The ID Book 'Heretic:' A Brave Journey where No Man Has Gone Before


#73

I don’t know how you could calculate any probabilities when they also make this statement:

“The origin of the mitochondrion was a singular event , and we may never know with certainty the early mechanisms involved in its establishment , nor the order of prior or subsequent events in the establishment of other eukaryotic cellular features.”

If you don’t know the pathways or mechanisms, how can you determine if this was a low probability or high probability event?

What paradox would that be?


#74

You don’t seem to have a grasp on how probability works. If you shuffle a deck of cards really well and lay out the cards one by one, the order of those cards is unique in the whole history of the universe, and that exact order will probably never occur again . . . and yet it happened. In fact, every time you shuffle a deck of cards you produce a highly, highly improbable order of cards, and yet it is easy to do. Every moment of every day is marked by nearly infinite number of events that are one-off events, and yet we are able to get through our day without any problems.

What you seem to be stumbling on is called the Texas Sharpshooter fallacy. This is where you shoot a gun at a distant barn and then draw a bulls eye around the bullet hole. The probability of something happening after it happens is 1 in 1, because it happened. The evolution of the early eukaryotes could have gone in a nearly infinite number of directions, but it would have gone in one of those directions.


#75

It is completely certain because it happened. Again, you are using the Texas Sharpshooter fallacy. There are nearly an infinite number of evolutionary pathways that early eukaryotes could have taken, and the odds of them taking one of those is nearly unavoidable even though each individual pathway is highly improbable.


(Mervin Bitikofer) #76

It seems to me a good point that needs answer. It also seems to me that the debate here could be characterized as Dr. Nelson claiming that “the bull’s eye” seems to be “pre-specifiable” and that there are very few bull’s eyes (if indeed more than one). While you, @T_aquaticus, respond that there are probably (in fact must be?) infinite numbers of bull’s eyes enabling the arrow to inevitably hit one of them.


#77

To use another analogy, each of our own existences is so improbable as to be impossible. Our genomes required two people out of billions, and even then it required a specific sperm out of billions and a specific egg out of hundreds of thousands to meet each other at just the right time. And that is just for each of us. The same improbability had to occur for each of the parents, and each of their parents, and so on.

Of course, given the human proclivity towards having children there would have been children no matter what. If we rewound the clock of history and restarted it, we would probably see different people as a result, and each of their existences would be just as improbable as ours.


(Mervin Bitikofer) #78

I fully understand the concept of probability (and the sharpshooter fallacy). I’m not disputing any of that. But what I think is being suggested (I trust you will correct me @paulnelson58 if I misrepresent you here) is that there were not infinite possibilities for target locations so that a random arrow must inevitably land on one of them. He seems to be insisting that these “one-offs” can be demonstrated to be pre-specified targets (before any arrow has landed). So, to continue with your people analogy; he seems to insist it is like making up a photograph and all the details of a fictitious person ahead of time, and then gambling that the exact person made up will be born next year and live out the exact predicted life.

So it seems to me the dispute isn’t so much about probability, which I’m sure Dr. Nelson understands as it is you convincing him that there were multitudes of possible pathways that these “singular events” could have successfully taken. Your insistence that there must have been … because we are all here after all … doesn’t address his challenge. Because the question before us (as I see it) is: is life’s existence highly contingent on a knife’s edge event? Or is it a near inevitability with existing processes carrying on as they do?

[edited]


(Matthew Pevarnik) #79

A separate question, but this seems like an interesting paper that seems like a review paper of sorts:

Also, I don’t see how anyone calculates the probability of any of this without absolute knowledge of conditions 3.5+ billion years ago and absolute knowledge of all the possible mechanisms that occur at the microscopic level and even with all of that… it seems quite odd to put a limit on what probability is ‘too small’ other than exactly zero.


(Paul Nelson) #80

The questions put to me about probability estimates for the origin of the mitochondrion via endosymbiosis are misdirected. I am observing how evolutionary inferences to unique (singular) events are made, and the consequences of those inferences for phylogenetic reasoning.

Lynch, Martin, and many other investigators claim to know that an event (i.e., the incorporation of an alphaproteobacterium within an unknown prokaryotic host) happened only once in Earth history. Ask them, not me, how they know this.


#81

I don’t see how anyone could say that mitochondria were pre-specified since there aren’t any scientific papers from 4 billion years ago predicting their emergence.

That depends on how you couch that question. Are we talking about abiogenesis? If so, I don’t even know how to approach that question since we really don’t know much about possible pathways for abiogenesis. If we are talking about biological history and the pathways that led to modern species, then I would say that the species we see were highly contingent on “knife’s edge” events. It is the same argument that I made for the current human population and the makeup of each of our genomes. One very small difference early in the process of evolution could have completely changed the path of evolution and we would have very different species today if that happened. For all we know, there could have been pathways that led to a much more intelligent species than humans that would have evolved tens of millions of years ago. The current mix of species is anything but a certainty.

However, once life started and moved into enough environments it was inevitable that something would evolve. That is where the Sharpshooter fallacy enters the fray.


#82

If it is unlikely that an event would happen twice then it is usually seen as a result of common ancestry. However, lateral genetic transfer, or lateral symbiont transfer in this case, can mimic common ancestry so it must be taken into consideration in situations where it could occur.


(Matthew Pevarnik) #83

What exactly is your alternative hypothesis or explanation? That since it is difficult to answer if there was one origin of life or many or one incorporation of an alphaprotobacterium or it occurred several times, etc… therefore a better explanation is the Intelligent Designer just popped each of these into various organisms at different points in the past four billion years? Now I know you haven’t mentioned such, but I’m curious what your take is on all of this?


(Edward T Babinski) #84

And science has demonstrated time and again that “unresolved messes” can never be resolved by continuing to study natural connections and processes. That’s why we will never be able to predict what will happen when two chemicals are mixed together, and why we don’t know how the sun miraculously continues to burn in the sky or why new stars will never continue to form because they could only have been designed once, supernaturally, early in creation when an Intelligent Designer designed the stars and set them in the heavens, and why we can’t predict the weather at all, because the Designer designed and continues to move the clouds, and sends rain or drought, and why it is totally futile to study pestilence and disease to find means of prevention and cure because a Designer decrees them. In short, science is not in the business of resolving messes. We must give up on our hubris. Indeed the sons of man have only been given the earth but the heavens are the Designer’s.

I employed sarcasm above. My point is that curious scientists continue to search for connections in nature, how things are related to one another, not how they are discontinuous from one another as I.D.ists seem eager to conclude rather impatiently. Most scientists are not impatient when it comes to continuing to asking questions concerning how things in nature are connected to one another, how they all fit together. Questions like…

1 How does something in the biological world work? How does it currently function. That’s merely the beginning of examining questions pertaining to relationships in nature.

2 What are all the known analogues in the biological world that resemble how that one thing works?

3 What are a few hypothetical natural changes/alterations this one thing or its earliest ancestor might have undergone?

4 Also, how many possible paths to genetic, behavioral and morphological changes are there? Only after knowing that can we begin to whittle down the most probable natural changes/alterations this one thing or its earliest ancestors might have undergone.

It takes a lot of patience and analysis in other words, to discover how things in nature are connected. But we have discovered plenty of connections throughout nature. That is why physics, astrophysics, chemistry, biology, meteorology, embryology, neurology and cognitive science came to exist.

I.D.ists like Nelson and Behe simply regurgitate in their books the very first question above, listing what scientists have discovered about how something in nature works (like the flagellum) and continue to harp on how it all fits together. Yes it does. But did it always fit together exactly like that over the billions of years in the past when the earth was filled with nothing but single–celled life forms? The flagellum most probably arose at a time when bacteria were exchanging DNA actively–and also absorbing any DNA they came across passively–for probably over a billion years. To trace all possible changes in the DNA of such ancient bacteria over that length of time is impossible at present. There are nearly no fossils of ancient bacteria, nothing like the fossils we possess of the bones of ancient vertebrates and how their modes of transportation changed over time, i.e., from fins to limbs among vertebrates. Nor do fossils of ancient bacteria reveal their inner cellular structure. So there’s much information we are missing. And many questions remain concerning what happened during the billion years when the earth was filled with only single–celled organisms.


(Edward T Babinski) #85

Maybe start with something simpler, like how evolutionary inferences are made at all. It appears they are made via parallel trees of life produced by studying fossil succession of organisms over time, and, comparative anatomy and comparative physiology of living cousins of ancient organisms, and, a third tree of life based on comparative genomics of living cousins of ancient organisms. All three trees of life overlap to a far greater degree than if say, “flood geology” was true rather than evolution.

Even The Sequence of Fossils in the Pre-Cambrian Appears Evolution-Like

Before 700 million years ago, maybe well before: Single–celled eukaryotes arose (acritarchs), which are not to be confused with the smaller simpler prokayotes (bacteria) for which we have some very rare and very early fossil evidence.

Earlier Ediacaran: Multicellular animal eukaryotes, but these are simple, SPONGE–grade organisms (Sponges consist of communities of single–celled eukaryotes, and a sponge run through a sieve that disconnects all of its cells can re–assemble into a sponge again).

Later Ediacaran: Multicellular animal eukaryotes with more complexity than sponges, i.e. cnidarian–grade organisms.

Very late Ediacaran: Simple SLUG–grade and WORM–grade organisms (at least their tracks and burrows) – these organisms only left behind surface tracks, implying they lacked burrowing ability. Making tracks suggests that the organisms have at least a front end and a back end, a mouth, anus, and gut connecting them. These are almost certainly bilaterians.

Very late Ediacaran: The very first biomineralized “skeletons”, e.g. Cloudina, basically a WORM secreting a tube, as well as the first evidence of predatory boring. Cloudina gets no mention at all in Meyerʼs book on the Cambrian.

At the beginning of the Cambrian, we start to see more complex burrowing – e.g., vertical burrowing through sediment, clearly indicating WORM–grade organization and an internal fluid skeleton, i.e. a coelom. The burrows gradually increase in complexity over 10 million years.

We also see SMALL SHELLY fauna: The fossilized shelly parts start very small and very simple, gradually diversify, growing more complex, radiating especially in the Tommotian. By the end of the Tommotion, some of the “small shellies” can be identified as parts of larger, “classic” Cambrian animals. The Tommotian is an utterly key period for any serious discussion of the Cambrian explosion. Unfortunately, the word “Tommotian”, or any equivalent terminology does not even appear in Meyers’ book! The Small Shelly Fauna (SSF) gets just one (one!) mention in the book, buried in endnote 27 of Chapter 4.)

All of the above evolution-like stages of increasing complexity preceded the Cambrian “explosion.”

In the Cambrian itself one can’t help but note how worm-like the Chordate representative was (the earliest representative of the same phylum as us). The earliest representatives of the phylum Chordata resembled filter–feeding worms that happened to swim. They didnʼt have jaws, scales, a bony skeleton, or anything else that most readers would even associate with a “fish!” And the process of their development from the Cambrian onward, before they even evolved jaws, included nothing but rounded sucking mouths.


(Jon Garvey) #86

Hmm - I’m not sure that Paul has the weakest grasp on probability theory in this discussion.

You shuffle a card pack, and what is the probability for the sequence dealt? That depends partly on how many cards, which dictates the possible number of combinations and, yes, because that is 52 factorial, it comes out as around 8X10^67, which rivals the number of particles in the universe in some estimates.

But that only translates into a probability as it is used to measure our ignorance of the actual causes involved. There is no absolute probability in existence at all, and no practical probability without knowing some of the specific conditions. In this case we know a lot more than you’d think - that there are 52 cards which, when turned over, will each be different. That gives us a basis to calculate the total of combinations possible, ie that 8X10^67. But we’re not there yet.

Our shuffling involved a set of movements which determined exactly which sequence will appear once we turn the cards over, and given high speed photography and a knowledge of the original order, that sequence would be knowable. So the probability for the machine operator to predict the outcome is 1. But the shuffler, if he played fair, has only an 1:8X10^67 chance of predicting the outcome.

So which probability is “right”? Answer: the question is meaningless, being entirely one of knowledge or ignorance of prior causes - the actual order is fixed from the moment you stop shuffling. If you sneakily saw the first cause, the probability will increase to 1:51 factorial.

And of course, if you were a card sharp and chose the sequence, the probability for you is 1, but for me, even if I know you did it, still 8X10^67.

Conclusion: there are no absolute “probabilities” in the real world, but only events about which, when we know only some of the causes, we can measure our ignorance of the rest by a probability. If we know none of the causes, no probability exists, any more than you can measure the logic of an unspoken sentence. It’s not that we can’t calculate the probability - there just isn’t one there to measure.

So what of an event that is said to be a one-off (I’m British, you see!) - let us say the origin of life. How unlikely is that? Since we cannot replicate the causes of that event (and are actually ignorant of them), we don’t even know the “number of cards”, so are in no position to talk about “probability” at all.

If we imagine life must hinge on some individual chemical reaction, I suppose we could do some kind of estimate of the total possible number of chemical reactions, maybe. But it would be as meaningless as Drake’s equation, because our “chemical theory” is something we made up, not real knowledge of what began life. We don’t even have a secure handle on what constitutes life. Our probability calculation is, essentially, a fairy tale… though if our chemical theory happened to be correct, to an omniscient God, the probability of that combination occurring would be 1, just like the guy with the high-speed camera watching you shuffle.

Presumably a non-omniscient god would at least know the requirements for life, and so have enough information to do a probability calculation. But who wants to believe in a god with a calculator?

If, instead of waiting for chemistry, God deliberately made the first cell on his celestial workbench, to him the probability would be 1, and our probability would be 1 if we believe God did that, or 0 if we don’t. That’s because he stacked the deck which, in this case, only has one card, called “origin of life”.

As far as I can see, there is no science to be done on such a singular contingency, beyond recording that life exists, so it started somehow. And you don’t need a degree to conclude that. But we can be a little sciency if we have concluded it did, indeed, only happen once.

First we can be pretty sure we’ll never find the cause, since if it hasn’t happened again in 4.5 billion years it must involve absolutely unique circumstances we won’t even guess how to reproduce.

We can also say, with some certainty, that there are not a multitude of possible ways for life to form, of which the one that occurred just happened to be the one dealt by nature. If that were so, “life forming events” would be a class containing many examples we would have discovered, and then we could start doing some kind of scientific probability calculation, having more than one point to work on.

(To argue that the existence of life shut the door to all further such events is another mere assertion for which we cannot even attribute a probability).

Lastly, we can say that we have no natural information about the event that would enable us to say whether it belongs to the category of “fortuitous” and “natural”, or “supernatural.” However, calling it “natural” would be meaningless if it is genuinely fortuitous, as far as doing “systematic science” is concerned. One point and the origin is not a good basis for ascertaining knowledge of cause.


(Dennis Venema) #87

Jon, you’ve got some very good thoughts here. Forgive me for one quibble on this quoted point. It’s very likely that even if life had originated more than once in the last few billion years that the previously existing life would simply outcompete the later arrivals. Once life got started it likely spread pretty quickly. Any complex macromolecules around would probably be utilized. So, living things greatly reduce the probability of a second abiogenesis event. That’s not to say it’s impossible to have two or more - and scientists are open to that idea and have looked for evidence for a second one - but thus far the evidence we have supports only one event.


(Mark D.) #88

I agree. Unless there are places left on earth containing the necessary conditions for life to start where there is absolutely no already existing life forms, it is highly unlikely that new arrivals have a snowball’s chance in a hot place. The very first single cell forms of life would have been very simple, merely find food and avoiding toxins while replicating asexually. Eventually some cells developed the ability to consume other simple creatures. Only then would the ability to sense other life forms and determine which are threats (or possibly food) become something that could be selected for.

So any life forms emerging in the simplest state of merely metabolizing would become the easiest of meals for life forms that had already undergone some selective pressures.


(Jon Garvey) #89

Yes Dennis

To be honest the nuance I wanted to look at most was the idea that there might be many different routes to the same goal, which would make “one event” even more surprising than it is. But mostly I was taking the thread’s existing theme of “unique events” and running with it.

OTOH such complex molecules would also be one less hurdle for a new biogenesis event to overcome: a whole lot easier to transform complex molecules than start from scratch with simple ones, one would think. After that it might well be the kind of pic’n’mix Carl Woese seemed to favour.

How far we’ve come from spontaneous generation on tap - life always comes from life, except once.


(Dennis Venema) #90

It’s certainly possible - and there is some evidence that some viruses might predate the last universal common ancestor (LUCA). I cover some of that when I teach virology. What defines “life” gets blurry back then too.


(Paul Nelson) #91

Well, there’s the rub. I have to present a poster at a meeting today (ISCB / ISMB 2018 in Chicago), so am rushed, but wanted to call attention to this very insightful paper by the Israeli philosopher of science Iris Fry:


(system) #92

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