Lenski’s Long Term Evolutionary Experiment
Richard Lenski began the LTEE with 12 populations (six $Ara^+$ and six $Ara^-$) of the bacterium Escherichia coli on 24th February, 1988. The experiment is currently housed at Michigan State University and has run continuously apart from a short break while relocating to the present site and another during the height of the Covid-19 outbreak.
The method is very straightforward. Each 24 hours, from flasks of the bacterium in a growth medium known as Davis minimal broth dosed with glucose at 25 mg per litre (DM25), are extracted by pipette a random sample of 0.1 ml which is added to a new volume of 9.9 ml DM25 in new flasks which are then incubated at 37°C for 24 hours and the procedure repeated indefinitely.
What the experiment does is to provide a consistent, stable and simplified niche for the twelve lines allowing them to proceed in parallel isolation (great care is taken to avoid cross-contamination). This allows the researchers to test whether evolutionary change is inevitable, repeatable or unpredictable.
One objection often made by critics is that, being designed, the experiment is not a true test of natural evolution. But Lenski chose the environment, he does not design the bacteria. A random (the flasks are continuously agitated on a mixing plate to ensure uniform distribution of cells) sample makes it through to the next generation (70,000 and counting in the thirty years the experiment has been running) but, over time, the twelve lines have undergone changes that can be observed. Cells have become larger, redundant (in the experimental niche) parts of the genome have become broken.
The most spectacular change so far has been the arrival of the ability of one line to metabolise citrate aerobically. The change has been well-studied because deep-frozen samples are retained every 75 days and DNA sequences (thanks to cheaper and quicker DNA sequencing) can be compared to match genomic changes against phenotypic changes. The ability to digest citrate involved changes at more than one locus, a beautiful illustration of neutral evolution and genetic drift.
The LTEE also is an excellent refutation for Creationist John Sandford and his “Genetic Entropy” idea. I’m sure others can point out errors but this OP is meant only to provoke discussion and not to be authoritative so please jump in with comments.
Hmm. Yet here we are along with all the rest of life on Earth. And 4 billion years ago there was no life on Earth. So what happened?
Sure, he’s the world expert, arguably, in synthesizing graphenes.
Many things appear to be beyond your comprehension, nonlin. Tant pis.
Not a single texbook says that the abiogenesis experiments got life out of the Miller-Urey or any experiment like that. Not one textbook. Not a single teacher ever told me that any experiments à-la-Miller-Urey got life out of those flasks. Not one. Not in elementary school, not in middle school, not in high school, not at any university level. I teach at university, both undergraduate and graduate levels. I myself never say such a thing. That would be dishonest, and I prefer to leave the lies to the likes of you and Tour.
It’s amazingly naïve of you to think that because the public believes something, it must be because it is taught, as if you weren’t enough proof that what’s taught is too often lost on the students. That if the supposed survey is real, who can know? If Tour lies about things I know, why should I believe anything else he says?
But that doesn’t follow. Religion is definitely a business even though there are no gods.
Entropy,
The survey exists, but it has some problems.
The respondents are self-selected, by and large unemployed, and motivated to inflate their self-reported educational level. There’s a missing question that may well cause framing and/or selection problems.
If nonlin is “scientific”, then he will provide the details to explain why the results are still valid. I bet he won’t.
Nonlin has too much trouble understanding half the words in a sentence (I’m serious). I don’t expect him/her to be able to explain anything at all.
To Nonin life from Miller-Urey was taught to those people at every level in their education, and that’s that. No verification needed.
Tour, like Hovind and others, are very good liars and rhetoricists. They know that if they tell half lies, the public will believe them the whole thing. For example, Tour mixes and matches the “primordial soup model” with “Miller-Urey got life coming out of those flasks”, so that those who might half verify will see that the primordial soup model is explained and assume that to mean that it is taught that Miller-Urey got life from their experiments. They will fail to notice that the textbooks talk about it as a proposed model, not as a result from any experiment, and will further fail to see that the textbooks quickly clarify that the models are far from confirmed. Those notes of caution will be lost as soon as the curious sees “primordial soup” mentioned. That will mean, to them, that it’s us who’re lying about what’s taught, no more reading needed.
Lying like those creationist-snake-oil-salesmen is an art.
But an art long recognized as such. There’s a reason why witnesses are told to tell the truth, the whole truth, and nothing but the truth. This is to prevent outright bald-faced lies (tell the truth), don’t leave out details which by omission spin the nature of what you’re saying (the whole truth), and don’t mix some lies with some truths to paint a false picture (nothing but the truth). And still we value cross-examination to bring out facts that are omitted, misrepresented, or glossed over.
A gifted liar’s presentation is generally almost entirely true! As an analogy, consider almost any novel, where the setting is accurate, some of the characters actually exist (or existed), and the plot is entirely plausible. It doesn’t take much fiction to make a novel fictional.
Did you even bother opening the link to the actual survey? No, of course not. Nothing more is expected from the guy that adds alleles.
Thank you. Now, why not go full honest and admit the results are to be expected given atheists tell lies all the time?
And you can’t chalk it up to stupidity over and over. Take this guy that insists earth was “observed” 4 b.y.a. An obvious falsehood. So obvious that said falsehood cannot probabilistically be stupidity.
And take “LTEE” with its preconceived “evolution”. But not one of you can tell what the null hypothesis was on that experiment. That certainly must be dishonesty, as ignorance can easily be corrected by just thinking through this problem.
And on and on and on. Tour goes through a list of atheist lies in that video. Of course that doesn’t even begin to scratch the surface of the mountain of lies atheist tell to the public.
I didn’t run the survey. Don’t like it? Do your own.
But, like I said, I used to believe the Darwinist lies, just like those folk. So there. My survey of one.
Nonlin.org,
You are quite correct. The survey has nothing to do with whether or not respondents ‘believe a lie’, which is a mere assertion on your part, lampooned on mine.
I know. Counting instances is outrageous. Who would do such a thing? It’s almost like something one might do in … a survey! 🤣
https://en.m.wikipedia.org/wiki/Earliest_known_life_forms
If you reject fossils as evidence that micro-organisms were around 4 billion years ago, fine, put another date on it. I was simply making the point there was a time when Earth was sterile. It isn’t now. Ergo life on Earth began. Abiogenesis happened. What are you objecting to?
Tour fails dismally in understanding current hypotheses for abiogenesis. A warm little pond doesn’t figure in any of them. What’s with the atheism frothing? I thought you were arguing the science.
Yes, you do appear to be on your own. Tant pis.
Alan Fox,
“So much urine”, in Franglais. Another schoolboy aside: I can’t take Tour seriously while he looks like Parker from Thunderbirds.
Yes, Nonlin obviously is quite anxious to discuss the “science”:
Emphasis mine.
The irony of being accused of lying and dishonesty by someone who casually conflates abiogenesis research with atheism for rhetorical purposes is so thick you could out a fork in it.
No, it is much worse than that. nonlin really meant 4.5 bya.
Back when he was arguing that solidification required a fridge, nonlin ridiculed the idea that the entropy of the earth decreased when the mantle solidified.
He is disputing the claim that the earth used to be hotter.
Although I am curious: nonlin refers to “…opening the link to the actual survey?” What link, nonlin? Tour’s video provides a link to the academic’s CV, no more.
DNA_Jock,
I was amused to note that 2 paragraphs of mine constituted ‘War and Peace’! I do go on a bit sometimes, but that wasn’t such an occasion!
That wouldn’t be honest:
1. Most teachers are not atheists.
2. No teacher tells students that Miller-Urey got life out of their experimental flasks.
3. No textbook tells students that Miller-Urey got life out of their experimental flasks.
4. I teach at University. I’m an atheist. I don’t tell students that Miller-Urey got life out of their experimental flasks.
Did you get it now you illiterate and irrational buffoon? Do you need that in terms a kindergartener could understand instead? Too advanced for you?
———
P.S. Well, since the simple act of counting is unbelievable to Nonlin, anything will be too advanced.
Once again, I’m reminded of Dawkins writing “there is no sensible limit to what the human mind is capable of believing, against any amount of contrary evidence….no evidence, no matter how overwhelming, no matter how all-embracing, no matter how devastatingly convincing, can ever make any difference.”
nonlin is our local illustration of this principle. Religion seems to have the power to do this, but religion doesn’t have a monopoly. According to latest polls, 73% of Republican voters are STILL convinced the election was rigged, and it’s not for religious reasons. We’re in the post-truth, post-honesty age. Perception rules, and facts aren’t relevant. When your mind is made up, your facts are too. Convictions not based on evidence cannot be countered with evidence. You can be probably correct or you can be absolutely certain, but you can’t be both. And so on (and on and on).
Robert Silverberg suggested (in a slightly different context) that if you had the power to suck all the religion, and all the religion-based idiocy, out of nonlin, all you’d have left is an empty husk suitable only for hospice care.
Since I’d guess you want to get off the bad taste of Tour rhetorical bullshit, maybe you’d like to watch this PBS video:
The Genes We Lost Along the Way
Every time I see Tour rant I think of Harpo Marx making his “Gookie” face.
https://i.imgur.com/2vRm5JC.jpg
http://theskepticalzone.com/wp/wp-content/uploads/2021/02/gookie.jpg
Your whole train of thought (?) is a wreck. A train wreck.
I am arguing science. Only no one else replies science. Take the null hypothesis on LTEE. It doesn’t get more science than that. Why no takers?
And your source is…? At least little monkey counted people. But poor sap doesn’t know the difference between people and alleles. What do you expect? Give him a cucumber anyway for the effort.
100% social science. Granted, social science is not much of a science.
Let’s de-conflate then, shall you? What would you say the overlap between atheism and abiogenesis support is? 99.9%, 98.9%? Social science all the way!
Let’s analyze: why do people believe a lie? Namely that abiogenesis has been achieved? Do a search by abiogenesis and tell me what comes up. Miller-Urey? ” Abiogenesis is the creation of organic molecules by forces other than living organisms”??? “The origin of life from nonliving matter”?!? Hey, it’s a done deal according to Google’s satanic algorithm.
Yet little monkey claim he’s not pushing that link. But why is Miller-Urey in a biology text book anyway? Some guys get some chemicals. Is that biology? Or hype? BE HONEST! Can you?
The quote doesn’t support your assertion. I’ll be generous and chalk it up to your ignorance. Strike one. Nah, just kidding. Maybe strike 1001.
Another nameless dummy believes his religion is not religion. How retard is that? Judging by the massive dark hole retard he cites, not retard enough.
Now back to the science. LTEE null hypothesis is…? The link between “evolution” and genetics is…?
In the case of the LTEE, the null hypothesis is that relative fitness in all twelve tribes would remain unchanged.
That’s not the claim. It is observed there is life on Earth. There is evidence, indirect admittedly, of life on Earth 4 billion years ago. Not long before that, Earth was sterile. Abiogenesis hypotheses are attempts to explain how that happened. Unfortunately there is only one data point, currently.
You would have to remember the context. You claimed that “cooling crystallization” (your option 2) required a fridge.
You wrote:
I made fun of this by referring to the earth’s mantle 4.5 bya.
Sad that you cannot even remember the rubbish that you write.
From the guy who cannot agree with himself!
🤣
No, you’re not. Your unsupported and contradictory claims are not science, are, at best, fallacies.
People cannot get to the science unless you can agree with yourself. I have answered by explaining the logic and the science to you and you blatantly ignore all of it. Of course I understand why you ignore all of it: you’re too incompetent to understand any of it, and too dishonest to admit that everything goes way above your head.
You’re not discussing science, you’re trying to impose your views on everybody else, blind to your deep problems. Agree with yourself, then try understanding the science, then answer coherently and calmly when corrected. Make sure you understand before yelling at everybody. Mainly, try and keep yourself honest.
That’s an incoherent question. The LTEE experiment has an exploratory design, not an hypothesis-driven design. The distinction is learned in preschool experimental design. How can you claim to discuss science if you don’t know such foundational distinctions?
It’s the interesting observations in the LTEE that can then be subjected to hypothesis-driven design and analyses.
That was about science. Let’s see you ignore one more answer about the science. Let’s see you learning nothing from it, as always.
You’re shooting yourself in the foot. You believe in the magical being in the sky little monkey. Always remember that. Beam in thy own eye.
Who the hell knows. Maybe they don’t care one way or another and answered whatever came to their minds.
Nice attempt at a dodge. A tad ironic though. The claim is that we teach, at every school level, that experiments à-la-Miller-Urey got life out of their experimental flasks. That’s a lie. Do you want honesty? Start with yourself. The beam in thy own eye you poor baboon.
Ironically, your search results don’t support your claim anyway, making you unproductively dishonest:
None of those say that Miller-Urey got life out of their flasks Nonlin. I know you’re illiterate, but here you’re demonstrating my point: that it’s you who feels the deep need to lie. Here you are, either lying, or being the usual illiterate, or both. I suspect both.
Holy crap. Besides an illiterate liar, you’re a religious nut.
Because the experiment got, for the very first time, organic complex molecules from simpler ones under some conditions where nobody knew that would happen. Because that was a huge achievement for times when people thought that wasn’t even possible. Because that’s a classic experiment in the search for scientific answers to the origin of life.
The right question would be: can you Nonlin? Can you be honest?
It’s about experiments attempting to figure out how life started. Life is the subject of biology you poor moron.
Answered already.
Sorry, but this is not a scientific question. This is nonsense. Genetics and evolution are irremediably linked. It’s a done deal. They’re linked whether we wanted them to be linked or not. So it’s up to you to explain why you think there’s no link. We have asked you a million times and you refuse to answer. Then, hypocritically, you complain that nobody answers your “scientific” enquiries. Start with yourself you little, tiny, inconsequential, simpleton. Show us by example. Give us a well thought, succinct, respectful, coherent, explanation as to why evolution has nothing to do with genetics.
I won’t wait standing though. If you cannot agree with yourself, we cannot expect coherence in your comments any time soon.
Alan Fox,
It’s exploratory research.
Indeed, I read your comment. Using “expected” in its everyday sense, results may have been expected but there was no specific hypothesis being tested. I did search a little before commenting but…
Regarding the LTEE, what was observed was an increase in relative fitness: figure from this paper
There is a paper here that explains how Lenski et al. measured relative fitness for the LTEE.
ETA I was going to quote something from the paper but it is so information-packed, clearly written and concise that I defy anyone not to get the gist by reading it.
Mea culpa. I mixed up Sandford and Spetner. It is indeed Lee Spetner that Joe G admires rather than Sanford. Apologies to Joe G.
It’s kind of like the link between sunrise and astronomy. If you look real real closely, there IS a link there somewhere.
I like Flint’s analogy regarding how astronomy is connected to heavenly bodies. It boggles my mind that someone can ask, apparently seriously, what genetics has to do with evolutionary theory. Nonlin, think about this. What gets inherited from parent to offspring?
My guess is that the proportion of atheists (or representatives of any religion for that matter) among abiogenesis researchers is similar to that of the scientific community at large.
Since you have suddenly become so fond of social sciences, could you let me know what you think the overlap between creationists and believers is? Would 100% be an accurate guess?
You tell us. You are the creationist.
Entropy answered that already. Briefly, the experiment was a test of the Oparin-Haldane hypothesis that postulated that conditions on early earth favored the spontaneous synthesis of organic compounds. Had you actually read those biology text books, you would have known.
Odd that you have such a strong dislike of the Urey-Miller experiment. I thought you liked empirical science. But whenever someone gets a result you don’t like, you get all upset. Why is that? And …. be honest.
Perhaps someone will bother explaining to you* why this is a nonsensical question if you first put some effort in yourself. Can you tell us in your own words what the purpose of the LTEE was? Alan posted loads of links with the answer in.
This has been answered many, many times. Most definitions of evolution even have the word “heritable”, “genetics” or “alleles” in, so your refusal to acknowledge this link is just stubborn denialism from your side. If you don’t like that, then let us know what you think evolution is.
Personally I think you can’t, because you have no friggin’ clue nor interest in what other people understand evolution to be.
* ETA: apart from Entropy 😀
No, he covered them both. He referred to Spetner by name, but referenced Sanford by invoking ‘genetic entropy’.
I do wonder what version of “evolution” nonlin once espoused, if it had no heritable component. It doesn’t speak particularly highly of one’s intellectual capacity to admit to such.
But this is the heart of the problem: rejecting a strawman; arguing against something no-one proposes. Whatever nonlin means by the invariably-scarequoted “evolution”, it can’t be the thing anyone else understands by the term, if it has no heritable component; no link with genetics. It’s like someone saying “I hate cats. Trunky, leafy bastards they are, shoving their roots under my foundations. Damn cats”.
DNA_Jock,
It remains chucklesome, in both parts. Solutions don’t evaporate spontaneously unless you heat them up; liquids don’t solidify unless you put ’em in a fridge.
Allan Miller,
OK. I do recall him going on about Sanford and his gene gun. Joe is insisting now neither Spetner nor Sanford are his heroes. Glad we got that cleared up.😏
Alan Fox,
He’s a fickle bastard!
Really? After I wipe the kitchen table with a wet paper towel, the water that is left on the table somehow disappears in the next hour. How does that happen if it is not evaporatting?
Joe Felsenstein,
Latent heat of evaporation has to come from somewhere. When I were a lad and pints of milk were left on the doorstep, posh folks had porous pottery coolers that would keep milk cool by evaporation of water in the dish that the container sat in.
Allan was not being serious, Joe; he was ridiculing nonlin’s claim that evaporation (and the resulting crystallization) does not occur spontaneously, just as I was ridiculing nonlin’s ‘solidification requires a fridge’.
Yes, Alan, there is something else going on with the evaporation, but let’s not confuse the poor kid.
I’m not sure it is within our power to reduce nonlin’s confusion.
Whatever that means…
Anyway, “evolution” is not part of the hypothesis which means is an assumption which also means it cannot be an outcome of the experiment. IOW, following the scientific method, LTEE cannot prove “evolution”.
Wait a minute. “Indirect evidence” is not the same as an “observation”. No wonder the people believe all kind of blatant falsehoods. Because they are lied to.
I do remember the context. This is FALSE:
I ridiculed your appeal to something happening 4 bya (of which you know basically nothing) instead of an experiment we can run here and now. Perhaps you don’t understand what you read. Or you’re willfully ignorant.
In other news, “evolution” and genetics are linked by decree of little monkey. Figures.
Exploratory research, huh? LIKE the MTEE I run (yep, that’s Medium Term Evo Experiment): take some TSZ crash dummies, let their train of thought turn into a train wreck and enjoy how they disprove their own belief in “evolution” by smashing against each other and the unyielding reality.
As I was saying. What Lenski tells us is: “Fitness, however, is often difficult to measure [read ‘impossible’], especially for long-lived organisms.”
He goes on:
“Thus, researchers typically measure fitness components—such as the number of seeds produced or offspring fledged—and use them as proxies for fitness.
…
One commonly employed method of quantifying microbial fitness is to calculate the maximum growth rate”
IOW, “there’s no fitness folks. Lenski just measures offspring and rate of growth” Straight from the Lenski’s mouth! Train wreck I tell you!
Not “evolution”, right?
The number, Corneel! What is the number? Your best guess. and go both ways (% of A in B and % of B in A). Sorry, should have clarified.
Since you yourself are a believer in the evo fairy tale, I’d say everyone believes in something. Makes sense? If not, show me a person that doesn’t believe in anything.
But there’s no biology in Urey-Miller, correct? And many organic compounds can be synthesized “spontaneously”. But you’ll never admit Miller-Urey is just a big ugly lie. Not an outright lie. But a lie nonetheless.
To make “evolution” look legit despite the evidence. Crash dummies galore.
I don’t deny that part. Which is parasitism, not a link if the other side doesn’t reciprocate. But genetics has absolutely no need for “evolution”. Why do you deny that evidence? So no link, see?
DNA_Jock,
You keep making false claims long after you lose the argument and then “cite” some nonsensical comment, preferably yours too. It seems you are fooling some people. Only not who you think you do. Hilarious!
In the meantime, another confused and belligerent creationist attempts to defend a claim I dismantled before.
(It’s a tad ironic that this furious rant comes from a blog called “Intelligent Reasoning.”)
Quelle surprise! A failure from the very title. Selection is not the same as the source of the variation over which selection happens. Mutations can happen for a number of reasons: failures in replication, exposure to different kinds of radiation, and each of these might have biases. It’s because of potential biases that I’d prefer not to call them chance events.
I’d imagine that thinking about the phenomena is better than adhering to a few quotations from some known biologists, as if the issue was about pronunciations, rather than about the phenomena. Yet, Joe G goes for the pronunciations, and not too well.
A bit misguided. Still, I don’t see here a single reason to think that Darwin claimed that variation had to be due to “chance events,” or else natural selection would not happen.
Oh, right, because science must be like religion, a matter of pronunciations by some key figures, rather than thinking and describing phenomena, with improved understanding as more data is gathered and analyses performed.
Even then, Joe G failed to see an “almost” and an “except”, which clearly show that, even back when Ernst wrote that, mutations were not “mandated” to be chance events. What’s with furious creationists and illiteracy?
So?
So?
Radioactivity is a telic process? I thought radioactive isotopes were just unstable. We learn something new everyday.
This looks much more like some creaTARD has trouble distinguishing “chance” from “non-telic”, and fails to read words like “almost” and “except”, or maybe doesn’t understand the meaning of such words.
Yep. Pathetic. Only not in the direction Joe G imagined.
I know you’re an illiterate, so I should not be surprised that this concept causes you trouble. Yes. Exploratory research. Look it up if you have the ability.
Incorrect. Again: it’s an experiment aimed at understanding the origin of life. Guess what’s the subject of biology! Yes! Life! Did you get it now? Too advanced for you?
But this wasn’t known when the experiment was carried out simpleton. That was a later discovery. Do you understand the concept of historical context simpleton? Too advanced for you?
You have to do better than that, though that would be impossible for you. What’s a lie exactly? They did get those complex molecules out of simpler ones. Not a lie. It was later found that this happens all the time, confirming the experimental results. So, again, what lie simpleton? Your lack of understanding of historical context and of the relevance of their results don’t make them a lie. It makes you an ignorant illiterate buffoon, but the experiments got what they got and remain relevant. You see it as a lie because you’re used to lie, and therefore you imagine that everybody is just like you, but you’re wrong simpleton. Your need to lie doesn’t make everybody else a liar.
This must be the lamest excuse ever to insist on your stupid claim that there’s no link between evolution and genetics. Reciprocity is not required for there to be a link. Even if it was parasitism, that’s still a link you poor dishonest-lame-illiterate buffoon.
However, instead of a firm, if lame, excuse, this is just failure in your understanding. Genetics is not just about hereditable characteristics and their underlying molecular carriers. Genetics is also about how the hereditary material changes. It’s distribution across and within populations. After all, tere’s a field of genetics called “population genetics.” In other words, evolution and genetics feed each other because they’re inseparable conjoined twins.
All this time I thought you believed that everything was created by some magical being in the sky, and now you believe that some monkey is behind the fact that organisms inherit characteristics from their parents via genetic material.
Given all of your incoherence, I’m not surprised of your incompetence to discuss the science. So, keep running from it little monkey!
Yet, remember, as some simpleton said before:
Joe Felsenstein,
Sorry, yes, as Jock notes, I was ironically representing nonlin’s position, not my own!
You make an outrageous claim but I have to provide the numbers to disprove it? That’s rich.
Let me indulge you though: Being really conservative, I’d hazard a guess that less than half* of all researchers on abiogenesis are atheist. And to go both ways; The proportion of researchers on abiogenesis among atheists must be tiny, say less than 0.01%. Why did you need the latter figure, I wonder?
*That’s 50% folks.
Oh good, word games. Did you really misunderstand what I meant with “believers” or were you avoiding the issue that all creationists happen to be theists? Be honest.
Wrong. Let me introduce you to a whole new concept: Biochemistry. You sure live and learn, don’t you?
Will you hazard a guess what living organisms are made off? Can you guess what the relevance of spontaneous synthesis of organic compounds is for abiogenesis research? Take your time, we’ll wait …
How unfortunate. Wrong again. Try again. This time you may want to open the links that Alan sprinkled all over this thread.
Stop the presses! Ladies and gentlemen, Nonlin has conceded that genetics is relevant for understanding evolution!!!
Do you know whence the quantitative genetic models come that are used in animal and crop breeding?
The “previous posts” sidebar made me laugh:
I can’t imagine why. 😀
Corneel,
I don’t think you were here when he was here. It was a treat.
Crap!
Did you notice that Joe G said he never contradicted anything he said, but he edited his post!
Originally, Joe G wanted to minimize the finding by claiming that things “just happened”, contradicting his own claim that there’s no evidence that the mutations were chance events:
So who’s the pathological liar?