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Antibiotic Resistance Didn’t Evolve; It Was Borrowed

first_imgExercise: On a Reference Page about antibiotic resistance, Science Daily blatantly says, “Antibiotic resistance evolves naturally via natural selection through random mutation,” and also, “Antibiotic resistance is a consequence of evolution via natural selection.” The article claims Wikipedia as its source. But now, go to the Wikipedia link cited by Science Daily: there is nothing there about natural selection! There is, however, quite a bit about horizontal gene transfer. As of this writing the Wikipedia page was last updated on June 16, 2017. Is it possible that Science Daily has old fake news on its page that has not been updated to reflect the growing realization that antibiotic resistance is no longer a good argument for evolution? A key ‘proof’ of evolution in action falls as scientists discover that pathogens don’t invent resistance genes; they share them.It was common in creation-evolution debates in the 1980s to use antibiotic resistance as proof of evolution. ‘Evolution is as common as the disease germ that is resistant to antibiotics today but wasn’t last year,’ the argument went. Who would have thought that the very organisms that produce antibiotics also produce resistance genes to fight them? And who would have thought that they can share that pre-existing genetic information with disease germs?A paper this month in Nature Communications (open access) shares findings about “Dissemination of antibiotic resistance genes from antibiotic producers to pathogens.” They show how the genomes of Actinobacteria, that live in soil, include resistance genes against the antibiotics they create. This makes sense, because they don’t want to die of their own poison. But then, they found that other bacteria from other phyla and other organisms even from different kingdoms can obtain those secrets from the Actinobacteria. This kind of “horizontal gene transfer” is not evolution, because the genetic information already existed. It’s more like passing around prefabricated exploit code between hackers or, better yet, antivirus software from service suppliers. The scientists found resistance genes in the pathogens that in some cases were 100% identical to those in Actinobacteria. But how did they get them?A press release from the Technical University of Denmark explains how the information sharing works:At first, it was difficult to imagine how pathogens can acquire genes from Actinobacteria, because they are so different and not at all related with each other. But by investigating the DNA sequence around the resistance genes, the team figured out how the resistance genes transfer occurred through a new mechanism named “carry back”, where the pathogen basically has a primitive form of “sex” with the Actinobacterium and takes up its resistance genes after it dies.This gene transfer by carry back could in principle happen where pathogens come into contact with Actinobacteria, like in an animal farm or in soil polluted with untreated hospital waste. In this way, the pathogen can become resistant and endanger human lives in the next round of infection.Since the germs without the resistance genes die off, the only ones left are those who got the genes beforehand. But they didn’t ‘evolve’ that resistance; they borrowed it (or stole it).Proteobacteria are well known to be able to transfer DNA to organisms from other phyla and even other kingdoms by conjugationFor several decades, some scientists believed that horizontal gene transfer was responsible, but they didn’t have proof. Creation debaters, similarly, tried to argue that the resistance traits already existed and were accentuated by application of antibiotics. There was no ‘smoking gun’ till now. The authors say in their concluding discussion,Proteobacteria [which include some pathogens] are well known to be able to transfer DNA to organisms from other phyla and even other kingdoms by conjugation. A recent study suggested that conjugation from proteobacteria to actinobacteria might happen frequently in soil. Thus, the ‘carry-back’ mechanism might have mediated the HGTs [horizontal gene transfers] from actinobacteria to proteobacteria in soil using conjugative plasmids as the carrier sequence. In modern times, likely caused by increased selection pressure due to the extensive use of antibiotics, mobile genetic elements including conjugative plasmids, integrons and transposons tend to be clustered together with ARGs [antibiotic resistance genes] forming mobile multidrug-resistant units. These units showed extraordinary capability of spreading among commensals, pathogens and even environmental bacteria in water and soil.Now that resistance is becoming clear as a method of information sharing rather than Darwinian evolution, new questions arise that might better be addressed by intelligent design theory: is there a reason for this kind of information sharing? Could it be a designed mechanism gone awry? What other processes of information sharing previously attributed to Darwinian evolution do we not know about yet? And how could the new paradigm lead to better strategies against the ‘superbugs’ that are becoming resistant to our last-resort antibiotics?One thing is clear: indiscriminate use of antibiotics is causing a crisis, and new approaches must be considered. Another clear lesson is that Darwinian evolution is not as clever as thought.In the cemetery of fallen Darwinian arguments, we can erect a new headstone: “Here lies antibiotic resistance as proof of evolution.” The cemetery is getting pretty crowded. Like we say, if you hear a Darwin debater offering indisputable proof of evolution, just wait awhile. It will fall. Creationists will be ready with their shovels to bury it alongside so many other indisputable proofs of the past: Haeckel’s embryos, Piltdown Man, vestigial organs, sexual selection, the horse series, human evolution – all the classic icons of evolution. Some are long dead; others are in their last dying gasps. What we can’t stop is the Zombie Apocalypse! Read Jonathan Wells’ new book Zombie Science for explanation. You can also hear Dr Wells on ID the Future and see his writings at Evolution News & Science Today (search on ‘zombie’). The book has a whole chapter (ch 8) debunking antibiotic resistance and cancer as evidences for evolution. (Visited 610 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

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Ind vs WI: Dhoni defends decision to opt for a draw

first_imgIndia captain Mahendra Singh Dhoni defended the decision not to press for a win in the third and final Test against the West Indies here, saying that his side could have lost the match while going for the target.India, who had already taken 1-0 lead in the three-match Test series, were 94 for three just before the start of mandatory 15 overs while chasing 180 for a win before Dhoni decided to end the run chase.”Not disappointed about stopping the run chase. We were risking a series win going after the target. We realised that it was not worth going for it after those wickets, we gave it a go but we are happy with the series win,” Dhoni said after the match at the Windsor Park on Sunday.”We did well in this game. West Indies batted well actually, we are not disappointed in any way,” he said.West Indies skipper Darren Sammy said he was a bit surprised that India opted not to press for a win.”I was a bit surprised that India ended their run chase but we will take it. We are very happy with the draw,” he said.Talking about the pitch and India’s team composition, Dhoni said, “We were not sure about the wicket. If we go with a 2-2 combination and the track turns out to be flat, that can be a problem. We knew we had bowlers who could spin the all if it started taking turn, like Raina.”Harbhajan was getting a bit of spin and bounce and he got valuable wickets, not much help for the fast bowlers, they did well,” he said.advertisementDhoni said the series was a good exposure for youngsters and he felt good to see Ishant Sharma take responsibility.Ishant, Man-of-the-Series for his 23 wickets, said, “This is my first series where I took the highest wickets. It’s kind of an Indian track, slow and flat, but you have to put in the effort as these things are beyond your control. I am pretty confident about myself, looking forward to England.”Man-of-the-Match Shivnarine Chanderpaul said, “The whole series I was getting out in 20s and 30s, very happy to carry on past the three-figure mark. It’s at the back of my mind it has been happening for a while now.”It’s always an honour (becoming the most capped Test cricketer for Windies), just shows what hard work can do for you,” said Chanderpaul who scored unbeaten 116 in West Indies’ second innings to deny India a victory.- With inputs from PTIlast_img read more

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