Amino Acids & Evolution

[J_B_]

As I said, my experiment was a failure. Still, I hope we can discuss amino acids and evolution.

Specifically, how important is it to evolution that all known life is composed of ~20 amino acids when many, many more form naturally?

I've seen this fact claimed as evidence in support of evolution, but I don't see how that is. I'm not saying it refutes evolution. And supporters will find plenty of other ways to make their case. Nor am I saying it's not important to understanding biology. I'm sure it's very important to know why a particular amino acid is present and how that affects life. I just don't see it as supporting evidence for evolution.

So, this is not a prove/deny challenge. The question is: How important is ~20 amino acids to the corpus of evidence used to support evolution? If it were shown that it doesn't support evolution, would it really make any difference?

 

[Occams Barber]

As I said, my experiment was a failure. Still, I hope we can discuss amino acids and evolution.

Specifically, how important is it to evolution that all known life is composed of ~20 amino acids when many, many more form naturally?

I've seen this fact claimed as evidence in support of evolution, but I don't see how that is. I'm not saying it refutes evolution. And supporters will find plenty of other ways to make their case. Nor am I saying it's not important to understanding biology. I'm sure it's very important to know why a particular amino acid is present and how that affects life. I just don't see it as supporting evidence for evolution.

So, this is not a prove/deny challenge. The question is: How important is ~20 amino acids to the corpus of evidence used to support evolution? If it were shown that it doesn't support evolution, would it really make any difference?

Here - look it up for yourself
amino acids reveal evolution - Google Search

OB

 

[J_B_]

Here - look it up for yourself
amino acids reveal evolution - Google Search

OB

I have.

 

[essentialsaltes]

Specifically, how important is it to evolution that all known life is composed of ~20 amino acids when many, many more form naturally?

I'm not sure 'importance' is the right word. But, what it does seem to suggest is that all current life on earth is related through common ancestry. If life had originated independently multiple times on earth, then other 'versions' could have used any of the available amino acids, which you rightly note are very numerous. Or some other kind of biochemistry entirely.

But the biochemistry of codons and amino acids of every living thing on earth is pretty much the same.

---

Turning the question around, if every species was specially created, why did the designer restrict herself to this small subset of amino acids, when she had a huge toolbox at her command?

 

[J_B_]

I'm not sure 'importance' is the right word.

It's what I want to know. Would a biologist consider this ground that can't be conceded without conceding evolution? Or would they shrug and say, "Yeah. Maybe." I suspect the latter is more likely.

But, what it does seem to suggest is that all current life on earth is related through common ancestry. If life had originated independently multiple times on earth, then other 'versions' could have used any of the available amino acids, which you rightly note are very numerous. Or some other kind of biochemistry entirely.

When briefly stated, this argument boils down to "correlation is causation", which is not defensible.

However, in all fairness, the discussions I've had on the matter in the past expand the argument. They admit the possibility of multiple origins. But, through competition, predation, environment, etc. our ~20 version is the only one that survived. These arguments come as various versions of Crick's "frozen accident" argument.

Again, though, by whatever means this happened, the argument then boils down to saying conditions (random though they may be) favored our "version". If conditions favored the ~20 we see, then they would favor any multiple origins (if they happened) of those ~20. To try to argue the conditions favored only one population of our particular ~20, while at the same time admitting multiple origins, becomes special pleading.

It does seem at least a few biologists are beginning to consider other possibilities as in here: The Alphabet Soup of Life, if I'm interpreting the article correctly.

Turning the question around, if every species was specially created, why did the designer restrict herself to this small subset of amino acids, when she had a huge toolbox at her command?

I don't know. Since this goddess of yours hasn't spoken to me, I wouldn't speculate on her motives.

 

[Tolworth John]

How important is ~20 amino acids to the corpus of evidence used to support evolution? If it were shown that it doesn't support evolution, would it really make any difference?

The amino acids needed to create life have to be pure, not contaminated and all to be ' left handed '
Amino acid can form naturally but they are a mixture of left and right handed as well as being mixed with other amino acid.
Evolution supportors have not explained how they get pure left handed amino acids, all twent of them and explained how they are mixed in the right quantities and right order to make the protins required to create cells .

Is this important? No practical way to show that natural processes can do the above means evolution cannot even get started.

 

[essentialsaltes]

The amino acids needed to create life have to be pure, not contaminated and all to be ' left handed '

Non sequitur.

Just because we use left-handed ones does not mean that right-handed ones cannot be present. The presence of poisonous berries does not make it impossible for humans to consume edible berries.

 

[Tolworth John]

Non sequitur.

Just because we use left-handed ones does not mean that right-handed ones cannot be present. The presence of poisonous berries does not make it impossible for humans to consume edible berries.

So you say, unfortunetly chemical biologist say the purity is important.

 

[essentialsaltes]

So you say, unfortunetly chemical biologist say the purity is important.

Can you quote such a chemical biologist?

 

[Semper-Fi]

-the-improbability-of-evolution
World News, Economics and Analysis Based on Bible Prophecy

 

[Bungle_Bear]

-the-improbability-of-evolution
World News, Economics and Analysis Based on Bible Prophecy

Yeah, no. Argument from incredulity and lack of understanding is not convincing.

 

[SelfSim]

-the-improbability-of-evolution
World News, Economics and Analysis Based on Bible Prophecy

I was gonna let it slide, as the numbers arguments presented there, all assume random processes, (which is complete junk chemistry and is very widely known as being such).

Zooming in on their closing, bogus argument about the chirality preference, the mainstream Collective Autocatalytic Set (CAS) hypothesis notes that homochiral polymers, DNA, RNA, or polypeptides are either more stable, or function better than racemic polymers.
This suggests that collectively autocatalytic sets of such homochiral polymers, would be selectively advantageous to the Collective Autocatalytic Set as a whole. In fact, I've seen it argued that racemic mixtures produce ligation and cleavage reactions, which then makes them make less functional racemic peptides.

The end result is that homochirality is a prediction produced from the Collective Autocatalytic Set reaction hypothesis .. which is way more useful than one that doesn't .. namely because we already know life is based on homochiral bio-molecules .. (duh!)

 

[SelfSim]

For those interested, I just posted a recent update on a tested (ie: demonstrated) pathway leading to the formation of RNA molecules in the Science Forum thread on abiogenesis hypotheses, here.