Are All UFO Reports Wrong, Or Are They Evidence That UFOs Exist?

[John J.]

The gene that controls bicolor distribution can be mutated by, say, ultraviolet radiation, in an infinite or limited variety of ways most of which are unfavourable to bicolor distribution and wouldn't result in an adaptive/surviving population. That a gene for bicolor distribution has evolved is highly improbable without such evolutionary bias towards complexity.

There are many diverse species which have the word "bicolor" in their formal nomenclature, but I'm guessing you're not referring to one of those.
Maybe it's a specialised biological term that I wouldn't have come across-
-could you explain what you mean by "bicolor distribution", or give me a suitable link please, LilWabbit?
(Genuine query; sorry if it's a bit dumb).

The simple point is that the rate and nature of favourable (increasingly complex) mutations that has occurred in our biosphere hasn't been mathematically accounted for on a premise restricted to, and accurately reflecting, the foregoing two processes without a (3) third factor of some sort of bias towards complexity

If we haven't got a robust, testable mathematical model of evolution/ speciation it doesn't mean that there is a fundamental problem with evolutionary theory. It certainly doesn't justify the mooting of an irresistible march toward complexity.

The implied claim (I think; apologies to LilWabbit if I've misunderstood), that there hasn't been enough time for natural selection alone to "deliver" the level of complexity that is seen, does seem rather similar to the claims made by "Intelligent Design" supporters. The conclusion (based on that extremely shaky premise), that therefore some unidentified exterior force, or inexplicable inherent bias, must have assisted life to get where it is today similarly seems (to me) to evoke "I.D."

Individual mutations (changes to the genome) are not, of course, increasingly complex- at the specie level complexity may increase over time, but that complexity is cumulative. Mutations occur, in much the same way as they always did, in organisms that might be more complex than their predecessors.

Complexity per se is not selected for.
We all accrue DNA mutations, most of which we could do without, but they all increase our complexity as organisms.
Almost certainly none of us will have our chances of reproduction enhanced by these random changes to our genotype,
and sadly most of us know, or will know, people who are killed by random genetic mutations.

We shouldn't equate "complex" with "beneficial". Most increases in complexity in an individual's DNA are deleterious.

(Edited to add) Of course, if we hadn't evolved to the level of complexity required to have this conversation, we wouldn't be wondering why the biosphere hadn't allowed it. A bit like the weak anthropic principle.

 

[LilWabbit]

There you go again, once more expressing a concept in great sweeping walls of obfuscatory language and then insulting those who disagree with or misunderstand you. We have been down this road with you before. If you think clarification is needed, perhaps it is because you did not state it clearly the first time ...or the next ...or the next. You have always been free to explain, but have chosen not to do so. Perhaps the fault lies with the writer rather than the reader.

No @Ann K. It's your tribal ideological affiliation with certain posters which clearly clouds your judgment as to who's obfuscating what and what's well-reasoned and lucid argumentation as opposed to wilful misreading just to compare as a clever interlocutor. You're not getting the dynamics right, nor are you objective and yet often position yourself as an honest broker. Disagreement is a word that would accurately describe what's occurring if there were evidence of understanding of what was carefully written. Such evidence is in very short supply here.

And no, I do not think I could have been any clearer about my main points than I already have been. If you wish to fault it on poor linguistic expression, you're fully entitled to do so. But we disagree. Feel free to demonstrate how what I intended to convey could be expressed more lucidly, succinctly and intelligibly. A pursuit of accuracy in conveying the meaning of nuanced multi-faceted concepts is the principal -- and totally natural -- reason for the relative 'difficulty' of quick comprehension and hence a more attentive, a slower and an unbiased study of the argument is required to avoid such misreadings in the future. I've tried to be as succinct as possible.

There's a reason why 200-page dissertations by Ph.Ds exist on these topics, so we're in a 'difficult comprehension' territory to begin with. It should be accepted as a given rather than constantly imposing a school teacher expectation or journalistic standards of easy-to-read overviews on fellow posters. As if two-paragraph overviews are possible for every topic and discussion for adequately conveying the salutary points intended by the author. And then subsequently judging the author for poor expression when failing to meet such an unreasonable standard. (And none of this implies my own hubris of thinking that my expression never needs to be worked on.)

P.S. Calling out a toxic style of ignorant discourse characterized by disrespect (i.e. not seriously studying a written text due to personal bias against its author) to a poster's sincere effort to convey a totally neutral point, coupled with a Dunning-Kruger effect spiced with a condescending tone, is not an insult nor impolite but an accurate observation that needs to be expressed to address the actual passive-aggressive impoliteness that constantly goes under the radar here.

 

[LilWabbit]

If we haven't got a robust, testable mathematical model of evolution/ speciation it doesn't mean that there is a fundamental problem with evolutionary theory.

If a model doesn't even closely predict an observation, we have a problem. In all branches of natural sciences. No matter how popular or trendy the model be.

In this case, it's not so much even a question of an incorrect model but an insufficient one to account for the observed rate of evolution of increasing complexity as outlined earlier. A more adequate model does not imply creationism. It could even invoke the multiverse and be decidedly atheist. That's a whole separate discussion and should not be confused with the discussion on probabilities I was solely concerned with. However, the irrational resistance to even accept the notion of an improbable evolution under current models stems from undercurrent allergies to theism that should have no bearing on a rational discussion focused on probability calculations and evidence.

Mine was a response to @Scaramanga, citing the infinity of randomly varying universes, not being wrong about the improbability of the emergence of life and increasingly complex systems in a sole universe. Especially with the Second Law of Thermodynamics being applied to it. His was the total opposite of a creationist position. But there's an overall agreement with theists on the improbability under a model that doesn't invoke multiple universes. Why should that matter on this thread? My answer: It shouldn't, but the fact that it matters to some reveals ideological rather than scientific commitments. Including those of Sean Carroll.

And @Mendel, quoting Sean Carroll's (a pop scientist and a bit of a narcissist) musings on anything complexity hardly refutes what was written about the Second Law of Thermodynamics in response to your mischaracterization of early universe as a simpler or less complex entity, and is itself a testimony to reliance on ideologically very committed 'scientists' who love to theorize more than demonstrate. Also he's using a completely different definition of complexity from the complex systems defined earlier on this thread in response to your query. The definition I provided agrees with the way evolutionary biologists such as Niles Eldredge understand complex systems, whom I will quote in a later post.

 

[markus]

The point is that our existence is that basis.

Q: What is the probability that a gambler will guess the outcome of a coin toss correctly, conditioned on the fact that he guessed it correctly the previous 50 times?

A: No matter how lucky he has been so far, the probability is still the same, because the coin tosses are independent*. In this guise, I'm sure this is a point that's familiar to everyone here. In Bayesian inference terms, this means that our existence does not in any way strengthen our confidence in the probability of life arising "not being too small". Either we observe the universe, or we don't observe anything, either we win the lottery or we aren't around to be sad that we didn't.

Spoiler: Bayes's theorem

This can be illustrated with an application of Bayes' theorem, but is not very interesting because the key step is that conditional probabilities collapse for independent events :

P(intelligent life exists elsewhere | we exist) =  P(we exist | intelligent life exists elsewhere ) P(intelligent life exists elsewhere )
                                                   --------------------------------------------------------------------------------------
                                                                                      P (we exist)
                                                                              
P(intelligent life exists elsewhere | we exist) =  P(we exist) P(intelligent life exists elsewhere )
                                                   --------------------------------------------------
                                                                      P (we exist)
                                                            
P(intelligent life exists elsewhere | we exist) =  P(intelligent life exists elsewhere )

That is, you get your prior probability back out, undisturbed.

* Now for the matter of independence. The assumption of statistical independence is often the most suspect in any statistical argument, but that question is not too important here. Why? Consider the opposite: say that there are correlations in whether life arises in different planets. There may be various causes for this, such as panspermia, as mentioned by Ann K, or some advanced civilization seeding life throughout the universe like the monolith aliens from 2001, or maybe god-did-it or similar exotic explanation. If I were claiming definitively that we are alone in the universe, I should better establish that e.g. panspermia cannot occur. But that's not what I'm saying. What I'm saying is that we just don't know how prevalent life is in the universe and that there's nothing inconsistent or suspicious about us being the only ones. To that end, it suffices merely to note that panspermia (or seeding etc) either happened (to or from Earth, the only planet known to contain life) or it didn't. Panspermia itself relies on a number of cosmic coincidences so surely it's not too unlikely that it didn't, and so it's just fine to assume independence for the purposes of this argument. If any life-carrying planet has a 50% chance of spreading life to its neighbors, but life itself only has a 1e-2000 chance of arising in any given universe-volume, that still leave us with a 50% chance of being alone. Much lower than in the no-panspermia case but definitely not negligible.

Incidentally, the question of independence is also the main difference between the subject of this conversation and the husband with the bottles of wine, since the presence of a second bottle of wine is surely correlated to the presence of a first: they were "seeded" in the shopping bag, if you will. They did not arise spontaneously and we are not witnessing the story from the point of view of the bottle!

Our situation being special is precisely the input that comes up with the value 42%, I have not overlooked that at all.

? (2-exp(1))/(1-exp(1))
0.4180

I'm sorry, I don't understand what you're calculating. Can you explain it?

 

[Scaramanga]

We know biology to be a thing though, and we are looking for it in other places than Earth. We knew birds existed in the UK was it pseudoscience to look for birds in America?

Is it the name you object to? What do you think we should call it?

Hmm, it's hard to put my finger on it precisely, but something about the over-confidence of 'Exobiology' just irks me. I mean, we've already had Bill Clinton jumping the gun, which to me represented an over-eagerness for the 'Alien microbes found' type of headline. Of course we should be looking for alien life, but setting up entire departments with 'Exobiologists'...why is that any different to setting up departments of Parapsychology based on a few Zenner card or other readings and a lot of wishful thinking ? When did science and the establishment of science jobs, titles, and university departments, stop being about actual empirical evidence ?

 

[Martinicus1]

Hmm, it's hard to put my finger on it precisely, but something about the over-confidence of 'Exobiology' just irks me. I mean, we've already had Bill Clinton jumping the gun, which to me represented an over-eagerness for the 'Alien microbes found' type of headline. Of course we should be looking for alien life, but setting up entire departments with 'Exobiologists'...why is that any different to setting up departments of Parapsychology based on a few Zenner card or other readings and a lot of wishful thinking ? When did science and the establishment of science jobs, titles, and university departments, stop being about actual empirical evidence ?

Life emerged early in earth's history, at about the same time oceans are thought to have formed, both about 4 billion years ago - evidence that life started when conditions were right. What's been the direction of travel over the last 30-40 years? We have found life in places on earth where it was thought previously impossible and are finding planets, particularly planets where conditions may also be right may be commonplace in the galaxy. There wasn't evidence for such planets pre-1990s, so should science not bothered looking, developing the tools to find out? What comes first in the scientific method, observations/questions or evidence base?

 

[LilWabbit]

Niles Eldredge, an accomplished anti-Intelligent Design evolutionary biologist and paleontologist, writes on the diversity of ways evolutionary biologists (ranging from systematists and paleontologists to geneticists of various sub-brands) define evolution. But in the same token he says none of them really disagree with the prediction of an overall evolutionary sequence from simple to complex species (bold added). Thereby Eldredge winds up demonstrating how seeing an overall evolutionary direction/trajectory/trend/sequence towards increasing complexity doesn't need to imply theism nor inevitability. And that this overall and in many ways defining trajectory underlying the very term "evolution" is evidence-based -- an observable prediction of the theory -- and not in any way a serious cause of contention amongst the majority of evolutionary biologists.

Article:

Which brings me to the most powerful connection between evolution and complexity: Today, we have a spectrum of complexity ranging from prokaryotes (Achaeans, true bacteria) up through elephants. We wonder: Which came first — the prokaryotes, or the multicellular, highly differentiated eukaryotes — i.e., bacteria or elephants? We imagine, of course, that the prokaryotes, being the simpler, must be most similar to the earliest organisms on the planet; so, assuming life began here, we predict that the oldest fossils should be prokaryotes: They are — going back over 3.5 billion years — and the only form of life on the planet for at least another 1 billion years. Then came the more complex eukaryotic micro-organisms. And so on. Elephants came way later.

Thus one grand prediction of everyone's version of evolution is that life evolved from the simple to the complex — a prediction that at one and the same time shows the notion of evolution to be thoroughly scientific — and in this instance, abundantly corroborated.

No such equivalent predictions are forthcoming from "Intelligent Design" thinking. One would probably imagine that a truly intelligent designer would simply put the best version on the scene from the get-go, and dispense with all the simpler, less complex versions — instead of the billions of years of tinkering with what genetic information was on the scene — sometimes, though not always, coming up with something more complex. But complexity is not inevitable. Think about it: Bacteria and other simple things are still running the planet.

Source: https://www.academia.edu/48252798/Casting_an_Eye_on_Complexity

 

[FatPhil]

Q: What is the probability that a gambler will guess the outcome of a coin toss correctly, conditioned on the fact that he guessed it correctly the previous 50 times?

A: No matter how lucky he has been so far, the probability is still the same, because the coin tosses are independent*.

That depends if the gambler is a robot with high speed cameras that can see the initial orientation of the coin, and the velocity and angular velocity it is launched with, and who has been programmed to calculate which orientation the coin will land. If it is, then "the probability is the same" should not hold. With each successful guess, we have more confidence in the gambler's predictive capabilities, and by the time it's reached 50 correct tosses and no failures, we should conclude that its probability of success is found in a bell curve peaking around 99%.

I'm sorry, I don't understand what you're calculating. Can you explain it?

Poisson distribution, where we have no idea about mu, but know lambda's at least 1, so just set it to 1. We can exclude the 0 outcome, and we're calculating the sum of all outcomes greater than 1. The only assumtion is that there's no reason to believe we have been specifically set up to favour a positive result here. Given everythng we do know about the universe, such as the lack of a guiding higher power, that's not just a fair assumption, it should be the default one, deviating from it would require evidence of fine tuning.

 

[FatPhil]

Niles Eldredge, an accomplished anti-Intelligent Design evolutionary biologist and paleontologist, writes on the diversity of ways evolutionary biologists (ranging from systematists and paleontologists to geneticists of various sub-brands) define evolution. But in the same token he says none of them really disagree with the prediction of an overall evolutionary sequence from simple to complex species (bold added). Thereby Eldredge winds up demonstrating how seeing an overall evolutionary direction/trajectory/trend/sequence towards increasing complexity doesn't need to imply theism nor inevitability. And that this overall and in many ways defining trajectory underlying the very term "evolution" is evidence-based -- an observable prediction of the theory -- and not in any way a serious cause of contention amongst the majority of evolutionary biologists.

Article:

Which brings me to the most powerful connection between evolution and complexity: Today, we have a spectrum of complexity ranging from prokaryotes (Achaeans, true bacteria) up through elephants. We wonder: Which came first — the prokaryotes, or the multicellular, highly differentiated eukaryotes — i.e., bacteria or elephants? We imagine, of course, that the prokaryotes, being the simpler, must be most similar to the earliest organisms on the planet; so, assuming life began here, we predict that the oldest fossils should be prokaryotes: They are — going back over 3.5 billion years — and the only form of life on the planet for at least another 1 billion years. Then came the more complex eukaryotic micro-organisms. And so on. Elephants came way later.

Thus one grand prediction of everyone's version of evolution is that life evolved from the simple to the complex — a prediction that at one and the same time shows the notion of evolution to be thoroughly scientific — and in this instance, abundantly corroborated.

No such equivalent predictions are forthcoming from "Intelligent Design" thinking. One would probably imagine that a truly intelligent designer would simply put the best version on the scene from the get-go, and dispense with all the simpler, less complex versions — instead of the billions of years of tinkering with what genetic information was on the scene — sometimes, though not always, coming up with something more complex. But complexity is not inevitable. Think about it: Bacteria and other simple things are still running the planet.

Source: https://www.academia.edu/48252798/Casting_an_Eye_on_Complexity

I don't think anyone's arguing against that point. It's an unavoidable consequence of even the simplest view of what's taking place. @Mendel's random walk from pages back will even achieve that, and that's held up as the canonical example of a lack of direction. There're simply more available complex forms in the genetic phase space, so you'll inevitably reach, or at least probe, the space of more complex forms simply from an entropic viewpoint (until you've started to exhaust new possibilities, of course, but phase space is exponential (it's beyond even that, due to the programatic nature of genes), and space-time is polynomial, there's not enough time to explore every corner).

However, I personally object to your idea that there is a "rate of complexification" for two strong reasons. Firstly, you've not provided a measure for "complexity", and you can't enumerate a rate of change of a quantity you can't measure. It can't be a measure of the genes themselves, otherwise the angiosperms would be winning the complexity race, and the last time I heard it the Pastoral Symphony was neither composed by, nor performed by grass. It seems like it's little more than a "you know it when you see it" measure. Hence the cartoonishly simplistic example of comparing a bacterium with an elephant. How about something a bit harder - which is more complex: a peacock or a penguin? In the words of your good self - show me "a credible calculation". Or alternatively drop your presupposition that such a calculation is either possible or even meaningful.

And secondly, there's absolutely no reason to believe that, even if you were to be able to enumerate it linearly, yet to be proven, there is *a* rate of at which life on earth increases complexity. Different entities in different environments at different times will have a different rate of adoption of new traits. The Michegan E. Coli experiment demonstrate this - its evolution has slowed down over the years, as you would expect. Except when it suddenly evolves the ability to eat citric acid, or whatever it was, and then its approach to a possible equilibrium was suddenly punctuated with some rapid changes. So, what's its rate - slow and getting slower, or fast? Or both? Or neither?

 

[LilWabbit]

I don't think anyone's arguing against that point.

To claim that there's no consistent direction towards complexity in an evolutionary sequence of successive emergence of incresingly complex organisms during somewhat short spurts of evolutionary activity from the first crude forms of invertebrate animal life some 600 million years ago to the genetically modern man about 50,000 years ago is arguing against the point.

This roughly 600 million year-long process is, from the geological perspective, a fairly short time-span and can be established through radioactive dating and fossil records. Under some estimates roughly a thousand species intervened between the appearance of one-celled organisms and the mature human being. In terms of a probability calculation, this shows that there was no time for anything like an "unlimited" or "open-ended" experimentation in evolution. In each case, the transition from one species to another was a process leading from a less complex (and therefore more probable) to a more complex (and thus less probable) configuration. Finally, the evidence from the fossil record consistently shows that evolution was not a smooth, gradual process. Rather, there were long periods of stasis and stability (the so-called plateaus), punctuated by much shorter periods of rapid change.

The measure for complexity used in any such calculation can be rather easily inferred from the classes of increasingly complex species identified by Eldredge. But if you want an attempt at a more formal expression, it's really not that hard. But where there's no will, there's no way.

The complexity of a biological system is determined by the net value of (1) the # of the cells of the system's neural apparatus, (2) the # of the levels of hierarchy of subsystems of the organism, (3) the variety in kind of the behaviour of these subsystems, and (4) the variety in kind of the observationally distinguishable behaviours of the system whereby it is capable of interacting with itself and its environment.

Using this measure one can roughly estimate whether the peacock is more complex than the penguin, or vice versa, or whether they're roughly equal in complexity. In any case, the relevant point is not in the individual species-level differences of complexity but in the broader taxonomical categories, also known as classes, that are shown in the fossil record to emerge successively and separated by plateaus, which can be more clearly differentiated in complexity using said or similar metrics of systemic complexity.

 

[Mendel]

Firstly, you've not provided a measure for "complexity", and you can't enumerate a rate of change of a quantity you can't measure. It can't be a measure of the genes themselves, otherwise the angiosperms would be winning the complexity race, and the last time I heard it the Pastoral Symphony was neither composed by, nor performed by grass.

Here's a nice graph to support that.

Article:

Genome size ranges (in base pairs) of various life forms

Source: https://en.m.wikipedia.org/wiki/Genome_size

That said, I'd probably understand complexity to refer to the phenotype, but it's also true that's hard to measure. Consider also that beehives and ant colonies are pretty complex, and have been around for a long time.

 

[LilWabbit]

That said, I'd probably understand complexity to refer to the phenotype, but it's also true that's hard to measure. Consider also that beehives and ant colonies are pretty complex, and have been around for a long time.

Ant and beehives are an excellent testimony of the complexity of the organisms known as 'ants' and 'bees'. They are remarkably complex under the metrics I just provided and which agree roughly with how biologists evaluate the complexity of organisms. And yet your regular Norwegian farmed salmon before being chopped up for sushi is more complex under the same metrics.

 

[Landru]

P.S. Calling out a toxic style of ignorant discourse characterized by disrespect (i.e. not seriously studying a written text due to personal bias against its author) to a poster's sincere effort to convey a totally neutral point, coupled with a Dunning-Kruger effect spiced with a condescending tone, is not an insult nor impolite but an accurate observation that needs to be expressed to address the actual passive-aggressive impoliteness that constantly goes under the radar here.

It is in fact an insult and impolite and will not be tolerated on Metabunk.

 

[LilWabbit]

To claim that there's no consistent direction towards complexity in an evolutionary sequence of successive emergence of incresingly complex organisms during somewhat short spurts of evolutionary activity from the first crude forms of invertebrate animal life some 600 million years ago to the genetically modern man about 50,000 years ago is arguing against the point.

This roughly 600 million year-long process is, from the geological perspective, a fairly short time-span and can be established through radioactive dating and fossil records. Under some estimates roughly a thousand species intervened between the appearance of one-celled organisms and the mature human being. In terms of a probability calculation, this shows that there was no time for anything like an "unlimited" or "open-ended" experimentation in evolution. In each case, the transition from one species to another was a process leading from a less complex (and therefore more probable) to a more complex (and thus less probable) configuration. Finally, the evidence from the fossil record consistently shows that evolution was not a smooth, gradual process. Rather, there were long periods of stasis and stability (the so-called plateaus), punctuated by much shorter periods of rapid change.

The measure for complexity used in any such calculation can be rather easily inferred from the classes of increasingly complex species identified by Eldredge. But if you want an attempt at a more formal expression, it's really not that hard. But where there's no will, there's no way.

The complexity of a biological system is determined by the net value of (1) the # of the cells of the system's neural apparatus, (2) the # of the levels of hierarchy of subsystems of the organism, (3) the variety in kind of the behaviour of these subsystems, and (4) the variety in kind of the observationally distinguishable behaviours of the system whereby it is capable of interacting with itself and its environment.

Using this measure one can roughly estimate whether the peacock is more complex than the penguin, or vice versa, or whether they're roughly equal in complexity. In any case, the relevant point is not in the individual species-level differences of complexity but in the broader taxonomical categories, also known as classes, that are shown in the fossil record to emerge successively and separated by plateaus, which can be more clearly differentiated in complexity using said or similar metrics of systemic complexity.

Summary for the sake of relevance and clarity:

There's theoretically an infinite number of ways for radiation trauma to impact genes at random variance, and by extension an infinite range of possible novel phenotypical configurations. This can be established without even considering other causes of genetic mutation such as incomplete chemical processes.

Yet there's only a finite stretch of punctuated evolutionary periods during which these mutations are thought to have occurred at a certain averaged frequency to cause more complex species. Therefore the probability for even a single organism to produce mutated offspring falling within a narrow range of more complex favourable mutations is zero, let alone for their offspring to continue mutating favourably within mutant subpopulations into more complex and therefore less probable configurations.

So either we invoke the infinite universes metatheory to preserve an open-ended random variation within our evolutionary model while factoring in our existence, or else the catalogue of possible configurations in our model must be finite (whilst still extensive) and bound to produce increased complexity given sufficient time of random experimentation within the said finite catalogue -- say -- a billion or so years.

If it's a finite catalogue and/or otherwise bound towards complexification overtime (for whatever reason), then complexification is likely in other similar planets given sufficient time. If infinite and/or unbiased, life in other planets is highly unlikely.

We don't know which one it is.

I hope the above clarifies the logic and relevance of the analysis to this discussion.

 

[FatPhil]

Summary for the sake of relevance and clarity:

Yet there's only a finite stretch of punctuated evolutionary periods during which these mutations are thought to have occurred at a certain averaged frequency to cause more complex species. Therefore the probability for even a single organism to produce mutated offspring falling within a narrow range of more complex favourable mutations is zero, let alone for their offspring to continue mutating favourably within mutant subpopulations into more complex and therefore less probable configurations.

Thank you for that clarification. You may now have my complete disagreement.

 

[LilWabbit]

Thank you for that clarification. You may now have my complete disagreement.

Thanks for the honour. Many more to come!

 

[Mendel]

The complexity of a biological system is determined by the net value of (1) the # of the cells of the system's neural apparatus, (2) the # of the levels of hierarchy of subsystems of the organism, (3) the variety in kind of the behaviour of these subsystems, and (4) the variety in kind of the observationally distinguishable behaviours of the system whereby it is capable of interacting with itself and its environment.

It's always hard for me to reply posts like these that are completely unsourced; it's never clear whether these are your personal definitions, and it's hard to use web searches to dig deeper on these.

I have a hard time figuring out how such a metric works in practice; given that whale brains are bigger than early Neanderthals are bigger than homo sapiens' brains, it's not really clear to me how the other factors would be used to offset the first one.

It kind of does explain why some people expect aliens to have big heads.

And @Mendel, quoting Sean Carroll's (a pop scientist and a bit of a narcissist) musings on anything complexity hardly refutes what was written about the Second Law of Thermodynamics in response to your mischaracterization of early universe as a simpler or less complex entity

my heart's not set on Carroll, I googled "complexity entropy" and saw a multitude of hits that argued entropy drives complexity, at least in the young universe (which was our context anyway). Your only source is yourself.
In the infancy of the universe, there weren't many subsystems, so by analogy with the complexity definition you're using there, it wasn't very complex. You keep contradicting that, but I haven't really been able to make out your counterargument. The second law of thermodynamics does not involve complexity.

It would be really nice if we had some metric by which we could relate complexity, intelligence, and the ability to develop spaceflight, because then we'd have a better idea of how much evolution is required at minimum for an alien species to be able to make contact.

 

[LilWabbit]

It's always hard for me to reply posts like these that are completely unsourced; it's never clear whether these are your personal definitions, and it's hard to use web searches to dig deeper on these.

I have a hard time figuring out how such a metric works in practice; given that whale brains are bigger than early Neanderthals are bigger than homo sapiens' brains, it's not really clear to me how the other factors would be used to offset the first one.

Hence factors 2, 3 and 4 where 4 is particularly significant in determining the distinction in favour of our otherwise smaller but more efficient brains. Don't forget whales, they have also more brain cells. Even in the neurocortex if I remember correctly.

The suggested model of complexity can be refined in many ways but it's sufficient even in its current form to provide an example of how to reasonably distinguish between the animals you suggested. It is compatible with the main taxonomical classes which is the salient point here. Not whether or not dolphins are more complex biologically than chimps or elephants -- all being complex mammals in the same overall taxonomic class.

my heart's not set on Carroll, I googled "complexity entropy" and saw a multitude of hits that argued entropy drives complexity, at least in the young universe (which was our context anyway). Your only source is yourself.
In the infancy of the universe, there weren't many subsystems

How do you know what the universe contained within in its infancy? Did Sean Carroll tell you that too?

so by analogy with the complexity definition you're using there, it wasn't very complex. You keep contradicting that, but I haven't really been able to make out your counterargument. The second law of thermodynamics does not involve complexity.

I offered explicitly a model to compare complexities of biological systems. You're taking the discussion entirely outside of the biological context. However, any claim of singularity being a simple system in terms of its component parts and behaviours whilst contrasting it to an expanded universe resulting from entropy (which does not even theoretically operate similarly to singularity as a fully integrated system) begs for evidenciary support, further theoretical clarity and reasonable criteria for comparison before even entering such a discussion. You nor Carroll provided none, and the whole argument is a digression.

Counter-arguments to your arguments will be provided as soon as you actually employ such arguments to accurately address mine. Usually you refuse to do so and hence there's no need to bother countering irrelevant excursions into unrelated speculation.

The Second Law of Thermodynamics involves entropy which directly concerns the reduction of system's properties and thereby its complexity. Even if many of the constituent elements of the system survive as far-scattered photons in the heat death of the universe, nothing else does. The system has become simpler.

 

[Scaramanga]

Life emerged early in earth's history, at about the same time oceans are thought to have formed, both about 4 billion years ago - evidence that life started when conditions were right. What's been the direction of travel over the last 30-40 years? We have found life in places on earth where it was thought previously impossible and are finding planets, particularly planets where conditions may also be right may be commonplace in the galaxy. There wasn't evidence for such planets pre-1990s, so should science not bothered looking, developing the tools to find out? What comes first in the scientific method, observations/questions or evidence base?

Well Prof. Kipping deals with the 'life arrived early' fallacy in the video I posted earlier. It is yet another of those anthropic issues, because there's only really about 500-600 million years left for complex life on Earth..so life had to arrive early for there to be 4 billion years for complex life to arise. If life had arrived 500 million years later and taken the same length of time to evolve...we'd now be on a parched and baked Earth with no water. So the whole 'life arrived early' argument for life being common is really an anthropic fallacy. If life hadn't arrived early on this planet we wouldn't be here discussing it.

As for extremophiles, Kipping covers that too...and makes the valid point that just because life evolved to adapt to extreme environments does not mean it could start in them. A tardigrade, for example, is actually quite a complex creature that has evolved to be almost indestructible over billions of years.

Of course we should be looking for alien life. But in physics we have Departments of Theoretical Physics, where scientists speculate, and Departments of Physics, where scientists do empirical stuff. So maybe all those Departments of Exobiology should be renamed Department Of Theoretical Biology....and I'd be happy.

 

[Ann K]

So maybe all those Departments of Exobiology should be renamed Department Of Theoretical Biology....and I'd be happy.

No. Theoretical biology, if indeed is a matter of study, would be an entirely different thing. Exobiology is biology as we know it, just applied to a different planet, with the added difficulty of being unable to study it hands-on. It's still scientists doing empirical things.

Perhaps the field of exobiology does not encompass the task of making you happy.

 

[Scaramanga]

A macro-evolutionary direction towards increasingly more complex organisms -- from unicellular bacteria to multicellular algae, to plants, later from fish to reptiles, and from reptiles to birds and mammals -- is an observed fact. Not an opinion.

Once a more complex generic taxonomixal group or class had emerged, it has remained in existence in addition to simpler classes even if individual species within each class have gone extinct and been in a constant state of flux. Conversely, the earlier the fossil snapshot, the less do we have any evidence of these more complex classes.

Macro-deterministic directionality defined. Both ways.

To not see a direction towards general complexity in the above macro-process is an act of self-delusion prompted by a belief system whereby any and all directionality sends its proponents' alarm bells into a frenzy. They (entirely unnecessarily) begin to see an Evangelical Christian creator-god Bible-thumped on their heads from even the slightest evidence of teleology. An idea that need not be embraced in the least based on the mere technical fact of observed directionality towards complexity. Such a denial of directionality is all well and good in a free world, but in no way refutes the above-summarized clear evidence to the contrary.

I think there is too much of a tendency to see big creatures as complex and miss out on the huge complexity at the cellular level. Multi-cellular creatures are really just conglomerations of those single cells. Thus, most of the complexity of life is really at the cellular level...rather than looking at a T Rex and arguing that its huge so is way more complex than single cells. It is single cells....just lots of them.

 

[Scaramanga]

No. Theoretical biology, if indeed is a matter of study, would be an entirely different thing. Exobiology is biology as we know it, just applied to a different planet, with the added difficulty of being unable to study it hands-on. It's still scientists doing empirical things.

Perhaps the field of exobiology does not encompass the task of making you happy.

We will have to agree to differ. Personally, the actual name is a rather trivial side issue. It is the over-confidence of exobiology...the fact that barely a week goes by without some new moon or exoplanet on which there 'might' be independently evolved life....that is my bone of contention.

The problem is that we may never be able to determine with 100% certainty whether life found elsewhere in the solar system had an independent abiogenesis. We still don't know the exact process on Earth. Life on Mars may have come from Earth ( or even vice versa ). Even life in the oceans of Europa may have originated on Earth. Throw in panspermia and it all gets even more messy.

Thus we may never be able to determine the frequency of life in the universe as a whole, because even if our entire galaxy is teeming with life it may all have had a single incredibly rare abiogenesis just in our galaxy and been spread about over 9 billion years or so.

 

[Ann K]

We will have to agree to differ. Personally, the actual name is a rather trivial side issue. It is the over-confidence of exobiology...the fact that barely a week goes by without some new moon or exoplanet on which there 'might' be independently evolved life....that is my bone of contention.

I think that you'd find it is not the over-confidence of exobiology, but rather the over-hype of the headline writers. When the rocket bearing Curiosity rover blasted off, the announcer at the launch said something about "off to search for life on Mars", while the actual scientists just groaned and rolled their eyes. That narrative was in there to appease the members of congress (the people who approved their budget), who in their turn had to appease their voters. It would be a mistake to confuse the public face of the discussion with the actual work being done.

even if our entire galaxy is teeming with life it may all have had a single incredibly rare abiogenesis just in our galaxy and been spread about over 9 billion years or so.

The proof of that pudding would be (theoretically) finding another number of life-bearing planets and determining the age of both the planet and the length of time in which life had existed there, because of necessity there would be a gradient of time spans from the originating planet to those with a secondary colonization. You can file this under "things that we will never know in our lifetimes".

It's undeniable that a thing that is possible in one place can certainly be possible in other places. I fear the "earth only" proponents are often motivated by their desire to be considered "special and unique", whether that desire is motivated by ego or (for many people) theology. It can be hard to separate that desire from an honest assessment of the probabilities.

 

[Martinicus1]

Well Prof. Kipping deals with the 'life arrived early' fallacy in the video I posted earlier. It is yet another of those anthropic issues, because there's only really about 500-600 million years left for complex life on Earth..so life had to arrive early for there to be 4 billion years for complex life to arise. If life had arrived 500 million years later and taken the same length of time to evolve...we'd now be on a parched and baked Earth with no water. So the whole 'life arrived early' argument for life being common is really an anthropic fallacy. If life hadn't arrived early on this planet we wouldn't be here discussing it.

As for extremophiles, Kipping covers that too...and makes the valid point that just because life evolved to adapt to extreme environments does not mean it could start in them. A tardigrade, for example, is actually quite a complex creature that has evolved to be almost indestructible over billions of years.

Of course we should be looking for alien life. But in physics we have Departments of Theoretical Physics, where scientists speculate, and Departments of Physics, where scientists do empirical stuff. So maybe all those Departments of Exobiology should be renamed Department Of Theoretical Biology....and I'd be happy.

I actually never mentioned complex life. You call it the 'early life fallacy' and I don't think he refers to it in such terms. He also mentions that we cannot assume life elsewhere because we only have one example, but is happy to conclude, as are you, that intelligent life is likely to take them same amount of time to evolve elsewhere because it happened here. He also compares chemical reactions to snowflakes! Just to be pedantic, given enough time and enough snowflakes two identical is a certainty. Additionally, he talks about bias - I would argue that the special earth viewpoint is also likely influenced by bias due to our culture. He fails to mention this.

 

[LilWabbit]

I think there is too much of a tendency to see big creatures as complex and miss out on the huge complexity at the cellular level. Multi-cellular creatures are really just conglomerations of those single cells. Thus, most of the complexity of life is really at the cellular level...rather than looking at a T Rex and arguing that its huge so is way more complex than single cells. It is single cells....just lots of them.

Indeed, any serious and intelligent analysis of organismal complexity in biology avoids such purely size-based pitfalls (bold added):

Article:

To study the evolution of complexity in organisms, we need an understanding of complexity that enables us to measure it. In biology today, organismal complexity has two main operational senses: (1) a horizontal sense: the number of different part types at a given hierarchical level (e.g., the number of cell types in a multicellular individual) and (2) a vertical sense: the number of levels of nestedness of parts within wholes (e.g., a eukaryotic multicellular individual is one level of nestedness above a free-living protist). How do horizontal and vertical complexity behave in evolution? For horizontal complexity, an increasing trend is predicted by current theory, that is, by the zero-force evolutionary law (ZFEL), but at most hierarchical levels, evidence is lacking and the existence of a trend is uncertain. For vertical complexity, there is unambiguous evidence for a trend in the maximum, a rise in the maximum hierarchical level achieved by organisms over the history of life. However, the underlying mechanism of change and the forces driving the trend are unknown. Interestingly, there is some evidence that the rise in vertical complexity, the addition of new levels, is – when it occurs – accompanied by systematic losses in horizontal complexity at lower levels.

Source: https://link.springer.com/referenceworkentry/10.1007/978-3-319-32979-6_123

 

[Scaramanga]

I actually never mentioned complex life. You call it the 'early life fallacy' and I don't think he refers to it in such terms. He also mentions that we cannot assume life elsewhere because we only have one example, but is happy to conclude, as are you, that intelligent life is likely to take them same amount of time to evolve elsewhere because it happened here. He also compares chemical reactions to snowflakes! Just to be pedantic, given enough time and enough snowflakes two identical is a certainty. Additionally, he talks about bias - I would argue that the special earth viewpoint is also likely influenced by bias due to our culture. He fails to mention this.

No, I think it is somewhat erroneous for anyone to describe a rare Earth as in any way a 'special' Earth. In fact the entire specialness argument is somewhat topsy turvy, as anyone teleologically inclined could equally argue that a universe teeming with life indicated it was 'designed' to have life...rather than life just being a freak occurrence. Either way, the arguments are erroneous.

If people are rejecting rare Earth purely because they think it has theological connotations then that is wrong thinking. Sure, creationists can hijack ideas, but that does not in itself make those ideas wrong. Also it is worth adding that it is really only a handful of ultra orthodox fundamentalist Christians who have the 'there can't be other inhabited planets or Jesus would have had to die for them too' approach. Most Christians, in fact most religions in general, are quite happy with extraterrestrial life.

Personally I would love nothing better than for the universe to be teeming with all sorts of life. But I am highly skeptical of whether it actually is.

 

[Scaramanga]

I think that you'd find it is not the over-confidence of exobiology, but rather the over-hype of the headline writers. When the rocket bearing Curiosity rover blasted off, the announcer at the launch said something about "off to search for life on Mars", while the actual scientists just groaned and rolled their eyes. That narrative was in there to appease the members of congress (the people who approved their budget), who in their turn had to appease their voters. It would be a mistake to confuse the public face of the discussion with the actual work being done.

The proof of that pudding would be (theoretically) finding another number of life-bearing planets and determining the age of both the planet and the length of time in which life had existed there, because of necessity there would be a gradient of time spans from the originating planet to those with a secondary colonization. You can file this under "things that we will never know in our lifetimes".

It's undeniable that a thing that is possible in one place can certainly be possible in other places. I fear the "earth only" proponents are often motivated by their desire to be considered "special and unique", whether that desire is motivated by ego or (for many people) theology. It can be hard to separate that desire from an honest assessment of the probabilities.

I don't think even the most avid 'rare Earth' supporter is advocating Earth only. I'm also baffled by any notion of 'special', because if we are not relatively alone and the universe is teeming with life then all that really happens is the 'special' shifts from the Earth to the universe as a whole and the other end of the religious/teleology spectrum then start asserting it 'proves' the universe was designed for life. There'll be claims of specialness either way !

 

[NorCal Dave]

Maybe it's just me, but boy did this thread veer off. I find the various arguments for and against lots of aliens or no aliens and evolutionary biology and such very interesting. But it seems tangential to the OP claim: Does the sheer number of UFO sightings and photos offer compelling evidence that the Earth is being visited by aliens?

I suppose if the "rare Earth, no aliens" theory is true, then the answer is a resounding no. If the "lots of Earths, lots of aliens" theory is correct, then I think the answer is still no, but they could be out there.

Whether there are a few alien civilizations or multitudes, the evidence usually presented as proof that any of them are occasionally or routinely visiting Earth, is to my mind often dubious at best. Piling up a bunch of crap just results in a dung heap.

Sorry to interrupt .

 

[Mendel]

Maybe it's just me, but boy did this thread veer off. I find the various arguments for and against lots of aliens or no aliens and evolutionary biology and such very interesting. But it seems tangential to the OP claim: Does the sheer number of UFO sightings and photos offer compelling evidence that the Earth is being visited by aliens?

The scope kinda broadened into "can we make a mathematical argument for aliens", which is still not that far off topic given where other discussions have ended up. And it's actually the OP who derailed his own thread here: https://www.metabunk.org/threads/ar...ey-evidence-that-ufos-exist.12728/post-289769

The better thread for that topic is really https://www.metabunk.org/threads/bayesian-argument-to-believe-in-aliens.12400/

 

[John J.]

If a model doesn't even closely predict an observation, we have a problem.

Yes, the model might be inadequate.
Or, there is a fundamental flaw, or an extraordinarily significant omission, in our current understanding of evolutionary processes.
I suspect the former.

To be honest, I'm not aware of a mathematical "model of evolution" from a credible source which has caused the researchers to conclude that there must be an additional organising factor that has thus far been overlooked.
I think such a model would be extraordinarily ambitious (and highly contentious, considering our current understanding of abiogenesis and the emergence of eukaryotes, multicellular organisms and sexual reproduction).
However, I won't pretend to have done a literature trawl in this area!

I feel (LilWabbit) that you're claiming that there has been insufficient time for the current level of biological complexity to evolve according to mainstream theories- a claim which most suitably qualified people (biologists, geneticists, palaeontologists etc.) might disagree with. -That latter supposition of mine doesn't necessarily make you wrong, of course.
Your solution, to this problem that may well not exist, is to re-interpret what most people "in the field" might consider to be observed reality- essentially Darwinian gradualism, with an increased understanding of the role of small, isolated genepools in promoting speciation- to include a discrete (as opposed to emergent) driver for complexity, or at least a favouring of complexity in itself (as opposed to a favouring of traits resulting from genetic mutation or reproductive "shuffling", sometimes with concomitant genomic complexity).
Apologies if I have mis-represented your position!

Yet there's only a finite stretch of punctuated evolutionary periods during which these mutations are thought to have occurred at a certain averaged frequency to cause more complex species. Therefore the probability for even a single organism to produce mutated offspring falling within a narrow range of more complex favourable mutations is zero, let alone for their offspring to continue mutating favourably within mutant subpopulations into more complex and therefore less probable configurations.

Yet there's only a finite stretch of punctuated evolutionary periods

Even Eldredge and Gould didn't claim that all evolution occurred during "punctuation", not by a long way.
There are lots of examples of phyletic gradualism.

While there is a tendency for us to focus on the most dramatic "punctuative" events- the Cambrian explosion, the post K-T speciation- many (most) species may have undergone significant change (or indeed have evolved into a new species) as a chronospecies, without any "punctuative" events at all, or during a punctuation that primarily effects that species only and, while perhaps visible in the fossil record, might not coincide with major changes in the geological record (as evidenced in geological strata etc.)
A chance separation of a small breeding population- or even one breeding pair- from the rest of their genepool might be sufficient to enable speciation.

...which these mutations are thought to have occurred at a certain averaged frequency to cause more complex species.

By whom? And what is their evidence?
Plus, the existing variations of genotype within a species can permit evolution if selection pressures change, without mutation.

the probability for even a single organism to produce mutated offspring falling within a narrow range of more complex favourable mutations is zero

COVID-19 seemed to do a pretty good job of spreading itself about, mutations causing greater transmissibility.
Methicillin-resistant Staphylococcus Aureus has been favoured by the selection pressure of (inefficient) antibiotic use, and has spread globally.
Its even nastier offspring, vancomycin-resistant S.A., is only known from 1996- presumably driven by the use of vancomycin to treat MRSA.

Lactase persistence has evolved- probably several times in different locations, with differing mechanisms- in the past few thousand years in humans; north Europeans with the necessary mutation(s) gained a significant reproductive advantage over those who did not. The genetic basis of lactase persistence is reasonably well understood;
Genetic Signatures of Strong Recent Positive Selection at the Lactase Gene, Bersaglieri, T., Sabeti, P.C. et al, 2004,
American Journal of Human Genetics 74 (6), link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1182075/

let alone for their offspring to continue mutating favourably within mutant subpopulations into more complex and therefore less probable configurations.

No! A gene may be mutated, a population is a population.
A mutation that prevents a creature from reproducing is not beneficial pretty much by definition, so a beneficial mutation must enable its bearer to reproduce. It's then down to the genetic lottery (if the creature reproduces sexually) if that mutation is passed on to its offspring, giving them a genotype which includes the parent's mutation, and a physiology (and possibly phenotype) that reflects this, i.e. it inherits the beneficial trait.
A beneficial, heritable trait will spread, all other things being equal. But creatures bearing the new beneficial trait are not somehow immune to ongoing selection pressures or spontaneous genetic mutation; their increased complexity doesn't make further changes to the genome less probable!

Your (LilWabbit's) claim (more complex = less probable) reminds me of Fred Hoyle's "Junkyard Tornado"; he thought terrestrial abiogenesis was as likely as a tornado sweeping through a junkyard and leaving behind a Boeing 747.

Hoyle's fallacy contradicts many well-established and widely tested principles in the field of evolutionary biology.[5] As the fallacy argues, the odds of the sudden construction of higher lifeforms are indeed improbable. However, what the junkyard tornado postulation fails to take into account is the vast amount of support that evolution proceeds in many smaller stages, each driven by natural selection[6] rather than by random chance, over a long period of time.

https://en.wikipedia.org/wiki/Junkyard_tornado

Evolution is cumulative. Think of the example of eyes, which has to be repeated ad nauseum for creationists. (Who won't listen).
If you think it's impossible for increasing complexity to arise through natural selection, you don't believe in evolution
(not the scientific theory of evolution anyway).

Article: To study the evolution of complexity in organisms, we need an understanding of complexity that enables us to measure it. In biology today, organismal complexity has two main operational senses: (1) a horizontal sense: the number of different part types at a given hierarchical level (e.g., the number of cell types in a multicellular individual) and (2) a vertical sense: the number of levels of nestedness of parts within wholes (e.g., a eukaryotic multicellular individual is one level of nestedness above a free-living protist). How do horizontal and vertical complexity behave in evolution? For horizontal complexity, an increasing trend is predicted by current theory, that is, by the zero-force evolutionary law (ZFEL), but at most hierarchical levels, evidence is lacking and the existence of a trend is uncertain. For vertical complexity, there is unambiguous evidence for a trend in the maximum, a rise in the maximum hierarchical level achieved by organisms over the history of life. However, the underlying mechanism of change and the forces driving the trend are unknown. Interestingly, there is some evidence that the rise in vertical complexity, the addition of new levels, is – when it occurs – accompanied by systematic losses in horizontal complexity at lower levels. Source: https://link.springer.com/referenceworkentry/10.1007/978-3-319-32979-6_123

This is from Daniel W. McShea's "Evolution of Complexity", which was published as one chapter (of 86) in Evolutionary Developmental Biology, eds. L.N. de la Rosa and G.B. Muller, Springer Cham 2020,
link https://link.springer.com/referencework/10.1007/978-3-319-33038-9?page=2#about-authors
His paper has been cited twice.

He states,

...an increasing trend [in complexity] is predicted by current theory, that is, by the zero-force evolutionary law (ZFEL)

"Zero-force evolutionary law" sounded a bit dramatic to me, and I'd never heard of it, so I had a quick surf...

...the founder of this law is the same Daniel McShea, along with Robert N. Brandon, who described it in the book
"Biology's First Law", sub-title "The Tendency for Diversity and Complexity to Increase in Evolutionary Systems", 2010;
you can buy it here https://bibliovault.org/BV.landing.epl?ISBN=9780226562261

Now, I'm sure Dr McShea is a thoroughly decent chap, but I'm not sure he's quite the same rank as Darwin, Crick/ Franklin/ Watson or Pasteur.
The idea that "ZFEL" is in any sense "Biology's First Law" (even though he does say so himself!) is, of course, ridiculous.

In fairness, McShea and Brandon didn't claim (as far as I could see) that there is a need to invoke any extra-biological agency;
they do believe that

... in the absence of natural selection, an evolutionary system with variation and heredity will tend spontaneously to diversify and complexify.

"Zero -Force Evolutionary Law", Wikipedia, https://en.wikipedia.org/wiki/Zero-Force_Evolutionary_Law

Quite how you can have a real-world environment without natural selection, when you have variation and heredity as axiomatic, is not explained.

McShea seems to like "complexity" although his views about it seem to have changed rather a lot; in 1996's
Perspective Metazoan Complexity and Evolution: Is There a Trend? in Evolution 1996, 50 (2), he writes

In metazoans as a whole, there is good evidence only for an early-Phanerozoic trend, and only in one type of complexity.

(abstract here, https://pubmed.ncbi.nlm.nih.gov/28568940/)

No good evidence for a trend toward complexity since the early Phanerozoic?
There clearly is a trend; what we're discussing is whether it's the result of accumulated change due to the theory of evolution,
or whether it's due to some unidentified drive.

The probability of life arising on other planets is highly debatable (and interesting) but I'm not sure invoking metaverses or whatever in discussions of life on Earth will help much.
Let's get back to "Are all UFO reports wrong..."

 

[Mendel]

I believe that UFOs are real. There are hundreds, probably thousands of photos published in the 50's & 60's that show dozens of kinds of UFOs. They can't all be fake.

No, sir. What I mean is no different from Michio Kaku saying that the enormous number of planets now known or thought to exists makes extraterrestrial life of some kind near certain.

Foregoing the Drake equation, the simplified (controversial) extraterrestrial life argument looks like this:

1. There's a huge number of suitable planets.
2. We know 1 inhabited planet (Earth).
3. Therefore, it's likely that there are other inhabited planets.

The analogous reasoning fails at step 2 for UFOs:

1. There's a huge number of reports of UFO encounters.
2. We know 1 actual true UFO encounter.
3. Therefore, it's likely that some other UFO reports are true as well.

If we had a verified UFO sighting, the argument would be valid, but we don't.

You can't use statistics to show something exists when you don't have a single sample.

 

[LilWabbit]

Evolution is cumulative. Think of the example of eyes, which has to be repeated ad nauseum for creationists. (Who won't listen).
If you think it's impossible for increasing complexity to arise through natural selection, you don't believe in evolution
(not the scientific theory of evolution anyway).

Thank you for your lengthy response whereby you've at least made a good effort in studying more carefully what's written. You did miss several crucial points though, as well as certain basic facts about natural selection, which are demonstrated by misunderstandings and mischaracterizations such as the above.

Firstly, as is well-established, natural selection does not produce complexity but selects fitness amongst phenotypes, some of which are already complex or less complex per se. While it's true that natural selection is not a random process per se (due to known deterministic mechanisms of selection pressures such as natural disasters), and can be somewhat gradual (due to there being so many different kinds, levels and severities of pressures), the variance at which selective pressures operate within populations remains by and large random. The mechanism of what generates complexity in terms of how McShea and other biologists, quite soundly imo, define it, is largely unknown. However, the received theory hypothesizes that spontaneous genetic mutation is the sole/main cause. Evidence for complexification is found in fossil records which also evidence punctuation and a significant deviation from a gradualist emergence of complexity in the evolutionary sub-process of complexification. This type of non-gradualism is what Gould and Eldredge have studied and demonstrated and which punctuationists continue to argue as being firmly based in evidence.

Some confusion arises when we do not distinguish between complexification (caused by spontaneous genetic mutation according to received theory) and adaptation (caused by natural selection) as two sub-processes of the same overall process of evolution. You seem to conflate these two together in your counter-argument and hence it fails to really hit the mark. These parameters operating within a finite time period within our finite biosphere cannot mathematically account for our existence under the assumption of an open-ended experimentation of an infinite catalogue of configurations. No matter how gradualist the process and long the time period. Any amount of finite time just isn't mathematically enough.

So to repeat even more clearly: (1) Either the catalogue of possible configurations is not infinite, or (2) then there's an infinite amount of space and/or time available for such an open-ended experimentation as is argued, for example, by infinite multiverse theorists. An infinity of random experiments in different bubbles can mathematically account for a situation whereby the one bubble where we happen to hit the jackpot is bound to be the one where we have observers ending up wondering about this not-so-amazing coincidence in the final cosmic analysis (i.e. the anthropic principle).

The argument for Intelligent Design advanced by Christian apologists (et al) which appeals to so-called "irreducible complexity" is not only unable to logically refute the anthropic principle, but irrelevant to the 'complexity' I've been discussing in the above.

It seems to me that you and some others posters have mainly followed and discussed the topic of evolution in the (imho unhealthy and unnecessary) context of atheism-theism debates, resulting in somewhat ingrained (difficult-to-shake-you-out-of) ideas about what's meant by terms such as 'complexity', 'natural selection' and 'chance' by any poster invoking them in the context of probability. Terms that mean something much more well-defined, and different, in more rigorous and academic biological analysis which these debates often entirely fail to appreciate. On both sides of the debate. Unfortunately it doesn't help that a great number of biologists themselves are way too invested and active in these debates, often entirely forsaking their trained academic intellectual rigour, reliance on evidence, and scientific impartiality. Even brilliant scientists often stoop to child-like reasoning when they encroach into philosophical territory. They're just not trained (or self-trained) in fundamental or axiomatic concepts such as infinity and existence. Hence just quoting and counter-quoting smart and academically accomplished people on 'evolution' recognized as "evolutionary biologists" doesn't get us very far in any of these discussions. We have to dig deeper in the definition of concepts and the citation of experts in the right context.

By 'complexity' I'm not (nor is McShea or evolutionary biologists in general) making any reference, nor even an allusion, to the idea of 'irreducible complexity' invoked by intelligent designists. And by 'natural selection' I'm not suggesting an intellectually sloppy but all-too-common category mistake of including under its conceptual umbrella the complexity-generating process of 'genetic mutation'. The atheist side of such debates constantly falls prey to the latter confusion.

P.S. The eye has indeed been invoked by IDists too often without realizing it doesn't refute a non-ID hypothesis which provides for an infinite catalogue of options for random experimentation. But the IDists are not wrong in stating that a complex and flexible organ like the eye has a positive selective value only when it is more or less fully formed. Imagine the process of evolving an eye beginning with, say, a mutation-generated light-sensitive spot on the skin. Under most conceivable environmental circumstances such a spot would increase the vulnerability of the organism without conferring any immediate selective advantage, and such would be the case for a huge number of generations during which a huge number of further, favourable, mutations would have to occur. Moreover, the subsequent favourable mutations would have to occur among the already mutated population for there to be any evolution towards higher complexity. This requirement multiplies the individual probabilities for mutation, rendering such a process even less likely (and to a significant extent).

However, any theory which logically provides for the possibility that there has already occurred a random experimentation of an infinity of options can be invoked to account for such an otherwise improbable occurrence as the evolution of the eye. Various brands of the infinite multiverse theory are often propounded to do just that.

 

[Ann K]

But the IDists are not wrong in stating that a complex and flexible organ like the eye has a positive selective value only when it is more or less fully formed.

To quote Darwin's On the Origin of Species,

... if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist, each grade being useful to its possessor, as is certainly the case; if further, the eye ever varies and the variations be inherited, as is likewise certainly the case and if such variations should be useful to any animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, should not be considered as subversive of the theory.

It's patently obvious to me (as it was to Darwin) that the simple ability to distinguish light from dark is advantageous to any burrowing animal who wishes to hide, for example, and sensing the mere direction of movement of a predator allows its prey to dodge. The ID interpretation does indeed make statements like yours merely to push the thoroughly discredited notion of "irreducible complexity", and it surprises me that you repeat it.

Edit to add your statement -

"Moreover, the subsequent favourable mutations would have to occur among the already mutated population for there to be any evolution towards higher complexity."

The population by that time IS the "already mutated population". Duh.

You also claim that -

"These parameters operating within a finite time period within our finite biosphere cannot mathematically account for our existence under the assumption of an open-ended experimentation of an infinite catalogue of configurations. No matter how gradualist the process and long the time period. Any amount of finite time just isn't mathematically enough."

I think first you need to address the comment from @John J., and I'm not aware that you have yet done so -

"To be honest, I'm not aware of a mathematical "model of evolution" from a credible source which has caused the researchers to conclude that there must be an additional organising factor that has thus far been overlooked.
I think such a model would be extraordinarily ambitious (and highly contentious, considering our current understanding of abiogenesis and the emergence of eukaryotes, multicellular organisms and sexual reproduction)."

 

[LilWabbit]

To quote Darwin's On the Origin of Species,

... if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist, each grade being useful to its possessor, as is certainly the case; if further, the eye ever varies and the variations be inherited, as is likewise certainly the case and if such variations should be useful to any animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, should not be considered as subversive of the theory.

This statement by Darwin in no way contradicts anything I wrote.

It's patently obvious to me (as it was to Darwin) that the simple ability to distinguish light from dark is advantageous to any burrowing animal who wishes to hide,

If you refer to the likes of moles, you're already assuming an earlier evolution of a fully formed eye which re-adapted and de-evolved into a blind or semi-blind functionality. Not a very good counter-example.

for example, and sensing the mere direction of movement of a predator allows its prey to dodge. The ID interpretation does indeed make statements like yours merely to push the thoroughly discredited notion of "irreducible complexity", and it surprises me that you repeat it.

Seemingly so. But the apologist argument for 'irreducible complexity' doesn't regard chance mutation as even a theoretically possible explanans for the evolution of the eye. Without your palpable bias, you would have realized this significant difference as well in what I wrote and what the apologists suggest. Inability or unwillingness to appreciate conceptual nuance creates these types of misreadings repeatedly. It's caused by your own ideological positioning against anything which has even a whiff of something that you associate with theism. And this positioning of yours undermines your scientific objectivity in a palpable way.

Edit to add your statement -

"Moreover, the subsequent favourable mutations would have to occur among the already mutated population for there to be any evolution towards higher complexity."

The population by that time IS the "already mutated population". Duh.

It seems to me you didn't understand the transgenerationally decreasing sample-size inherent in the original statement.

You also claim that -

"These parameters operating within a finite time period within our finite biosphere cannot mathematically account for our existence under the assumption of an open-ended experimentation of an infinite catalogue of configurations. No matter how gradualist the process and long the time period. Any amount of finite time just isn't mathematically enough."

I think first you need to address the comment from @John J., and I'm not aware that you have yet done so -

"To be honest, I'm not aware of a mathematical "model of evolution" from a credible source which has caused the researchers to conclude that there must be an additional organising factor that has thus far been overlooked.
I think such a model would be extraordinarily ambitious (and highly contentious, considering our current understanding of abiogenesis and the emergence of eukaryotes, multicellular organisms and sexual reproduction)."

If you read attentively and without bias, you'll realize that my statement cited by you adequately addressed precisely the mathematical dilemma at issue. It's not only a response of a kind to John but a precise one.

 

[Mendel]

If you refer to the likes of moles, you're already assuming an earlier evolution of a fully formed eye which re-adapted and de-evolved into a blind or semi-blind functionality. Not a very good counter-example.

She wasn't, though. I thought of Earthworms.

Article:

The earliest predecessors of the eye were photoreceptor proteins that sense light, found even in unicellular organisms, called "eyespots".[21] Eyespots can sense only ambient brightness: they can distinguish light from dark, sufficient for photoperiodism and daily synchronization of circadian rhythms. They are insufficient for vision, as they cannot distinguish shapes or determine the direction light is coming from. Eyespots are found in nearly all major animal groups, and are common among unicellular organisms, including euglena.

At a cellular level, there appear to be two main types of eyes, one possessed by the protostomes (molluscs, annelid worms and arthropods), the other by the deuterostomes (chordates and echinoderms).[22]

Developing an optical system that can discriminate the direction of light to within a few degrees is apparently much more difficult, and only six of the thirty-some phyla[note 2] possess such a system. However, these phyla account for 96% of living species.[22]

After the photosensitive cell region invaginated, there came a point when reducing the width of the light opening became more efficient at increasing visual resolution than continued deepening of the cup.[10] By reducing the size of the opening, organisms achieved true imaging, allowing for fine directional sensing and even some shape-sensing. Eyes of this nature are currently found in the nautilus.

Source: https://en.m.wikipedia.org/wiki/Evolution_of_the_eye

These are excerpts from a long, thorough wikipedia entry.

 

[LilWabbit]

She wasn't, though. I thought of Earthworms.

Article:

The earliest predecessors of the eye were photoreceptor proteins that sense light, found even in unicellular organisms, called "eyespots".[21] Eyespots can sense only ambient brightness: they can distinguish light from dark, sufficient for photoperiodism and daily synchronization of circadian rhythms. They are insufficient for vision, as they cannot distinguish shapes or determine the direction light is coming from. Eyespots are found in nearly all major animal groups, and are common among unicellular organisms, including euglena.

At a cellular level, there appear to be two main types of eyes, one possessed by the protostomes (molluscs, annelid worms and arthropods), the other by the deuterostomes (chordates and echinoderms).[22]

Developing an optical system that can discriminate the direction of light to within a few degrees is apparently much more difficult, and only six of the thirty-some phyla[note 2] possess such a system. However, these phyla account for 96% of living species.[22]

After the photosensitive cell region invaginated, there came a point when reducing the width of the light opening became more efficient at increasing visual resolution than continued deepening of the cup.[10] By reducing the size of the opening, organisms achieved true imaging, allowing for fine directional sensing and even some shape-sensing. Eyes of this nature are currently found in the nautilus.

Source: https://en.m.wikipedia.org/wiki/Evolution_of_the_eye

These are excerpts from a long, thorough wikipedia entry.

These statements in no way address the improbability of this very process by an open-ended random mutation within a finite time period and finite space. Rather these facts strongly suggest a finiteness of possible configurations for random mutation unless we assume an infinite multiverse or something to the same effect.

Which is not the irreducible complexity argument. I'm not denying randomness here.

 

[Ann K]

This statement by Darwin in no way contradicts anything I wrote.

It contradicts precisely the quotation of yours to which I applied it.

seems to me you didn't understand the transgenerationally decreasing sample-size inherent in the original statement.

If mutation number one is advantageous, the resultant population of organisms INCREASES in sample size. That's the definition of "advantageous" in regard to evolution and selection.

As to your insistence that mathematics can define biology (and, I think, a misuse of the concept of "infinite") we are still waiting for you to produce a justification for that claim.

It's caused by your own ideological positioning against anything which has even a whiff of something that you associate with theism.

I'm a scientist at heart, and want to find scientific reasons for observable fact. I'm not against theists themselves, but I know perfectly well that the scientific sphere is not the place for theology. Unless and until theology can provide even a SINGLE instance of the best answer to a scientific question being "god did it", I am quite content to ignore that field as providing any answers. How could a scientist do otherwise? I know, it's easy for you to dismiss my statements on that as being a bias caused by "ideological position", but I feel exactly the opposite position is itself a completely unwarranted bias which is unworthy of any serious discussion of facts.

 

[Mendel]

These statements in no way address the improbability of this very process by an open-ended random mutation within a finite time period and finite space. Rather these facts strongly suggest a finiteness of possible configurations for random mutation

Please explain. I don't follow your "strongly suggest" at all.
Note that the mutations are coded on the genotype.

 

[LilWabbit]

Please explain. I don't follow your "strongly suggest" at all.

Because mutations are random occurrences. By mutation here is meant spontaneous genetic change whereby any allele possessed by an offspring is not present in (either) parent.

Also your citation of the "earliest predecessors of the eye" should not be confused with a radiation-induced mutation of a region of skin into a light-sensitive spot which acts as a disadvantegous intermediary phase towards even those earliest predecessors of the eye which have an actual advantegous functionality. You're still referring to a type of final adaptation rather than the short-lived mutant intermediaries. The 'eyespots' of unicellular organisms are just a more primitive type of final adaptation along their specific evolutionary paths.

Note that the mutations are coded on the genotype.

Incorrect, and hence some of the repeated misunderstandings and misreadings.

Article:

Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining),[2] cause an error during other forms of repair,[3][4] or cause an error during replication (translesion synthesis).

Source: https://en.m.wikipedia.org/wiki/Mutation

 

[Scaramanga]

Maybe it's just me, but boy did this thread veer off. I find the various arguments for and against lots of aliens or no aliens and evolutionary biology and such very interesting. But it seems tangential to the OP claim: Does the sheer number of UFO sightings and photos offer compelling evidence that the Earth is being visited by aliens?

I suppose if the "rare Earth, no aliens" theory is true, then the answer is a resounding no. If the "lots of Earths, lots of aliens" theory is correct, then I think the answer is still no, but they could be out there.

Whether there are a few alien civilizations or multitudes, the evidence usually presented as proof that any of them are occasionally or routinely visiting Earth, is to my mind often dubious at best. Piling up a bunch of crap just results in a dung heap.

Sorry to interrupt .

The evidence for aliens would be amazing, but, the aliens have secret technology that forces people to use the cheapest, low grade, blurry image, wobbly, visual capturing equipment possible and only use it when the UFO is 50 miles away. All those reports where the UFO is a mile wide and hovering overhead and one can see the rivets in the thing are from just before the aliens used their secret technology to prevent humans getting good evidence