The oldest unevolved organism
20 Apr 2015 by qmwwwtqmqt.d qmwwwtqmqt.d
Scientists have discovered a deep-sea microorganism that shows no evidence of evolution in the last 2 billion years.
A research team at the University of California – Los Angeles (UCLA) found 2.3 billion year old deep-sea bacteria preserved in rocks that look almost identical to modern bacteria found in Chile.
“It seems astounding that life has not evolved for more than 2 billion years – nearly half the history of the Earth. Given that evolution is a fact, this lack of evolution needs to be explained,” said leader of the research Professor William Schopf at UCLA.
The research, published in Proceedings of the National Academy of Sciences, studied deep-sea sulphur bacteria fossils from Western Australia's coastal waters by using Raman spectroscopy to analyse the chemistry composition of the rock. They also used confocal laser scanning microscopy to render fossil organisms in 3D.
The bacteria fossils were dated back to the mid-Precambrian - between 2.4 billion and 2.2 billion years ago - when a substantial rise in Earth's oxygen levels known as the Great Oxidation Event is believed to have occurred.
The team then compared the fossilised organisms with modern sulphur bacteria found in mud of the coast of Chile and discovered that the environment has remained unchanged. They found that the ecosystems are consistent with the Darwinian evolution hypothesis – if there is no change in the physical-biological environment of a well-adapted ecosystem, its biotic components should similarly remain unchanged.
“The rule of biology is not to evolve unless the physical or biological environment changes, which is consistent with Darwin. These microorganisms are well-adapted to their simple, very stable physical and biological environment. If they were in an environment that did not change but they nevertheless evolved, that would have shown that our understanding of Darwinian evolution was seriously flawed,” said Professor Schopf.
