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One or two contributors have cited the unaccountably popular principle that "Absence of evidence is not evidence of absence". - With respect I must challenge the veracity of this principle. - If there are no piles of dung on the doorstep, no large footprints on the carpet, and no sound of trumpeting from the kitchen, I feel justified in concluding that there is no elephant in the house. Of course I may then find that there is a small, well-behaved, house-trained elephant in the kitchen, but my surprise at finding it there will be justifiable. - Generally speaking, the absence of the most likely traces to be left by something are prima facie support for the likely absence of that something. This of course is probabilistic reasoning, which is often found unsatisfactory to those who seek certainty and want everything to be clear in black and white, yes or no, true or false, terms. - Outside logic and mathematics (and even inside logic and mathematics sometimes) nothing can ever be absolutely certain. All our knowledge is based on assessment of probabilities. The problem with agnosticism is that instead of accepting that there is a whole gradation of probabilities (from 0 = certainly false to 1 = certainly true) it recognises only the midpoint (1/2 = 0.5 = we don't know for certain).

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George Jellis challenges the principle of "absence of evidence is not evidence of absence", quoted by John Clinch in defence of abiogenesis. I agree totally with George's challenge, and suggest we should settle for the fact that absence of evidence is not evidence of absence or of presence. Then we can forget it. - George goes on to advocate probabilistic reasoning, "which is often found unsatisfactory to those who seek certainty and want everything to be clear in black and white, yes or no, true or false terms." I'd have thought most agnostics would be all in favour of probabilistic reasoning, as opposed to "true and false". But George then says: "the problem with agnosticism is that instead of accepting that there is a whole gradation of probabilities (from 0 = certainly false to 1 = certainly true) it recognises only the midpoint (1/2 = 0.5 = we don't know for certain)." - First of all, I'm not convinced (or don't know for certain!) that 0.5 = we don't know for certain. Most contributors, including yourself, seem to agree that in the context of theism versus atheism, we are not dealing with knowledge but with belief, and that "knowledge" is impossible. By that definition, we would all be agnostics. I think the definitions should make this clear: 0 = believed to be false; 1 = believed to be true; 0.5 = neither believed nor disbelieved to be false or true. (As usual, I'm referring to the 'unofficial' form of agnosticism as opposed to the 'official' Huxley form.) - Secondly, I myself have no difficulty recognizing that many people have less than a 100% belief or disbelief, but if on the scale of probabilities I find myself stuck at 50%, why is this a problem? And for whom? It would certainly be a problem for me to choose and defend one unlikely explanation and exclude other possible explanations. A more general "problem" may well arise if someone insists that one explanation is more likely than any other, and that the probability is so great that other explanations can only come from people who need to "grow up" or ... in the case of religious fundamentalists ... need to be taught a lesson. - Thirdly, may I point out that the thread under "Atheism" deals precisely with gradations, and I'm glad we have come back to the subject. I suggest that we reopen this thread, as it has a number of important implications. For instance, if you rate yourself as 75% convinced that life began by chance, exactly what does the other 25% consist of? I would like to think that the sliding scale discussed here would create areas of common ground and a basis for tolerance in place of the one-sidedness that sometimes spills over into what Peter P. calls bigotry. - Having said that, though, I find it stimulating and illuminating to be told why one explanation seems more likely than another ... that after all is the purpose of our exchanging viewpoints ... and who knows, I may even one day be persuaded to shift from my 0.5.

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dhw writes: First of all, I'm not convinced (or don't know for certain!) that 0.5 = we don't know for certain. Most contributors, including yourself, seem to agree that in the context of theism versus atheism, we are not dealing with knowledge but with belief, and that "knowledge" is impossible. - I have a problem here with this distinction between knowledge and belief. As a rationalist I am committed to the principle that one's belief should be proportional to the evidence. One doesn't believe something just because one fancies it. That's wish-fulfilment. - 0 and 1 represent the absolute extremes of knowledge, certainly false and certainly true. Such absolute knowledge is really impossible, though belief that "1+1 = 2" comes as close to being certain as we can get. - 0.5 represents a situation where the evidence for and against a proposition is equal. It is just as likely to be true as to be false. This is an unusual situation of perfect balance. - The more usual situation is that we have good evidence, 90% or 99% or 99.9% (sorry to confuse the issue by changing from fractions to percentages), and can assess our degree of belief or knowledge appropriately. - If we are just confining our agnosticism to the concept of a life-creating being we need to examine what we know (with sufficient certainty) about life and about creative beings. We can say a good deal about the nature of life in terms of the elements and structures of which it is composed (DNA, cells etc). All we can say about creative beings is by analogy with human creators. We create gods in our own image (to invert the biblical saying). Human watchmakers have eyes and dextrous fingers and delicate tools, but who has seen the supposed creator's fingers or tools in action? - However I don't really want to go over that ground again. What I'm arguing about here is the nature of knowledge and belief and agnosticism in general terms.

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George Jellis writes: "One's belief should be proportional to the evidence." And: "The more usual situation is that we have good evidence...and can assess our degree of belief or knowledge appropriately." I agree with this, and when you say you have "a problem with this distinction between knowledge and belief" (referring to my previous response), I take your point. The borderlines, as we keep seeing over and over again on this website, are blurred. So too are the borderlines between what you call "good evidence" and other evidence. A clear-cut case in the discussions that have taken place between you and me would be natural selection, where we both agree that the evidence is "good" enough for us both to believe the theory. Alas, most other cases are not so clear-cut! - However, as you say, we needn't go over the rest of the ground again. It would, though, be interesting to hear how others define knowledge, belief, evidence and agnosticism in relation to one another, and I would be especially interested to have such definitions applied to the "near death experiences" to which David Turell has drawn our attention. The Pim van Lommel site might well set a few sparks flying.

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'One or two contributors have cited the unaccountably popular principle that "Absence of evidence is not evidence of absence". - 'With respect I must challenge the veracity of this principle.' - The popular principle points to the logical fallacy known as argumentum ad ignorantiam, in which it is claimed that a statement is true only because it has not yet been shown to be false or is false only because it has not been shown to be true. Two examples of this fallacy are the statements 'You can't prove God doesn't exist, so God exists.' and 'You can't prove God exists, so God doesn't exist.' Just as the absence of evidence of God's existence does not by itself constitute evidence that God doesn't exist, absence of evidence that God doesn't exist does not by itself constitute evidence that God exists. - Curiously, each side in the dispute between atheists and theists often castigates the other for committing this fallacy while committing it itself in the case of its own arguments. Atheists will quite happily point out that the fact science can't show that God doesn't exist isn't evidence of God's existence, and then blithely go on to argue that the fact believers can't prove God exists is evidence that God doesn't exist. And, of course, theists will argue the opposite. - The key phrases, however, are 'only' and 'by itself'. Absence of evidence in support of some statement can, alongside other evidence that positively supports its negation, provide us with some good reason to doubt the truth of that statement. The logician Irving Copi puts it this way: 'The argumentum ad ignorantiam [fallacy] is committed whenever it is argued that a proposition is true simply on the basis that it has not been proven false, or that it is false because it has not been proven true. He adds, A qualification should be made at this point. In some circumstances it can be safely assumed that if a certain event had occurred, evidence of it could be discovered by qualified investigators. In such circumstances it is perfectly reasonable to take the absence of proof of its occurrence despite searching, as positive evidence towards its non-occurrence.'

But even with this qualification it remains the case that absence of evidence is inconclusive and falls short of the requirements of knowledge. It may constitute a reasonable basis for belief, based on an evaluation of relative likelihoods, but not for a claim to knowledge.

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I stand justly criticised. - Re-reading the posting in which I used the rather trite phrase "Absence of evidence is not evidence of absence", I could have expressed myself better. I was making an obvious point badly and I hugely overplayed my hand. I was simply objecting to the dhw's apparent presuppositon that scientists would never uncover evidence about how life could rise from simpler physical forms. His is a hugely strong claim and the irony is that he does not have to make it to justify agnosticism. A classic case of a smart person using a rather silly reason to get to a conclusion that can be propped up in better ways. - But I do need to respond briefly to yours and Mr Whitecraw's epistemological points. The sentence would have made more sense, perhaps, had it read "Absence of evidence is not NECESSARILY evidence of absence". At heart, it's really just Hume's point isn't it? Just because you have experience that something is the case (here, a lack of evidence for abiogenesis) it does not follow as matter of logic or pure reason that you will continue to have that experience. - I disagree with Mr Whitecraw's criticism, though. It is not the argument from ignorance, surely, but its polar opposite. It's an expression of extreme scepticism: it is not saying "You have failed to prove X so Not-X must be true" so much as "You have failed to prove X but X could nonetheless be true". Here, it's saying that, as a matter of logic, we cannot conclude on the basis of our negative experience thus far that abiogenesis is impossible. This is NOT to support any positive point that abiogenesis will happen in the lab, but to criticise dhw for presupposing it to be forever impossible. (Contrary to dhw's posting in this thread, it is a rather important feature of his argument and really goes ot the heart of it). - But I do agree with Mr Jelliss. In the circumstances he outlines, OF COURSE we would be entitled to infer a conclusion about the absense of an elephant in our home. If we didn't use a similar approach to draw conlusions about reality, we could not conduct our lives and science (which is of course based on inductive reasoning) would crumble to nothing. - Incidentally, as to the unaccountable popularity of this expression, I blame the Iraq war when, after the invasion, proponents of the idea that there were WMD were caught saying "Absence of evidence...". The irony is that they later had to face up to the unavoidable conclusions of their own inductive experience: the contiuned absence of evidence BECAME evidence of absence - thus demonstrating the poverty of the phrase and that of purely deductive reasoning generally.

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John Clinch once again mentions my "apparent presupposition that scientists would never uncover evidence about how life could rise from simpler physical forms. His is a hugely strong claim..." - It would indeed be a hugely strong claim if I had ever made it. I'd be most grateful if you would point to the reference.

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I wasn't quoting you: I was paraphrasing, I thought fairly. - Your argument turns on abiogenesis being tantamount to an actual miraculous event or series of events ... i.e. something that science CANNOT IN PRINCIPLE explain. I say this because much of your home page is devoted to stressing what you regard as the limitations of science and drawing your conclusion from these limitations. It would seem to follow that the basis of your agnosticism falls away if science could explain abiogenesis. Fair? - You referred to what would be the miraculous creativity of pure chance. Specifically, as to the naturalistic explanation of life's origins, I found this: - "But how does life get started?" Again [Dawkins] admits that this "may have been a highly improbable occurrence". "The origin of life was the chemical event, or series of events, whereby the vital condition for natural selection first came about. The major ingredient was heredity, either DNA or (more probably) something that copies like DNA but less accurately, perhaps the related molecule RNA." This is an extraordinary simplification. The origin of life must at the very least have had two major ingredients, and they must have sparked into life at precisely the same moment: heredity was one, but what Darwin called the "breath" was the other. DNA is not much use in a lifeless body. By only calling on DNA/RNA, at a stroke Dawkins has halved the degree of the already high improbability. But be reassured: "I shall not be surprised if, within the next few years, chemists report that they have successfully midwifed a new origin of life in the laboratory" (p. 137). That's OK then. Dawkins thinks that the combined knowledge of the finest brains, working on the findings of generations of earlier fine brains, will soon be able consciously to put together the ingredients and breathe the spark of life into them ... which will prove that life came about through unconscious chance." - You do not develop the point, but the implication is clear enough: you don't believe Dawkins' claim. It is unclear whether you disagree with the view that life will be artificially created SOON or are saying that life will NEVER be artificially created. But, basically, you dispute that science can do it. Fair? - And in your posting, responding to me, you said: - "However, if scientists do eventually discover how life came about, and if the explanation turns out to be as simple and natural as you and George think, and chance does seem to be the best bet, then it may indeed influence my beliefs" - Set against this, I cannot see how my statement, referring to your - "apparent presupposition that scientists would never uncover evidence about how life could rise from simpler physical forms. His is a hugely strong claim..." - can, in fairness, be objected to. If you want to resile from your stated position, we need to know, but any reasonable reading of what you wrote tends to the view that you are, at the very least, extremely sceptical that science will ever fully explain life. I'm paraphrasing again, of course, but your argument is based on an assumption that it won't happen. Fair? - The declared basis for your agnosticism is the argument that you are faced with two very implausible options: the rock of the miracle of "creative chance" and the hard place of a miraculous intervention by God. That is to say, we are faced with two miraculous alternatives. It follows that, if there is ever good evidence of natural processes, there is no miracle. Fair? - I am amazed about your low expectations of science in this regard: its record over the last 300 years has been STAGGERING in what it can now explain and we may just, if we manage our planet properly, have a million or even a billion years of science ahead of us. Just pause and imagine that. Why do you need to speculatively posit the possibility of a miraculous intervention when there may be so much time left to understand what is, after all, just another aspect of Nature? The reality is that there are very good grounds to suppose that science WILL be able to fully explain how life originated. My interventions in this debate have been to try to understand why, in the face of that, you persist with saying we only have two miraculous alternatives. - Remember, not one single miracle has ever been verified. ALL phenomena of Nature observed thus far have been due to entirely natural processes and we have no good reason to suppose that any will not be. Applying Ockham's razor, there is no need to postulate the possibility of a designer to explain the origin of life on this planet. Ergo, although there may be a good reason for being an agnostic (and I believe that there are), yours isn't one of them.

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Many thanks for your detailed explanation, which makes clear how the misunderstanding has arisen. No, your paraphrase is not accurate. In fact you have completely missed the point. You quote me: "Dawkins thinks that the combined knowledge of the finest brains, working on the findings of generations of earlier fine brains, will soon be able consciously to put together the ingredients and breathe the spark of life into them...which will prove that life came about through unconscious chance." The point that I make here, and again and again in the "guide", and which I have chosen as one of two forms of "madness" with which to conclude it, is that if it needs supreme intelligence to understand, let alone recreate something, one can hardly take that as proof that the original creation needed no intelligence at all. - There is no presupposition on my part about what scientists will be able to achieve. Physical life exists, it must have had an origin, and of course science will advance in its understanding of the origin. But if it takes a supreme degree of consciousness to understand life and perhaps one day to recreate it, I don't see how you can be so certain that it didn't need consciousness to create it in the first place. You have taken your "leap of faith" that science will eventually support your belief in the creative genius of unconsciousness. I keep my options open. - This is only half the problem, though. I have equal difficulty with the notion of George's famous Grand Old Designer. We needn't go into that now, since you have the same difficulty. The difference between us, however, is that since I lack your faith, I am willing to consider other options and their implications (e.g. the possibility of different forms of existence, which this website has just got onto under the thread of Near to Death Episodes). - What is a "good reason" for being an agnostic? My inability to decide whether the world is a product of accident or design is not the only problem, as you would see from different sections of the "guide", but it is a hugely influential factor. If it seems a poor reason to you, that is because you already know what science will discover, whereas I don't!

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As I read through this thread on the absence of evidence, I am struck by the fact that no presentation of scientific findings is offered to be considered, that might be viewed as 'evidence'. All I see is a discussion in philosophic definitions. I am a former agnostic, who with my scientific background as a physician, decided to study the accepted evidence, and in many cases proven lack thereof, and I concluded there is evidence of 'something' behind the origin of the universe and of life. That 'something' is not God as created by mankind's religions. I was invited to visit this website by Clare Rooney, a member of the website coordiation team, because she came upon my website that discusses my book. I am really asking a question of this website. Does this group know the scientific effort expended since 1953 on the origin of life with no meaningful result? The Urey-Miller lightening in a bottle experiment was 1953. Fifty-five years ago. An excellent review was "Origins; A Skeptic's Guide to the Creation of Life on Earth", by Robert Shapiro, 1986. He is now a retired biology professor who spent his career in the field, and recently has published a provocative paper in Scientific American suggesting an approach with simpler chemicals, because of the lack on any progress. "Genesis" by Robert M. Hazen, 2005, is a recent presentation of the various competing theories, again admitting no progress. Should I offer my view of why I think there is no progress? Does that fit the purpose of this website discussion group?

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David Turell is "struck by the fact that no presentation of scientific findings is offered" on this website, and also asks if he should offer his view on why "there is no progress" in the field of how life began. - First of all, an emphatic yes please to your offer. George Jellis drew our attention to work being done in the field of abiogenesis, concerning which he and I had an exchange of views on the thread "Teapot Agnosticism" (3rd February, 4th February), but generally the discussion has, as you say, been more philosophical and badly needs to be opened out. You have already done this for us, and although I can only speak for myself, I would be grateful for more! - I still can't get the Lancet article by Pim Van Lommel, and although I have found a long list of entries about you on Google, it would save a protracted search if you would kindly give us the address of your own website.

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dhw would like to visit my website. It is: www.sciencevsreligion.net but it will not go into any great detail as it discusses the purpose of my book with just some content. The van Pommel Lancet paper is the first reference in the Toward the Light internet article by van Pommel given in dhw's entry of 2/28 in the near to death thread. He summarized his Lancet article very well, and that is all you need to read to see the scientific approach he used. I appreciate the OK to present scientific material to this group, and will do so when I have some time to sit and compose a concise presentation.

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A good reason for being an agnostic is to admit that nothing can be known about the nature of God, if God exists in the way that the term is normally understood. - That is the reason that, in that formal sense, I am an agnostic (to answer your question from another thread). However, to all intents and purposes, I am an a-theist since I do not believe in the God of the three monotheisms - i.e. traditional theism. The idea of God as a self-willed, autonomous conscious being I find ludicrous. The idea of God as Nature (Spinozistic pantheism), I am willing to explore. Panentheism is also a possibility. Are you a theist if you are a pantheist? I guess you are, though poor old Spinoza was persecuted as an atheist for his efforts. - So, theism's largely out but I cannot fully accept the rather poetic atheistic idea of a universe bursting into being, ex nihilo, like a flower from a quantum fluctuation for no reason, becoming conscious through its complex life-forms, and then dying for no reason. Why is matter potentially conscious? Why is it embedded in the very fabric of the universe that it has conscious expression? Why is dust vital? If it is ultimately meaningless (and it might be), I am appalled at the pointless plenitude of it. - I change my mind on this subject but I tend to come back to the idea that there has to be a context for the universe, a metaphysical reality of an unknowable kind beyond (or within) the material world. - So, I guess that makes me agnostic, a-theistic but admitting of a greater metaphysical context. Of all the religions texts, I think the Tao te Ching stands head and shoulders above the others in terms of expanding our understanding of ineffable ultimate reality. Even then it says nothing, quite literally. - A bad reason for being an agnostic, in my view, is to rely upon our failure (as yet) to understand a particular aspect of reality. Wittgenstein's remark is worth repeating here: it is not the things in the world that are mystical BUT THAT IT IS (I paraphrase). I agree. - And I completely disagree with your point about intelligences being required for the creation of something. The knock-out thing about evolution is that it answers a very difficult question (how complexity arises from simplicity) in a very simple, beautiful, economical and elegant way. Humans can't create lots of things: that don't mean nuthin.

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I am replying to this on a new thread. Our near to death thread is becoming rather tangled! George Jelliss raised the question of the nature of knowledge, belief and agnosticism, and this might help us separate some of the issues.

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John Clinch has stated: "The knock-out thing about evolution is that it answers a very difficult question (how complexity arises from simplicity) in a very simple, beautiful, economical and elegant way." I wish it were that simple. It is simple and elegant but may not be true. Darwin did not know of Mendel's genetic work, and did not know how complicated the biochemictry of living cells happen to be. The DNA/RNA research of the past 50 years has been incorporated into a Neo-Darwin Theory, which has run into all sorts of problems. First, fossils are not step-by-step. About 600 million years ago (mya) was the Avelon Explosion in which the Ediacarans appeared de novo, with many multicelluar forms and then fizzled out. This was followed by the Cambrian Explosion at 520 mya. Again out of nowhere, with about 50 progenitor forms for 36 of the 37 currently existing animal phylla. The 37th appeared a little later. These animals had several organ systems including eyes. A few million years later the sexual "Plant Bloom" appeared, as usual out of nowhere.
 The morphologic tree of life is not matched by DNA/RNA trees. Homologous/ analagous match-ups also have trouble; and so do biochemical trees. Gould and Eldridge proposed a "Punctuated Equilibrium" Theory to explain all the starts, stops and jumps. It is a nice name but no explanation.
 I suggest reading the following books to give some background to the discussion going on: "Life's Solution, Inevitable Humans in a Lonely Universe", by Simon Conway Morris of Cambridge, 2003, the world's leading paleobiologist; "The Evolutionists, The Struggle for Darwin's Soul", by Richard Morris, 2001; and "Evolution, A Theory in Crisis", by Michael Denton, 1986.
 There will be a conference held next year by many of the leading lights of the Neo-Darwin scientists to sort out what they can and try new approaches. This is a web story on that meeting: http://www.scoop.co.nz/stories/HL0803/S00051.htm - My own interpretation of all I have read is that the Darwin mechanism is information poor in its capacity to create new information and DNA/RNA is extremely information rich. After all chance mutation and then passive natural selection, looking at what is available to allow survival doesn't seem to create, just modify. This point of view is from the information theorists. I believe evolution occurred. It is hard to deny progressive fossil development in successive geologic layers. It is the mechanism I question. There are two key points in discussing agnosticism: The Big Bang Theory of a created universe, which allows life; and the appearance and evolution of life itself. The universe certainly looks created; life and the Darwin approach to understanding it are key to a deist or agnostic decision. If Darwin is not explanatory, then what?

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A wonderful example of just so stories, but new evidence may be narrowing the possibilities. A great discussion:

https://www.newscientist.com/article/2194728-how-the-zebra-got-its-stripes-the-problem-...

"When it comes to explaining why zebras have stripes, it’s best to remember that some issues are not black and white.

"Biologists have been debating the puzzle since Darwin’s time, but a study published on Wednesday offers further evidence for one of the most promising explanations: that the stripes deter biting flies.

"In the parts of Africa where zebras live, there are blood-sucking horseflies that carry lethal diseases such as trypanosomiasis. Clearly, zebras would do well to avoid being bitten. The idea is that the stripes somehow confuse the flies so that they don’t land on the zebras.

"A team led by Tim Caro of the University of California, Davis tracked captive zebras and horses at a site in England. Horseflies circled round both, but they landed on horses significantly more often. Putting striped coats on the horses’ bodies meant the horseflies landed there less often – but still landed on their heads, which were uncovered. The implication is that the stripes were having a real effect.

"The hypothesis backed by a lot of evidence, but does that mean it’s the only reason for a zebra’s stripes? Not necessarily. Some ideas don’t seem to stand up, notably the suggestion that the stripes help zebras cool down on hot days – if that were true, we would expect a lot more tropical animals to be stripy. But other ideas seem to have more to them.

"One which at first seems ridiculous is that the stripes are a form of camouflage. Obviously, zebras are not inconspicuous. But the stripes could create “dazzle camouflage”: overwhelming the predator’s visual system and making it hard to track the zebra’s movement. Think about the experience of watching a herd of zebras all dashing in different directions, and imagine trying to pick out one of them to bring down.

"The evidence here is mixed. A 2016 study suggested that the dazzle effect only really works if the stripes are parallel to the animal’s direction of travel, implying that zebra stripes don’t work this way. But this was based on tracking humans playing a computer game. A 2014 study, based on computer modelling of how moving zebras would appear to a predator, suggested that the stripes would be extremely confusing.

"There is also the simple possibility that the stripes are a signal. The message may not be for other zebras: in 2017, researchers suggested that the stripes signal to other grazing animals, encouraging them to graze alongside the zebras. Such mixed-species herds offer more protection against predators. For now this is only a hypothesis.

"Perhaps the most important point is that these studies can only tell us is why zebra stripes continue to exist today, not why they arose in the first place. Evolution is good at re-purposing things, so a body part may arise, be used for one purpose, and then end up being used for something entirely different.

"An obvious example is the lens of the mammalian eye, which probably arose simply as a protective cover for the retina and only later developed the ability to focus light, creating a sharper image – which is now its most “obvious” function. It may be that zebra stripes have a similarly complex history."

"There is something psychologically appealing about a single, clear explanation. That instinct doesn’t mean we are wrong to seek such things – sometimes just-so stories turn out to be correct – but this is one area where our biases can work against us."

Comment: Our imagined reasons can fool us. Clear proof is always required, but this is a good attempt.

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Trying to find them:

https://www.sciencedaily.com/releases/2023/06/230627123017.htm

"Animals* first occur in the fossil record around 574 million years ago. Their arrival appears as a sudden 'explosion' in rocks from the Cambrian period (539 million years ago to 485 million years ago) and seems to counter the typically gradual pace of evolutionary change. Many scientists (including Darwin himself) believe that the first animals actually evolved long before the Cambrian period, but they cannot explain why they are missing from the fossil record.

"The 'molecular clock' method, for instance, suggests that animals first evolved 800 million years ago, during the early part of the Neoproterozoic era (1,000 million years ago to 539 million years ago). This approach uses the rates at which genes accumulate mutations to determine the point in time when two or more living species last shared a common ancestor. But although rocks from the early Neoproterozoic contain fossil microorganisms, such as bacteria and protists, no animal fossils have been found.

***

"Lead author Dr Ross Anderson said: 'The first animals presumably lacked mineral-based shells or skeletons, and would have required exceptional conditions to be fossilised. But certain Cambrian mudstone deposits demonstrate exceptional preservation, even of soft and fragile animal tissues. We reasoned that if these conditions, known as Burgess Shale-Type (BST) preservation, also occurred in Neoproterozoic rocks, then a lack of fossils would suggest a real absence of animals at that time.'

"To investigate this, the research team used a range of analytical techniques on samples of Cambrian mudstone deposits from almost 20 sites, to compare those hosting BST fossils with those preserving only mineral-based remains (such as trilobites). These methods included energy dispersive X-ray spectroscopy and X-ray diffraction carried out at the University of Oxford'

***

"The researchers then applied these techniques to analyse samples from numerous fossil-rich Neoproterozoic mudstone deposits. The analysis revealed that most did not have the compositions necessary for BST preservation. However, three deposits in Nunavut (Canada), Siberia (Russia), and Svalbard (Norway) had almost identical compositions to BST-rocks from the Cambrian period. Nevertheless, none of the samples from these three deposits contained animal fossils, even though conditions were likely favourable for their preservation.

***

"Dr Anderson added: 'Mapping the compositions of these rocks at the microscale is allowing us to understand the nature of the exceptional fossil record in a way that we have never been able to do before. Ultimately, this could help determine how the fossil record may be biased towards preserving certain species and tissues, altering our perception of biodiversity across different geological eras.'

*''Animals' can be defined as multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals feed on organic matter, breathe oxygen, reproduce sexually, have specialized sense organs and a nervous system, and are able to respond rapidly to stimuli."

Comment: this study shows the desperate stage of Darwinian research to destroy the Cambrian gap. The Edicaran before the Cambrian is filled with forms. That gap is real and shown to be 410,000 years in length. When first animals appear doesn't change that.

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