I don’t think that my brain can quite process it on the layman’s level, which is one of my goals here, but I believe you. Is this compound produced with the right chirality?
I’m not sure I understand your question. Can you explain what you mean by “the right chirality”?
They say that every molecule in a living system is left-handed, but every molecule that nature produces abiotically contains an even mixture of both left- and right-handed versions. The more complex a molecule, the more branching points it has, and at each branching point it can decide to go left-handed or right-handed. So if a molecule, that has three branching points in its structure is produced abiotically, then the end result of the reaction should be an even mixture of 2x2x2=8 different versions of the same molecule that have the same chemical formula are mirrored compared to the others at one or more of the possible branching points.
I’d better let @jordan take a look for sure, but I don’t think the model depicts enough precision to note the chirality. In any case, the chirality question is of little relevance to the point being made.
I find this whole episode quite sad. There is no argument that Tour is an outstanding and highly accomplished scientist in his field. Unfortunately, he has apparently gone far from his field without having appropriate conversations with colleagues. If he was simply convinced that ID is a better explanation than evolution for what we see in living organisms today, I wouldn’t be thrilled, but would accept it and move on. But what he did in that video - slandering a Nobel-prize winning scientist and accusing him of lying, giving too little care for accuracy and precision, and pandering to his audience of lay people - was extremely bad judgement that reflects poorly on him, Rice University, and Christians in science.
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That’s right, the Szostak image doesn’t show any 3D structure at all. I do think homochirality is a largely separate issue from initial synthesis. I believe usually you either start with a chiral starting material (which only affects the product chirality, not the reaction itself) or you generate enantiomeric excess after the synthesis.
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RNA is a left-handed twisted helix. If the precursor molecules to RNA are a mixture of different handedness, then they cannot build a proper RNA chain, meaning that the reaction that was shown on the graph in the article about origin of life is of little relevance to the origin of life.
Wow, you’re really reaching for any reason to excuse Tour’s disingenuous and unprofessional attacks on Szostak’s work, aren’t you?
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I think this really narrow focus/attack on dr. Tour’s comment regarding this graph’s author while basically ignoring the rest of his talk merits an equally narrow focus on the graph’s merits.
His talk has no merits. It is a protracted argument from ignorance, with a healthy dose of slander thrown in.
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It doesn’t always work that way. Sometimes it only takes 1 chiral precursor to induce chirality in the whole thing, it’s not just a random heads/tails process.
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Would it be correct to say homochirality could just be a “frozen accident”?
This was one of the things dr. Tour was railing on, so I thought it was worth mentioning.
Why was this reply hidden? It’s on topic and doesn’t mention anyone posting here.
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None of his audience, including the chemistry professor present seems to have thought so at the time, even when he/she was specifically asked for a comment. This was a controversy created after the fact. It’s a perception. If I said 99 things that are true, and one thing that was perhaps wrong would I be called something nasty too? Depending on the circumstances, the answer is yes. Slander is a base instinct we have, and it comes out when we feel threatened. No mystery there.
The audience was virtually 100% Christian fundamentalists there to listen to attacks against evolution and OOL. You really expected any of them to question the propaganda they came to hear?
So you say Tour felt threatened when he slandered Dr. Szostak with the baseless accusing Szostak was lying?
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Because we feel threatened by persons, it would have to be a persistent longstanding pattern of slander against a certain individual. That’s why I said earlier in this thread that that I would need to see repeated verbal aggression on the part of dr. Tour towards dr. Szostak in order for me to accept that this incident was the result of malintent. sort of like how a certain individual is constantly railing against dr. Tour.
No, dr. Tour used the Nature article as a one-time example in service of a larger point he was making, and probably have forgotten about it afterwards, just like I did. The way I see it, it could’ve been any other professor publishing in Nature, and dr. Tour would’ve reacted the same way, just because of the kind of person he is.A very driven researcher for sure, no matter the subject at hand. This whole incident has more to do with dr. Tour’s personality and interests, than with his religious beliefs. The split could be 51%/49% though.
Wow. Your defense of Tour sounds a lot like Trump fans trying to defend Trump’s compulsive lying. BTW Tour has been making anti-science propaganda videos attacking evolutionary biologists and OOL researchers for some time now since he joined the DI. This one isn’t the first.
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Actually I’m here for the science, but y’alls keep asking irrelevant questions. Especially with the molecular tools that became available in the last 5-10 years, we could prove evolution on the molecular level for the first time in history! That’s why i wanted to know more about the role of chirality, because the way I heard, it is the greatest stumbling block in the way of oolr.
To the extent you are correct this is a valid point.
Neither @cwhenderson, @jordan, or myself have railed against Tour. Jim is a personal friend of mine, and I do not relish any of this.
To give you some perspective, this what I have written in the past about him, read this.
Yes, the atheists here are going after him. I think it substantially undermines their point, making them seem less trustworthy. In their defense, in the same way you feel defensive of Tour, they feel defensive of Sostack. No one makes progress when adrenaline flows.
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