Along comes a new paper by William Schopf whose earlier claim to fame was the discovery of 3.5 billion year old fossils. A claim that has been discredited. The "fossils" weren't fossils [Did Life Arise 3.5 Billion Years Ago?]. The latest study was funded by the NASA Astrobiology Institute.
I can't read the paper right now because I don't have access but here's the summary from PNAS.
An ancient deep-sea mud-inhabiting 1,800-million-year-old sulfur-cycling microbial community from Western Australia is essentially identical both to a fossil community 500 million years older and to modern microbial biotas discovered off the coast of South America in 2007. The fossils are interpreted to document the impact of the mid-Precambrian increase of atmospheric oxygen, a world-changing event that altered the history of life. Although the apparent 2-billion-year-long stasis of such sulfur-cycling ecosystems is consistent with the null hypothesis required of Darwinian evolution—if there is no change in the physical-biological environment of a well-adapted ecosystem, its biotic components should similarly remain unchanged—additional evidence will be needed to establish this aspect of evolutionary theory.Ugh! While it might be true that perfectly adapted organisms aren't going to show any new fixations of beneficial alleles in an unchanging environment, that does not mean that there won't be neutral, or even deleterious, changes in its "biotic components."
If we look at the UCLA website, we get a more complete picture of Schopf's views [Scientists discover organism that hasn’t evolved in more than 2 billion years].
The scientists examined sulfur bacteria, microorganisms that are too small to see with the unaided eye, that are 1.8 billion years old and were preserved in rocks from Western Australia’s coastal waters. Using cutting-edge technology, they found that the bacteria look the same as bacteria of the same region from 2.3 billion years ago — and that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria found in mud off of the coast of Chile.Repeat after me, "Evolution does not equal natural selection. Evolution does not equal natural selection. Evolution does not equal natural selection. Evolution does not equal natural selection. Evolution does not equal natural selection. .."
“It seems astounding that life has not evolved for more than 2 billion years — nearly half the history of the Earth,” said J. William Schopf, a UCLA professor of earth, planetary and space sciences in the UCLA College who was the study’s lead author. “Given that evolution is a fact, this lack of evolution needs to be explained.”
Charles Darwin’s writings on evolution focused much more on species that had changed over time than on those that hadn’t. So how do scientists explain a species living for so long without evolving?
“The rule of biology is not to evolve unless the physical or biological environment changes, which is consistent with Darwin,” said Schopf, who also is director of UCLA’s Center for the Study of Evolution and the Origin of Life. The environment in which these microorganisms live has remained essentially unchanged for 3 billion years, he said.
“These microorganisms are well-adapted to their simple, very stable physical and biological environment,” he said. “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.”
Schopf said the findings therefore provide further scientific proof for Darwin’s work. “It fits perfectly with his ideas,” he said.
Here's a question for all Sandwalk readers. How many of you think that the sequences of all modern sulfur bacteria (several thousand species) show almost no evidence of evolution such that phylogenetic trees made with those sequences all have the sulfur bacteria down at the very base of the tree?
PNAS ought to be ashamed of itself. The editor was Thomas N. Taylor of the Department of Ecology & Evolutionary Biology at the University of Kansas who describes himself like this ....
I am a member of the National Academy of Sciences, currently serving a six-year term on the presidentially appointed National Science Board, where I am involved with a variety of science policy issues ranging from K–12 education to support for major infrastructure investments designed to make the U.S. more competitive in research and public science literacy.