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Author Topic:   Is ID falsifiable by any kind of experiment?
Percy
Member
Posts: 22668
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.5


Message 490 of 507 (911024)
06-02-2023 8:08 AM
Reply to: Message 489 by sensei
06-02-2023 4:11 AM


sensei writes:
Yes, I agree. That is why UCA seems to be the only viable option for science to consider. If UCA fails, we need to reconsider our origins.
Even though everyone on the planet is descended from a single man or woman, that man and that woman (who did not live contemporaneously) were not the first man or woman, and there were many other people alive at the same time. They just happened to be the only man and woman who left descendants alive today.
In the same way, UCA was not the first life. It lived within a thriving community of life, probably widely varied with many species and genuses and so on. It was just the only life that left descendants.
For there to be multiple UCAs there would had to have been more than one independent origin of life. This is certainly possible, but only one of these origins of life left modern descendants given the relatedness of all life today.
But let's say that UCA fails, that we find a branch of life that is unrelated to all other branches of life. That wouldn't cause us to "reconsider our origins" in any significant way. It would a fascinating discovery, but also a kind of shrug, as in, "Oh, life originated more than once - figures." In fact, it would make sense that on the early planet life began and failed multiple times before finally persisting, and that life originated and persisted more than once is not a terribly novel thought.
If there were multiple occurrences of the "first life" then just as early humans apparently outcompeted and drove extinct all other hominid species, it is likely that some "first life" was more competitive than other "first life" and drove it extinct, explaining why we have so far detected only one UCA.
By "reconsider our origins" did you mean we should consider religious explanations? No scientific puzzle has ever resolved to a religious answer, so why would the origin of life be the first? You don't think other scientific puzzles should consider religious answers, do you, such as unifying quantum theory (the theory of the very small) and relativity (the theory of the very large)?
We have branches of species with larvae gradually changing into their adult form, and branches of species where larvae/caterpillars that completely rid of their larvae form to grow their adult appearance. So I would expect to find many species in between, or at least some branches originating from these intermediate species.
The term "intermediate species" can be misleading because it implies a species is in a transitional state from one species to another. The reality is that no species is fixed or permanent. They're all transitional. We drive stakes in the ground that we call species. Any life currently alive we call a species, and any fossil type that is plentiful in the fossil record we also tend to call a species, but those fixed points that we choose occur on long lines of change, and picking any particular point on that line and calling it a species is arbitrary. Every point on that line represents a fully formed species that is also in a state of change. There is no species in the history of life that remained the same species forever. It gradually evolved and changed or went extinct. Change is impossible to prevent, for even if the environmental pressures remained static there would still be drift since almost every reproductive event includes mutations.
--Percy

This message is a reply to:
 Message 489 by sensei, posted 06-02-2023 4:11 AM sensei has replied

Replies to this message:
 Message 492 by sensei, posted 06-02-2023 3:37 PM Percy has replied

  
Percy
Member
Posts: 22668
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.5


(3)
Message 494 of 507 (911030)
06-02-2023 9:10 PM
Reply to: Message 492 by sensei
06-02-2023 3:37 PM


sensei writes:
Well, every ancestor of a common ancestor is still a common ancestor. So the first biological cell should be a UCA. Or there had been multiple events where a biological cell formed.
I apologize that we were confusing. Granny Magda shortened LUCA to UCA, I don't know why. We're actually talking about the Last Universal Common Ancestor, also known as the Most Recent Common Ancestor. dwise1 introduced the proper term, LUCA, prior to that back in Message 475.
Now consider this: the mutation rate in unicellular eukaryotes (and bacteria) is roughly 0.003 mutations per genome per cell generation. So any living unicell would produce around 300 exact clones on average before producing one mutated cell.
Those are reasonable numbers, but what's more important is the number of mutations per generation in a population. So with a population size of 1 there would be only 0.003 mutations per generation, but with a population size of a trillion there would be 3 billion mutations per generation.
Is a trillion a reasonable size for a bacteria population, say a staph infection? If one bacterium weighs 10-12 grams, then a trillion of them weighs one gram. Did you know that that only 10% of our bodies are human cells? The other 90% of cells are bacteria (bacteria are much smaller than human cells and represent a small percentage of our total weight or volume).
The average human being carries more than a quadrillion bacteria (closer to a hundred quadrillion, but let's use the smaller figure to make it more difficult for me to make my case). If we use a very slow bacterial replication rate of one generation per hour then 3 billion mutated bacteria are created in your body every hour, or 72 billion per day. Is that enough mutations for you? In just your body alone? And with 8 billion people in the world that's 5.8 × 1020 bacterial mutations per day just within human bodies alone.
And humans are only a tiny percentage of the total biomass of the earth, so there's all the bacteria in all the other animals, then there's all the bacteria in plants, and then there's all the bacteria that live outside other life. I won't even try to guess how many bacteria that there are in the world, but safe to say that an astoundingly huge number of newly mutated bacteria appear every day.
An example of an effectively evolving bacteria is the tuberculosis bacteria. There are quadrillions and quadrillions of them throughout the world creating enormous numbers of mutations, usually SNP's, that occasionally have better success in certain kinds of environments, such as in the presence of tuberculosis drugs. There are now some strains of tuberculosis that are resistant to all currently available drugs. And this despite just 0.003 mutations per generation, or probably less since the mutation rate of the tuberculosis bacteria is low for bacteria.
Multicellular organisms tend to have much larger genomes than bacteria, and they produce many more mutations per reproductive event. For instance it is estimated that the average human baby has around 75 mutations (you'll see different estimates cited - when I look this up I typically find numbers ranging from 40 to 100). Of course our generation time is very long, so we evolve much more slowly than bacteria.
Unicells capable of surviving and successfully multiplying, would leave many offspring around, unaltered and unchanged, populating the whole globe. What's stopping them?
Unicellular life does age, but many bacteria are effectively immortal except that they have to compete for resources just like all life. For example, ask yourself what happens to gut bacteria when the host animal dies? The environment where they formerly flourished is gone and they eventually die. Or what happens when the small pool of water that was the bacteria's home dries up. They die.
We should be able to find many unicell species from the beginning, that are plausible ancestors of plants as well as animals and fungi and insects, with indications that they are clones of the same UCA cell.
But guess what. We find nothing of such type! UCA fails for sure.
I think it very unlikely that any LUCA clones could have survived until today. Even if at one time the ancient earth held quadrillions and quintillions and sextillions of LUCA clones, environmental conditions have changed dramatically since then and would be unlikely to favor the survival of that life. But why do you think the presence or absence of LUCA clones today support your position? Certainly if we found some (I don't know how we'd know we had one even if it were sitting under our microscope) it would be an astounding discovery but not particularly germane to the argument you're trying to make.
Even if mutation rates where 10 times higher in earlier days. Cells would still procuce 30 times more exact clones than mutated ones. The exact clones would always remain in majority, if all cells keep multiplying. No extinction event would wipe out the whole globe to rid it from all of the unicell species of the first era.
Any mutations that happened to be beneficial, which some mutations will be, would provide a survival advantage for their cells, enabling them to outcompete other cells, eventually replacing them. We actually witnessed this process of beneficial mutations outcompeting the unmutated versions with the covid virus. Delta outcompeted and replaced the original virus, omicron outcompeted and replaced delta, and BA.1 and BA.2 outcompeted and replaced omicron, and there have been subsequent ones that replaced BA.1 and BA.2.
So again, looking at data objectively, UCA is not very plausible.
Again, I think we should be using the term LUCA. Given the information I've provided, what do you think now?
--Percy

This message is a reply to:
 Message 492 by sensei, posted 06-02-2023 3:37 PM sensei has not replied

  
Percy
Member
Posts: 22668
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.5


(2)
Message 501 of 507 (911063)
06-07-2023 9:29 AM
Reply to: Message 497 by sensei
06-07-2023 4:06 AM


sensei writes:
As I told him before personal incredulity is no basis for a scientific argument.
You should remain silent, as you have nothing to contribute.
It's always nice to have a little irony in the morning.
I apologize that we were confusing. Granny Magda shortened LUCA to UCA, I don't know why. We're actually talking about the Last Universal Common Ancestor, also known as the Most Recent Common Ancestor.
No, we are talking about any UCA. Why does it need to be the last?
It can be UCA if you like, but you seem to be confusing it with first life, e.g.:
Your argument assumes the availability of unlimited resources, and the absence of environmental hazards that might have driven the UCA to extinction.
First cells must have lived off of non-living material, don't you think? As being the first life, it had nothing else to feed on.
Perhaps "There's not enough information to know the answer" might be a better response. One possibility is that life arose in an environment rich in organic molecules that would serve as food, so while the "non-living" appellation might be deserved, it isn't inorganic detritus.
But you had claimed that the first life would populate the entire globe and ignored that there were constantly changing conditions and environments and hazards and competition. This is what PaulK pointed out to you in Message 493 and that you quoted here, but your response didn't address the objection.
Is that enough mutations for you?
I was clearly talking about the ratio between unaltered and mutated. Your point about absolute numbers does not really address my point.
It actually does address your point, which was that the mutation rate is too slow to produce beneficial mutations. But when trillions and quadrillions and sextillions of cells are involved the number of mutated cells with potentially beneficial mutations is enormous, enabling them to outcompete the original populations. You can't pretend the covid virus mutations didn't replace previous less competitive versions of the virus in short order, mere months, because such huge numbers of viruses were involved. Something similar was true of cellular life on the ancient earth, except that the timeframes were enormous.
I think it very unlikely that any LUCA clones could have survived until today.
Hard to say, as we can only hypothesize what LUCA was like.
We know LUCA was adopted to conditions present on the earth at that time, and those conditions do not resemble the current earth at all. Conditions today are unlikely in the extreme to be hospitable to very ancient life. One big difference is that the ancient earth had an atmosphere consisting of gases like methane, sulphur dioxide and carbon dioxide. There was very little oxygen. Oceans were very different in composition, too.
Though I find it peculiar that the whole top part of the tree above fungi, insects, animals, etcetera, vanished without trace.
Either I don't understand you or you've got the tree of life analogy backwards. The most ancient life is down by the roots. The most modern life is out by the ends of branches. The top part of the tree is today. The roots are where UCA and LUCA are.
The fate of most life is extinction, some with a trace, but most with no trace. What you're claiming to find peculiar is normal.
We see many groups of species being able to survive relatively unaltered for hundreds of millions of years, around 1/10th or 1/20th of time since first life began. Crocodiles, snakes, spiders, mosquitos, all existed in roughly the same form few hundred million years ago.
Extremely few species or genuses have survived unchanged for hundreds of millions of years that we know of. You are right that species and genuses of creatures that looked much like modern mosquitos and spiders existed long ago, they just weren't the same ones that exist today. Snakes have only been around for about 130 million years, but I guess if you're not too picky anything that is long and tubular and slithers on the ground is just a snake. And about crocodiles, did you know that there used to be hundreds of species of crocodiles but that today there are only 24?
Very, very few species have existed unchanged for hundreds of millions of years. As inevitable genetic change takes place over the generations, only ecological niches that exert the same or very similar environmental pressures can keep species molded into something very similar to what existed long ago, meaning they appear to have experienced little morphological change even though there's been a great deal of genetic change. Horseshoe crabs are one of the few exceptions, one species thought to have existed for hundreds of millions of years. But like I said, it's an exception. It doesn't have much company.
So what happened to the whole branch leading up to the latest common ancestor of all mammals? The whole lineage of gradual changes, from cold-blooded to warm-blooded, from egg hatching to placental birth, from horizontal spine movement to vertical (and those are just the obvious changes), and side branches, all vanished without trace again?
Fossilization is extraordinarily rare in most environments, and some things even more rarely fossilize, such as anything small or soft.
So much, that we can only guess and hypothesize about the order in which all these changes gradually happened. And why so many drastic changes happened to be all occurring in the same lineage, does not really fit the "random" mutation narrative.
Evolutionary change is a response to environmental pressures. Species in a very stable environment will only experience genetic drift, while those in rapidly changing environments could experience either rapid evolutionary change or extinction. What we see in nature is evolution everywhere, with every species population running mutational experiments up the flagpole to see how they fly.
You seem to be asking why don't we see the same types and rates of evolutionary change everywhere. That's like asking why the weather isn't the same everywhere.
Same as we see how so many beneficial mutations just happen to be in the lineage of the single primate group with fused chromosomes. Not very likely, under the model that any drastic mutation could happen in any of the many primate groups.
No one thinks any particular line is experiencing more beneficial mutations than any others, and what's beneficial is relative. Thicker fleece in the north is a real boon, but in the south not so much.
What does happen is that a population that experiences a mutation that produces better adaptation, which means improved differential reproductive success, will be better able to compete and will likely produce more offspring, the ultimate determinate of success.
And the first primate with fused chromosomes left no unaltered descendents or descendents with only minor alterations, still showing most resemblance to the primate group before fusion, more than to human appearance today.
I don't know why you're saying this. There's no indication that the human lineage experienced a different mutation rate than other related species going back to the chromosome fusion.
Common ancestry fails on every level, to match with observable data.
Common ancestry is the only way life has ever been observed to come into this world, going back thousands and thousands of years with no reason to think it has ever been any different. What evidence are you looking at that indicates to you that at some time in the past life didn't descend from previous life?
If you want to topple common descent, you'll have to provide an observation that completely falsifies it.
No, for discussing how likely or how plausible common descent is, we can just look at all observations, objectively.
Well, yes, exactly. What observations call common descent into question?
That's the problem with theory of common descent. It's basically a reasonable narrative, full of hypotheses of how things came to be.
That's like saying "We need air to breath" is a reasonable narrative.
It may somewhat explain just the changes in adult form by random mutation, but it poorly explains the exact timing of cells, to initiate complete transformation in perfect unison, orchestrated in all the details of every transformed body part.
Nothing is orchestrated in evolution. Mutations aren't ordered up as needed. They occur randomly. If they're bad, which they usually are, then they do not fare well. If they're good then they do fare well. If they're neutral then genetic drift governs what happens to them. That's all.
The argument you're trying to make is clear. You're saying that the variety of tempo and pace in evolution indicates that it doesn't explain our observations, but you can't produce any observations inconsistent with it. And you're expressing doubt about common descent but cannot come up with a single example of life that isn't a result of common descent.
--Percy

This message is a reply to:
 Message 497 by sensei, posted 06-07-2023 4:06 AM sensei has not replied

  
Percy
Member
Posts: 22668
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.5


Message 503 of 507 (911090)
06-09-2023 6:41 AM
Reply to: Message 497 by sensei
06-07-2023 4:06 AM


I'm replying again because I think my first answer to this was incomplete:
sensei writes:
And the first primate with fused chromosomes left no unaltered descendants or descendants with only minor alterations, still showing most resemblance to the primate group before fusion, more than to human appearance today.
‚Äč
First, bisexual life never leaves behind "unaltered descendants." The mixing of sexual chromosomes guarantees that can't happen.
Second, after the fused chromosome mutation both descendant species, the one that hadn't experienced the chromosome fusion and the one that had, continued experiencing mutations and evolving at the same rate as previously. The unmutated species did not cease experiencing mutations or experience them at a slower rate. The mutated species did not begin experiencing mutations at an increased rate. Both descendant species continued to experience mutations at roughly the same rate as previously.
The chromosome-fused species that eventually became us did not much resemble us when the fusion occurred. And the species that did not experience that fusion did not much resemble whatever it eventually became, assuming it didn't become extinct.
Third, of course when the chromosome fusion mutation event was in the recent past that species still greatly resembled its parent species. Other factors being equal, a mere hundred thousand years of evolution will produce far less change than millions.
--Percy

This message is a reply to:
 Message 497 by sensei, posted 06-07-2023 4:06 AM sensei has not replied

  
Percy
Member
Posts: 22668
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.5


(2)
Message 507 of 507 (911138)
06-11-2023 9:47 PM
Reply to: Message 504 by sensei
06-11-2023 1:59 PM


Here's another request that when you reply to more than one message at the same time that you make clear which one you're replying to.
sensei writes:
You have not addressed the issue of environmental hazards.
Do you have any concrete evidence of environmental hazards that happened to kill off all UCA and all closely related UCA species, globally?
A better question is why you think this is a reasonable question to ask. There are many species that have gone extinct in just the last 10,000 years for which we know no specific cause. We presume their circumstances changed. Why do you think we should know what caused the UCA extinction event billions of years ago?
All of these methods point to the same conclusions.
That is cute, but UCA is still far from logical and plausible, if one really bothers to look at data and test hypotheses, instead of sheepishly conforming to mainstream narrative.
This is your opportunity to describe how you looked at the data and tested the hypotheses, and what your findings were.
But your objection is formed from a religious belief, not scientific evidence.
What part of the data or arguments that I posted, is religious?
Intelligent design was found to be a transparently religious repackaging of creationism in Kitzmiller v. Dover Area School District in 2005.
You still have not made any rational scientific argument. You are still stuck at personal incredulity.
You are ignored, as you make false claims about me. Or you are just not capable of doing anything but repeating some of same the evolutionist handbook arguments, no matter how irrelevant. Typical evolutionist fool!
It is my hope to remain a participant and not have to shift back to a moderator role.
It can be UCA if you like, but you seem to be confusing it with first life
You think first life was not an ancestor of todays life? Or only ancestor of some of todays life? Tell me, where is my confusion?
If life arose only once as a single cell then UCA and the first life are the same thing, but the "one cell once" hypothesis is considered unlikely. There are other more likely possibilities, such as that life arose gradually as one or more populations of self-replicating molecules (possibly RNA) that gradually became increasingly complex.
You can't pretend the covid virus mutations didn't replace previous less competitive versions of the virus in short order, mere months
You do know, that a virus is not even biologically considered to be alive, do you? It's not even a cell. And it's a parasite that needs hosts for survival.
You were wondering how mutation could cause the original unmutated variants to be replaced, so I provided covid as an example of exactly that, of mutation producing improvements that allow one variant to outcompete and replace other variants. The principle for bacteria is precisely the same, for which I provided the example of tuberculosis evolving drug resistance.
The most ancient life is down by the roots. The most modern life is out by the ends of branches. The top part of the tree is today.
Trees can be drawn with either side up or down or left or right.
The important concept is branching with the flow of time being upward.
And you're expressing doubt about common descent but cannot come up with a single example of life that isn't a result of common descent.
Examples are plenty. You just refuse to accept them, and twist the data to fit into your ad hoc narratives. And then you evolutionists claim that common ancestry of life is a fact, while it's highly dubious at best.
If you present your examples of life that didn't come from previous life then we can assess them.
Look at all the life systems that are present in todays species, for nervous system, oxygen distribution, food digestion, reproduction system, etc, also present in species of hundreds of millions of years ago. There is no sign of gradual improvement. All systems were fully present from start, in single celled species as well as in microfauna, up to all larger animals.
In very broad terms, as we trace life back in time through the fossil record we find that warm bloodedness disappears, then air breathing disappears, then vertebrae disappear, then multicellular life disappears, the signs of life itself disappears.
The huge variety of all life systems is evidence for intelligent origin. If it all came from random mutation, we would find most life systems to share some similar ancestral template, not fine tuned to the exact needs of every single species alive, from the very start.
The early naturalists found that species were exceptionally well adapted to their environments, and the theory of evolution was developed to explain that exquisitely fine-tuned adaptation. In effect life is constantly carrying out mutational experiments in real world situations, and those mutations that improve adaptation carry forward to the next generation.
--Percy

This message is a reply to:
 Message 504 by sensei, posted 06-11-2023 1:59 PM sensei has not replied

  
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