline of methane producing bacteria 2.7 billion years ago
and the subsequent rise of oxygen levels. This new paper shows that as
the planet’s mantle cooled there was a sharp decrease in nickel-rich
volcanism.
"Nickel was the nutrient that methogen bacteria used
to produce methane gas," said Konhauser. "The methogens starved, and as
methane gas levels fell, oxygen levels rose in the oceans and in the
atmosphere."
Approximately 2.4 billion years the planet became oxygenated to a level that allowed the evolution of complex life forms.
Konhauser
says that this paper is the first to link to changes in Earth’s
volcanism to the microbial populations that determined the timing for
the rise of atmospheric oxygen.
Source : University of Alberta