Thanks Red Badger.
Posted on 04/08/2021 12:46:47 PM PDT by Red Badger
It's like something out of science fiction. Research led by Bigelow Laboratory for Ocean Sciences has revealed that a group of microbes, which feed off chemical reactions triggered by radioactivity, have been at an evolutionary standstill for millions of years. The discovery could have significant implications for biotechnology applications and scientific understanding of microbial evolution.
"This discovery shows that we must be careful when making assumptions about the speed of evolution and how we interpret the tree of life," said Eric Becraft, the lead author on the paper. "It is possible that some organisms go into an evolutionary full-sprint, while others slow to a crawl, challenging the establishment of reliable molecular timelines."
Becraft, now an assistant professor of biology at the University of Northern Alabama, completed the research as part of his postdoctoral work at Bigelow Laboratory and recently published it in the Nature publishing group's ISME Journal.
The microbe, Candidatus Desulforudis audaxviator, was first discovered in 2008 by a team of scientists, led by Tullis Onstott, a co-author on the new study. Found in a South African gold mine almost two miles beneath the Earth's surface, the microbes acquire the energy they need from chemical reactions caused by the natural radioactive decay in minerals. They inhabit water-filled cavities inside rocks in a completely independent ecosystem, free from reliance on sunlight or any other organisms.
Because of their unique biology and isolation, the authors of the new study wanted to understand how the microbes evolved. They searched other environmental samples from deep underground and discovered Candidatus Desulforudis audaxviator in Siberia and California, as well as in several additional mines in South Africa. Since each environment was chemically different, these discoveries gave the researchers a unique opportunity to look for differences that have emerged between the populations over their millions of years of evolution.
"We wanted to use that information to understand how they evolved and what kind of environmental conditions lead to what kind of genetic adaptations," said Bigelow Laboratory Senior Research Scientist Ramunas Stepanauskas, the corresponding author on the paper and Becraft's postdoctoral advisor. "We thought of the microbes as though they were inhabitants of isolated islands, like the finches that Darwin studied in the Galapagos."
Using advanced tools that allow scientists to read the genetic blueprints of individual cells, the researchers examined the genomes of 126 microbes obtained from three continents. Surprisingly, they all turned out to be almost identical.
"It was shocking," Stepanauskas said. "They had the same makeup, and so we started scratching our heads."
Scientists found no evidence that the microbes can travel long distances, survive on the surface, or live long in the presence of oxygen. So, once researchers determined that there was no possibility the samples were cross-contaminated during research, plausible explanations dwindled.
"The best explanation we have at the moment is that these microbes did not change much since their physical locations separated during the breakup of supercontinent Pangaea, about 175 million years ago," Stepanauskas said. "They appear to be living fossils from those days. That sounds quite crazy and goes against the contemporary understanding of microbial evolution."
What this means for the pace of microbial evolution, which often happens at a much more accelerated rate, is surprising. Many well-studied bacteria, such as E. coli, have been found to evolve in only a few years in response to environmental changes, such as exposure to antibiotics.
Stepanauskas and his colleagues hypothesize the standstill evolution they discovered is due to the microbe's powerful protections against mutation, which have essentially locked their genetic code. If the researchers are correct, this would be a rare feature with potentially valuable benefits.
Microbial enzymes that create copies of DNA molecules, called DNA polymerases, are widely used in biotechnology. Enzymes with high fidelity, or the ability to recreate themselves with little differences between the copy and the original, are especially valuable.
"There's a high demand for DNA polymerases that don't make many mistakes," Stepanauskas said. "Such enzymes may be useful for DNA sequencing, diagnostic tests, and gene therapy."
Beyond potential applications, the results of this study could have far-reaching implications and change the way scientists think about microbial genetics and the pace of their evolution.
"These findings are a powerful reminder that the various microbial branches we observe on the tree of life may differ vastly in the time since their last common ancestor," Becraft said. "Understanding this is critical to understanding the history of life on Earth."
Explore further
Study reveals two major microbial groups can't breathe More information: Eric D. Becraft et al, Evolutionary stasis of a deep subsurface microbial lineage, The ISME Journal (2021). DOI: 10.1038/s41396-021-00965-3 Journal information: ISME Journal
Provided by Bigelow Laboratory for Ocean Sciences
>>What is crevo?<<
The CREVO wars were VERY lengthy and acrimonious arguments between people on FR who understand science and evolution and FR creationists, many Young Earth Creationists who believe the Earth (and by extension the Universe) is 6,000 years old (ascertained by computations from the Begats in the Bible). Thus CREationist/EVOlution wars.
JR finally took matters into hands and blanket banned all Evolutionists, who started another board dedicated to scientists who are also conservatives. I cannot name it out loud and continue to exist here.
I am one of the very few, if not the only, survivor. I was banned for 2 years but was allowed back in since I decided that the that discussion was less important than what was politically happening at the time - TEA party and then candidate obozo. It was better we put such squabbles behind us to face the real foe.
So now I will come into a thread like this, state true science as I have done here, then leave and let the people who cite “references” like Institute for Creation Research and other pseudo-science sources crow and echo each other until the thread dies a swift death.
My “job” is to let the world know that there are those of use at FR who do indeed know science. And to mock and correct demonstrable ignorance such as the definition of a Scientific Theory.
But I am always careful.
>>“They had the same makeup, and so we started scratching our heads.” Like a bunch of monkeys that they are. Pure conjecture, nothing more.<<
Not a big fan of scientific curiosity I see. Other than EVERY SINGLE SCIENTIFIC DISCOVERY EVER, nothing ever resulted from “scratching our heads” and wondering.
Telsa did the same. Babbage did the same. Moore did the same. Heck, Ook Grunt who tied a rock to a stick to make the first hammer did the same.
Every night you should get on your knees in your air conditioned above ground home after you get off your computer having eaten a meal obtained through a modern delivery system and thank GOD for head scratchers.
Like panty-sniffer Joe?
No, they believe the rocks it was discovered in are that age. None of us were actually here to witness those rocks being formed, and they do not have a datestamp on them.
This article highlights one of the pitfalls of basing science on the assumption of uniformitarianism, and geological dating is subject to the same kinds of pitfalls.
OK
Creationists vs evolutionists = CREVO
I just did not understand the acronym.
I am a member of SOPWAOS.
(society of people who avoid obscure acronyms)
This really isn’t surprising. If it works, why change it? And, the energy available is small and getting smaller over geologic time.
It is interesting to consider that change hardening human DNA would probably radically lengthen healty lifespan potential (like naked mole rats) assuming good eating/excersize habits and make people somwhat radiation resistant.
It seems like they could sequence the genomes to see how “different” the genomes are. They may have to take in to consideration epigenetic control of dna expression also.
When I was in school I was taught evolution ALWAYS occurs...but there are many extant organisms which show little or no change...cockroaches...coelocanth...tuatara...wollemi pine...and now these bacteria...so the oxymoron “living fossils” was coined.
Would be interesting to see the sizes of the genome and the different endonucleases and energy transfer systems as well as the dna correction enzymes and if there is lateral gene transfer as seen in other bacteria. Maybe these orgs can live in other environments and can become motile in different environments. Lots to learn here.
Living fossil...Joe Biden?😀
OIC :) I think in the old days we were just PAA: People Against Acronyms. Simpler times.
.
Learn to read.
I read what you said. My reaction is on point. And accurate.
Beat me to it, so I’ll use the old Bob Hope reply, “Oh you mean Democrats”.
Thanks Red Badger.
One theory, of many, about why evolutionary changes occur in organisms is that COSMIC RAYS, High speed, high energy particles from the depths of outer space, hit a strand of DNA, knocking out a gene or a piece of one, thus initiating and new genetic sequence in the organism. If it isn’t fatal it gets replicated and passed on to the progeny. If it is ‘helpful’ it gets multiplied throughout the species.
These bacteria are two mile down inside solid rock so the would be shielded from practically ALL Cosmic Rays..................
When a critter is perfectly adapted to its environment, what need does it have to adapt and evolve?
It’s not like it’s in an arms race with immune systems in its hosts, nor with competing critters...
How long ago did Pangea break up? Did the continents do all that moving apart and re colliding since in your and Ussher's 6024 years, 5 months, 17 days and 21 hours?
Some do. There are rocks in the south tip of Iceland we can date to the day and hour they solidified...
More to the point if you know the chemical composition of a crystal, and you know exactly what percentages of elements form that crystal, and some elements have a known rate of radioactive decay, and you know how much of those elements are missing from the crystal, you can estimate how long it took for that percentage of those atoms to go missing.
AND you can cross check your answer by measuring the excess of the elements they decay into that aren't part of the original crystalline structure that are trapped within the crystal.
tiamat ("Just a Bronze-Age Gal, Trapped in a Techno-World!")
I miss her.
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