85,000-year-old Finger Bone Complicates Understanding of African Migration(smithsonianmag.com)
smithsonianmag.com
85,000-year-old Finger Bone Complicates Understanding of African Migration
https://www.smithsonianmag.com/science-nature/rare-85000-year-old-finger-bone-could-complicate-our-understanding-african-migration-180968720/?no-ist
100 comments
Hey! I'm usually that guy, but in they are they are using "optically stimulated luminescence".
https://www.usu.edu/geo/luminlab/whatis.html
https://en.wikipedia.org/wiki/Luminescence_dating
I'm not an expert in the subject an I'm not an archeologist, but the method sounds good.
One of the parts is the decay of radioactive atoms. This is a very well known subject, it's very easy to model and it is not affected by pressure or temperature (unless you use ridiculous huge amounts).
The other part is about electrons trapped in the defects of crystals, and the conduction and valence band of crystals. This is also a well known subject, but it's more difficult to model. So IIUC after measuring the amount of "trapped" light they must irradiate each sample to calibrate the "trapping" ability of the material. This is not affected by usual variations of pressure and temperature. In particular the energy of the photons in sunlight is very different from the photons due to normal levels of heat. (At high temperature like more than 500°C or 900°F, that is possible near a fire, the difference between the energy of the photons is not so much and you have https://en.wikipedia.org/wiki/Thermoluminescence_dating . But the heat below a few inches of the floor under sunlight is not enough.)
As I said, I'm not an expert, but it looks like they are combining well known techniques and I guess that if you can enclose a bunch of Ph.D. students in a lab for 20 years with proper equipment, a few interesting samples and enough food, they will be able to rediscover this method.
If you want to find something shady here, I'd look at
> [Katerina] Harvati, who wasn’t involved in the research, said she would be cautious in definitively assigning the finger fossil a Homo sapiens identity due to the fact that its shape overlaps with other hominin species. [...]
https://www.usu.edu/geo/luminlab/whatis.html
https://en.wikipedia.org/wiki/Luminescence_dating
I'm not an expert in the subject an I'm not an archeologist, but the method sounds good.
One of the parts is the decay of radioactive atoms. This is a very well known subject, it's very easy to model and it is not affected by pressure or temperature (unless you use ridiculous huge amounts).
The other part is about electrons trapped in the defects of crystals, and the conduction and valence band of crystals. This is also a well known subject, but it's more difficult to model. So IIUC after measuring the amount of "trapped" light they must irradiate each sample to calibrate the "trapping" ability of the material. This is not affected by usual variations of pressure and temperature. In particular the energy of the photons in sunlight is very different from the photons due to normal levels of heat. (At high temperature like more than 500°C or 900°F, that is possible near a fire, the difference between the energy of the photons is not so much and you have https://en.wikipedia.org/wiki/Thermoluminescence_dating . But the heat below a few inches of the floor under sunlight is not enough.)
As I said, I'm not an expert, but it looks like they are combining well known techniques and I guess that if you can enclose a bunch of Ph.D. students in a lab for 20 years with proper equipment, a few interesting samples and enough food, they will be able to rediscover this method.
If you want to find something shady here, I'd look at
> [Katerina] Harvati, who wasn’t involved in the research, said she would be cautious in definitively assigning the finger fossil a Homo sapiens identity due to the fact that its shape overlaps with other hominin species. [...]
Thanks for the writeup. Makes sense, but requires some further thought on my part (re: comments below on validation using multiple methods).
Also I have no problem with the biology aspect as it is trivially verified what a human (or otherwise) bone looks like, composition etc
Also I have no problem with the biology aspect as it is trivially verified what a human (or otherwise) bone looks like, composition etc
Dude in a caravan 100 years ago gets finger cut off while harnessing camel.
Buried finger in sand.
At night. (thus leaving the sand 'unbleached' as the term is used in the optical luminescence field.)
Occam's razor.
Buried finger in sand.
At night. (thus leaving the sand 'unbleached' as the term is used in the optical luminescence field.)
Occam's razor.
Lol for people interested in Science, HN really likes to think Science is easy and done by idiots...
Armchair experts.
> Groucutt and the rest of the team used a number of dating methods to confirm the likely age of the Al Wusta finger. For the finger itself and the tooth of an ancient hippopotamus found nearby, they applied U-series dating
Quite a trick for some dude in a caravan 100 years ago to be able to simulate 85,000 years of radioactive decay.
Quite a trick for some dude in a caravan 100 years ago to be able to simulate 85,000 years of radioactive decay.
>"Quite a trick for some dude in a caravan 100 years ago to be able to simulate 85,000 years of radioactive decay."
I don't think it is usually the constant decay rate assumption that can go wrong. It is instead the assumption that the isotopes were being generated and deposited at the same rates way back then. This does depend on environmental factors.
I don't think it is usually the constant decay rate assumption that can go wrong. It is instead the assumption that the isotopes were being generated and deposited at the same rates way back then. This does depend on environmental factors.
I still not 100% sure because I can't read the research article, but from the press article it loos like they didn't find the bone in the middle of a pile of sand but in the middle of some dry mud that was at the bottom of a lake a looong time ago. With dry mud you an easily notice if someone has been digging there after the main part of the sediments was formed.
Some relevant parts:
> After all, fossilization on land is very rare; the water and wet sediments of the paleolake must have offered just the right protection from oxygen to preserve the bone.
> One possibility is that, at the time, it wasn’t a desert. While the Nefud is all sand and rock today, at the time of the Al Wusta fossil, the region was a savannah, covered in lakes and rivers thanks to summer monsoons. The multitude of animal bones found in the same location, from wild cattle to antelopes, suggest that game was plentiful. The lake itself lasted year round and offered a source of fresh water, though it may have come with risks as well as rewards: many of the faunal bones bore marks of carnivores’ teeth.
Some relevant parts:
> After all, fossilization on land is very rare; the water and wet sediments of the paleolake must have offered just the right protection from oxygen to preserve the bone.
> One possibility is that, at the time, it wasn’t a desert. While the Nefud is all sand and rock today, at the time of the Al Wusta fossil, the region was a savannah, covered in lakes and rivers thanks to summer monsoons. The multitude of animal bones found in the same location, from wild cattle to antelopes, suggest that game was plentiful. The lake itself lasted year round and offered a source of fresh water, though it may have come with risks as well as rewards: many of the faunal bones bore marks of carnivores’ teeth.
Reads like they found it near the surface:
------
"But researchers behind the recent Misliya discovery argue that the bone’s location on the surface rather than in the lake deposits below mean it might not correspond to that climactic period."
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"But researchers behind the recent Misliya discovery argue that the bone’s location on the surface rather than in the lake deposits below mean it might not correspond to that climactic period."
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> but have we ever verified our dating techniques over 5k years? 10k years?
Yes.
> What’s to say that the hot desert sun and strange weather patterns, radiation or whatever couldn’t skew the dating
Lots. For a start - only one of those would possibly affect the outcome of testing and would also be detectable.
> It seems further unlikely that such a bone from, 85k y/ago as they say, would be so close to the surface
Your incredulity doesn't affect the outcome one way or another and unless you want to dispute the fact that artifacts that are much older are often found on or close to the surface it's not based in any way to the real world.
> In mechanical engineering we don’t ever “trust” the calculations until they are thoroughly validated
And neither does the science around these dating techniques. In fact they're usually better supported than any engineering is.
> It seems backwards to hinge all our science on it when (AFAICT) it hasn’t even been validated itself!
And here's the thing: You're incredibly misinformed and that's why it makes no sense to you.
Yes.
> What’s to say that the hot desert sun and strange weather patterns, radiation or whatever couldn’t skew the dating
Lots. For a start - only one of those would possibly affect the outcome of testing and would also be detectable.
> It seems further unlikely that such a bone from, 85k y/ago as they say, would be so close to the surface
Your incredulity doesn't affect the outcome one way or another and unless you want to dispute the fact that artifacts that are much older are often found on or close to the surface it's not based in any way to the real world.
> In mechanical engineering we don’t ever “trust” the calculations until they are thoroughly validated
And neither does the science around these dating techniques. In fact they're usually better supported than any engineering is.
> It seems backwards to hinge all our science on it when (AFAICT) it hasn’t even been validated itself!
And here's the thing: You're incredibly misinformed and that's why it makes no sense to you.
> And neither does the science around these dating techniques. In fact they're usually better supported than any engineering is.
Given that the results of most if not all engineering can be directly tested, this seems unlikely.
Given that the results of most if not all engineering can be directly tested, this seems unlikely.
I believe his point is that these methods are contentious for various reasons (religious objection being an example) so they have been heavily scrutinized and where exceptions have been found so have explanations. While most engineering doesn't receive the same level of attention, even if it could.
> In fact they're usually better supported than any engineering is.
I don’t care who supports what in engineering. If you put a dozen [gauges, potentiometers, accelerometers] on a truck and drive it for 1,000,000km varying conditions and the data matches up with the cross derivation for each instruments relation to the other, it is no longer a case of “who supports” -> it is either _fact_ or not and completely indisputable.
But it doesn’t become “supported” data for dropping said truck out of a plane. That’s lunacy - a dozen things not accounted-for in the normal model will occur.
Our models might hold for a few thousand years, maybe even 10k .. but how many times have we dated an >20k year artifact under varying conditions and been able to validate it without relying on another model?
Or as they would say about FEA, crap in, crap out (even though multiple models may agree, none are validated in such a method).
I don’t care who supports what in engineering. If you put a dozen [gauges, potentiometers, accelerometers] on a truck and drive it for 1,000,000km varying conditions and the data matches up with the cross derivation for each instruments relation to the other, it is no longer a case of “who supports” -> it is either _fact_ or not and completely indisputable.
But it doesn’t become “supported” data for dropping said truck out of a plane. That’s lunacy - a dozen things not accounted-for in the normal model will occur.
Our models might hold for a few thousand years, maybe even 10k .. but how many times have we dated an >20k year artifact under varying conditions and been able to validate it without relying on another model?
Or as they would say about FEA, crap in, crap out (even though multiple models may agree, none are validated in such a method).
> it is either _fact_ or not and completely indisputable.
Not really. You're all over the place. I don't know why you think engineering is some kind of special branch that is not susceptible to the model breaking down even after repeated testing? Products of engineering fail all the time. Was it "bad engineering" or is "engineering bad"?
All of engineering lives up the abstract tree where you can "take things for granted" about materials, their properties and the repeatability of operation and use of things like transistors, resistors, tensile strength of beams, elasticity properties, etc. "Good engineering" takes into account tolerances and failure points. So then why do products built on these assumptions fail in the field all the time? Because engineering models are built upon assumptions that fail. You then incorporate these failure modes and get better at it. Just like everyone else.
>Our models might hold for a few thousand years, maybe even 10k .. but how many times have we dated an >20k year artifact under varying conditions and been able to validate it without relying on another model?
Because once something is validated and established, people don't waste their time re-testing it unless there is a specific reason to. Can you give a specific reason why it should be retested? What data have you produced that doesn't fit in the model? Or what changes in the model do you propose so that the new model best explains the current data? Or do you want to scrap everything? What is your reasoning?
For someone who has no expertise in the field, its rather odd you seek to cast doubt on something you don't understand, rather than asking a question that will inform your understanding.
Not really. You're all over the place. I don't know why you think engineering is some kind of special branch that is not susceptible to the model breaking down even after repeated testing? Products of engineering fail all the time. Was it "bad engineering" or is "engineering bad"?
All of engineering lives up the abstract tree where you can "take things for granted" about materials, their properties and the repeatability of operation and use of things like transistors, resistors, tensile strength of beams, elasticity properties, etc. "Good engineering" takes into account tolerances and failure points. So then why do products built on these assumptions fail in the field all the time? Because engineering models are built upon assumptions that fail. You then incorporate these failure modes and get better at it. Just like everyone else.
>Our models might hold for a few thousand years, maybe even 10k .. but how many times have we dated an >20k year artifact under varying conditions and been able to validate it without relying on another model?
Because once something is validated and established, people don't waste their time re-testing it unless there is a specific reason to. Can you give a specific reason why it should be retested? What data have you produced that doesn't fit in the model? Or what changes in the model do you propose so that the new model best explains the current data? Or do you want to scrap everything? What is your reasoning?
For someone who has no expertise in the field, its rather odd you seek to cast doubt on something you don't understand, rather than asking a question that will inform your understanding.
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I can't say anything about this particular method, but as far as I know generally dating methods are tested against each other.
For instance, when you dig something out if the ground, you can get a rough idea of how old it is just by looking at the layers of rock and material above and below it. We know something about how fast these layers can be deposited, and usually stuff further down is older (not always, but if the layering is disturbed there's often evidence of it). So if you find that your dating method makes no sense for objects with an obvious date range (based on where you find them) then your dating method is probably broken.
Obviously then if you take a leap over to objects that you find that you can only date in one way, you are taking a leap of faith. But in a few years, dating methods will come along that might let you test it in a different way entirely and either corroborate your first date or contradict it.
For instance, when you dig something out if the ground, you can get a rough idea of how old it is just by looking at the layers of rock and material above and below it. We know something about how fast these layers can be deposited, and usually stuff further down is older (not always, but if the layering is disturbed there's often evidence of it). So if you find that your dating method makes no sense for objects with an obvious date range (based on where you find them) then your dating method is probably broken.
Obviously then if you take a leap over to objects that you find that you can only date in one way, you are taking a leap of faith. But in a few years, dating methods will come along that might let you test it in a different way entirely and either corroborate your first date or contradict it.
There is the risk of cascading errors. You can take many examples of beliefs that persisted for many decades, or even centuries in times past, that were simply wrong. But these wrong beliefs were often supported by layer after layer of corroborating evidence. The issue of course is that a derivative measurement takes the original measurement as a given, and then creates new formulae based on the result of the first - so you end up with two things corroborating the same view, even though its wrong.
So I guess the question is what measurements are completely and absolutely independent? I don't recall in strata aging if the formation rate was alone used to determine age - so far as I recall the ages were dated by cross referencing known 'benchmarks', but then you've just created this very effect by assuming the age and then using that calibrate your method.
And for what it's worth, I am not suggesting that the dating or other methods are incorrect here. Just pointing out some possible issues in this logic.
So I guess the question is what measurements are completely and absolutely independent? I don't recall in strata aging if the formation rate was alone used to determine age - so far as I recall the ages were dated by cross referencing known 'benchmarks', but then you've just created this very effect by assuming the age and then using that calibrate your method.
And for what it's worth, I am not suggesting that the dating or other methods are incorrect here. Just pointing out some possible issues in this logic.
layering, if the ground is undisturbed, can only tell us how old something at least is. The object itself could be older than the soil it was found in. Take for example how every ancient artifact in a museum is older than the soil it sits upon. So it has its limits. Who is to say that some dead guy’s finger wasn’t handed down for millennia before getting picked up during a raid and tossed on the ground on the journey back as worthless junk? We can’t fathom.
As a developer, I see the absolute broken processes and driving forces in the software world and assume that it's not just unique to us. Apparently every other field is also overloaded with bugs, improper testing, and bad assumptions.
Archaeologist turned embedded dev here. It's not limited to software. But dating is one of the things we understand very well. The key is an immense, globally consistent data set collected by thousands of idiots (like me) who trekked to the ends of the earth for a sample or two. That data came from dozens of sources (soils, charcoal deposits, rocks, lake cores, tree cores, ice cores, bones, literature, oral histories, artifacts, etc), each with their formation processes and interpretive challenges. In some cases (such as radio- or thermo- dating), the process depends primarily on fundamental physical processes. If these models are wrong, We got incredibly lucky building computers and space probes on the same concepts. But we can compare cross-check that data with processes observable today (like erosion, sedimentation, dendrochronology, cores... etc). Those data sets are globally consistent. But, we can go a step further and cross-check both of them with ab initio computer models and human sources with all the context that implies. As expected, they pretty much all work out.
Virtually every area of science has contributed to the modern understanding of dating. If something is fundamentally wrong in that understanding, it would be exciting to put it mildly.
And yes, there are issues as well. I could go on for hours about them. But archaeology is both an old field and a highly self-critical one. Any idea that's survived awhile is probably either "close", wrong in some very subtle ways, or extraordinarily attractive to our particular, western academia.
Virtually every area of science has contributed to the modern understanding of dating. If something is fundamentally wrong in that understanding, it would be exciting to put it mildly.
And yes, there are issues as well. I could go on for hours about them. But archaeology is both an old field and a highly self-critical one. Any idea that's survived awhile is probably either "close", wrong in some very subtle ways, or extraordinarily attractive to our particular, western academia.
Standard physics isn't really up for question. Newtons Laws still apply in the general case.
My teachers never pretended that quantum physics was a fully understood, concrete field. A lot of what they said was prefixed with "we don't really know if this is how it works, but this is the model".
My teachers never pretended that quantum physics was a fully understood, concrete field. A lot of what they said was prefixed with "we don't really know if this is how it works, but this is the model".
> Newtons Laws still apply in the general case.
No, they apply (or, rather, are reasonable approximations) in the specific case of objects that aren't too small, and that don't move too fast relative to each other, etc. That is, the common case, but not the general one.
No, they apply (or, rather, are reasonable approximations) in the specific case of objects that aren't too small, and that don't move too fast relative to each other, etc. That is, the common case, but not the general one.
That sounds good, and is true, but comes with blistering caveats. First, the general case as he puts it, covers every macroscopic objects on and including Earth. It also covers microscopic objects until you reach particles, again on Earth, because of the energy scales involved. Everything from molecules to mammoths fit into this general case. If you charitably interpret “standard physics” [1] to include Relativistic and Quantum physics, then you cover everything in the universe that isn’t a black hole or less than or equal to 1.6x10^-45 meters, or at energies associated with the Planck epoch of the Big Bang.
We’re talking about archaeology, which is notably unconcerned with black holes or anything with a detectable de Broglie wavelength. I think that if were not going to be pedantic, and accept that we’re talking about physics as applied to Classical objects like finger bones, he’s right and there is little debate to be had. It we want to be a little pedantic we can say that QM is just about the best tested theory ever, and the rounding error left to quibble over isn’t a factor here.
If we want to be super pedantic we can point out that the “common” case on the scale of the universe is ultimately quantum-gravitational and therefore subject to physics that is not understood. Of course that majority is at distance scales we can’t access, or at energies or seem since the first second after the Big Bang. In that very very pedantic case you’re just as wrong as he is, but I think you’d rightly argue that it’s a pointless distinction in context. I’d agree with you.
[1] Standard physics isn't really up for question. Newtons Laws still apply in the general case.
We’re talking about archaeology, which is notably unconcerned with black holes or anything with a detectable de Broglie wavelength. I think that if were not going to be pedantic, and accept that we’re talking about physics as applied to Classical objects like finger bones, he’s right and there is little debate to be had. It we want to be a little pedantic we can say that QM is just about the best tested theory ever, and the rounding error left to quibble over isn’t a factor here.
If we want to be super pedantic we can point out that the “common” case on the scale of the universe is ultimately quantum-gravitational and therefore subject to physics that is not understood. Of course that majority is at distance scales we can’t access, or at energies or seem since the first second after the Big Bang. In that very very pedantic case you’re just as wrong as he is, but I think you’d rightly argue that it’s a pointless distinction in context. I’d agree with you.
[1] Standard physics isn't really up for question. Newtons Laws still apply in the general case.
The subject of, say, radio-isotopic dating in archaeology isn't a matter of classical effects on large objects. We're taking about sub-atomic effects over a period from many-generations up to geological time.
You don't ascribe to Popperian/falsification science? What is your model - AFAIAA it wouldn't be regarded as science by almost all scientists currently working (according to studies on philosophy of science held by currently working scientists).
All science is up for question, stuff that isn't questionable isn't science.
What you state reminds me of the scientists in the 1900s saying all science had been discovered.
All science is up for question, stuff that isn't questionable isn't science.
What you state reminds me of the scientists in the 1900s saying all science had been discovered.
We already know that Newtonian physics is wrong. It's just less wrong than its precursors.
If you haven't already, you should read Asimov's essay: The Relativity of Wrong (http://chem.tufts.edu/answersinscience/relativityofwrong.htm)
If you haven't already, you should read Asimov's essay: The Relativity of Wrong (http://chem.tufts.edu/answersinscience/relativityofwrong.htm)
If our knowledge is so incorrect, how did you manage to send your comment to me from across the world?
The sentiment you are expressing is very tempting, but it doesn't give credit to the knowledge we have actually acquired.
It's difficult to discern between the many levels of partial knowledge (as all knowledge is partial), but it's what we must do.
The sentiment you are expressing is very tempting, but it doesn't give credit to the knowledge we have actually acquired.
It's difficult to discern between the many levels of partial knowledge (as all knowledge is partial), but it's what we must do.
Because everything required to do that is testable. Radiocarbon dating is not just untested on the timescales we're using, but can probably be confounded by all sorts of things. It's a pretty good guess, and matches up with a lot of other stuff we know, but it's still a guess.
Sources? I'm pretty sure you are significantly overstating the uncertainty. The word "guess" is very misleading here.
Direct, completely unmediated observation is not the only way to acquire knowledge. It is definitely a very good method. However, we humans are also incredibly good at finding clever, credible ways of inferring things from indirect clues.
Direct, completely unmediated observation is not the only way to acquire knowledge. It is definitely a very good method. However, we humans are also incredibly good at finding clever, credible ways of inferring things from indirect clues.
There are enough anomalies in dating methods to question them. At the time scales we are looking at, we have little or no knowledge of the actual circumstances of the environment at the time. Every kind of dating methodology that goes outside of human history relies on very specific assumptions. If we are wrong about any of those assumption then our dating methodologies become unreliable.
Even inside human history, we make various guesses about when various events take place. The extant records that we use to date any particular item or event lead us, in many cases, to a best guess. How accurate this guess is - well, who really knows.
Quite often, there is conflict over when or even if certain events have occurred in the past. This is the nature of the lack of easily obtained records of the past. Even when there is extent documentation available, there is still conflict.
I take all the prognostications of dates in the far past as a guess, since we don't really know.
> However, we humans are also incredibly good at finding clever, credible ways of inferring things from indirect clues.
We are not as clever or even credible in a lot of what we do as humans. We are far too biased and political even in the fields of science and technology. That is just a part of our nature. If you looked at all the controversies over the last, what, 300 years, or we could look back over the last 2500 years and we'll see this rear its head many, many times.
I have stated the position that we should not be concerned that we are certain, but put in the efforts to keep investigating all areas for insight and further knowledge. It really doesn't matter if our models are incomplete and wrong as long as we keep moving forward. It's when we are certain that we lose the ability to move forward. In many areas in science (even in technology) we have become "certain" that our theories and models are correct. This is a problem and we need to address this.
Even inside human history, we make various guesses about when various events take place. The extant records that we use to date any particular item or event lead us, in many cases, to a best guess. How accurate this guess is - well, who really knows.
Quite often, there is conflict over when or even if certain events have occurred in the past. This is the nature of the lack of easily obtained records of the past. Even when there is extent documentation available, there is still conflict.
I take all the prognostications of dates in the far past as a guess, since we don't really know.
> However, we humans are also incredibly good at finding clever, credible ways of inferring things from indirect clues.
We are not as clever or even credible in a lot of what we do as humans. We are far too biased and political even in the fields of science and technology. That is just a part of our nature. If you looked at all the controversies over the last, what, 300 years, or we could look back over the last 2500 years and we'll see this rear its head many, many times.
I have stated the position that we should not be concerned that we are certain, but put in the efforts to keep investigating all areas for insight and further knowledge. It really doesn't matter if our models are incomplete and wrong as long as we keep moving forward. It's when we are certain that we lose the ability to move forward. In many areas in science (even in technology) we have become "certain" that our theories and models are correct. This is a problem and we need to address this.
“Beyond 40,000 years old, the sample is so small, and the contamination risk so great, that the margin of error is thousands of years. It would be like having a watch that told you day and night.”[1]
[1] http://discovermagazine.com/2016/jul-aug/scientific-dating-m...
[1] http://discovermagazine.com/2016/jul-aug/scientific-dating-m...
The quote is irrelevant, it's taken from a section about radiocarbon dating which wasn't used here. They used Uranium series dating which according to your own source:
> The uranium-thorium method is often helpful for dating finds in the 40,000- to 500,000-year-old range, too old for radiocarbon but too young for K-Ar or Ar-Ar.
> The uranium-thorium method is often helpful for dating finds in the 40,000- to 500,000-year-old range, too old for radiocarbon but too young for K-Ar or Ar-Ar.
Have you researched any of the science behind the dating techniques?
Yes, I am about to complete my second bachelors degree in engineering and have done a basic level of research Re: dating techniques and know that most dating techniques rely on atomic properties which could also (but currently understood not to?) be affected by ie alpha/b/UV radiation. Or perhaps even exposure to ie bacteria (we are only really beginning to understand the interaction between bacteria and atomic level structures .. as apparent by some headlines in last 5/y or so)
But I am by no means what you might classify as qualified or moderately familiar in this field.
But I am by no means what you might classify as qualified or moderately familiar in this field.
I once tried to look into this and came away thinking it was all very circular (tree rings calibrated to archeology used to calibrate radioisotopes used to calibrate tree rings). There seemed to be a lot of room for cherry picking which data was "good" vs "corrupted" until everything matched up.
Also it seemed to rely a lot on calibrating to the "known" date of ancient egyptian artifacts, which were in turn originally dated using the bible. Ie, if a radioisotope date from an artifact with a "known" date disagreed with that, it would be rejected.
I remember this guy being an important player: https://en.wikipedia.org/wiki/Joseph_Justus_Scaliger
Maybe I am just remembering it wrong or didn't look hard enough...
Also it seemed to rely a lot on calibrating to the "known" date of ancient egyptian artifacts, which were in turn originally dated using the bible. Ie, if a radioisotope date from an artifact with a "known" date disagreed with that, it would be rejected.
I remember this guy being an important player: https://en.wikipedia.org/wiki/Joseph_Justus_Scaliger
Maybe I am just remembering it wrong or didn't look hard enough...
> Maybe I am just remembering it wrong or didn't look hard enough...
From what you wrote, it's both.
From what you wrote, it's both.
Another thing is I remember is a problem with people citing their sources. It was one of those topics with tons of BS making it hard to get to the actual data.
Since you seem to know a lot about it, can you pick one artifact (I don't think it should matter much which one) and outline all the data available for it?
Since you seem to know a lot about it, can you pick one artifact (I don't think it should matter much which one) and outline all the data available for it?
This is literally something a basic Wikipedia page covers in excruciating detail with multiple sources.
Like... really basic research would get you further along in your studies. I see what you mean by “didn’t look hard enough”.
Please start there, I think you’ll see see more detail than I could hope to provide in one HN comment.
Like... really basic research would get you further along in your studies. I see what you mean by “didn’t look hard enough”.
Please start there, I think you’ll see see more detail than I could hope to provide in one HN comment.
The wikipedia page didnt, and isnt expected to, answer my questions, which were about the methodology.
For a given date given based on dendrochronology I wanted to know who collected the samples, how many were collected, which were included in the final dataset (why and why not), the software used to align the rings with other dendrochronologies, get to see those samples that were rejected, etc.
For a given date given based on dendrochronology I wanted to know who collected the samples, how many were collected, which were included in the final dataset (why and why not), the software used to align the rings with other dendrochronologies, get to see those samples that were rejected, etc.
Why on earth are you talking about dendrochronology? We're dealing with a finger bone.
The scientists in the featured article used a number of dating methods and the article specifically mentions Uranium–thorium Dating. Either way - the whole point of most of the quotes from the team is that they are verifying the data (and collection, and results, and so on) and aren't sure yet.
What you're describing is called "peer review" and any results will certainly include most - if not all - of the information you ask for.
The scientists in the featured article used a number of dating methods and the article specifically mentions Uranium–thorium Dating. Either way - the whole point of most of the quotes from the team is that they are verifying the data (and collection, and results, and so on) and aren't sure yet.
What you're describing is called "peer review" and any results will certainly include most - if not all - of the information you ask for.
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To someone less knowledgeable in that field, why do you say that?
Because they not only showed a poor recollection of what he did read (misremembering) but they showed less understanding of the topics involved than a 10 minute Wikipedia binge would provide (looking hard enough)?
I was hoping for some specificity.
I think you are mixing up some things. Tree-ring dating (dendrochronology) is certainly not depending on other methods of dating. It is based on the patterns of tree rings which is known for more than 10000 years back. For dating a find more confidently you can combine dendrochronology with other methods, but dendrochronological dating is not itself depending on other methods. The bible is certainly not involved, and I would love to see your source for this idea.
Your Wikipedia link does not say anything like what you are stating.
Your Wikipedia link does not say anything like what you are stating.
The way I remember is that 1 year -> 1 tree ring is more like an ideal than reality.
You can have a series of cold summers with no growth or warm winters with continuous growth. Either can lead to many years -> 1 ring. Or you can have multiple warm/cold periods in one year in which case you can have 1 year -> many rings.
As a result the samples that are used for dating need to be carefully chosen, and this has not been done independently of the other sources of data.
I also remember it was difficult to find the raw tree ring data (all the images they tried). What was available was only some final data on ring widths, this made me question their assessment that alignments of the various tree ring datasets could just be due to chance similarities.
You can have a series of cold summers with no growth or warm winters with continuous growth. Either can lead to many years -> 1 ring. Or you can have multiple warm/cold periods in one year in which case you can have 1 year -> many rings.
As a result the samples that are used for dating need to be carefully chosen, and this has not been done independently of the other sources of data.
I also remember it was difficult to find the raw tree ring data (all the images they tried). What was available was only some final data on ring widths, this made me question their assessment that alignments of the various tree ring datasets could just be due to chance similarities.
Who are "they" in this story? You are making some vague references here.
Sorry, don't remember anyone specific. I do remember there were only actually a few people/labs who seemed to be in control of the raw data though.
Perhaps start here: http://web.utk.edu/~grissino/itrdb.htm
Perhaps start here: http://web.utk.edu/~grissino/itrdb.htm
I suspect you have heard some arguments by young-earth creationists who wanted to cast doubt on dating methods in general. The links you provide certainly does not support any of the vague claims you make.
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IIRC, Egyptian sources were used because the consistency of Nile River flooding meant their calendars are likely the most accurate.
Interesting, but I don't really follow how flooding would be any more helpful than the seasons in general.
The answer is the same as my bank is demanding from me.
Deposits. Regular, periodic deposits.
Deposits. Regular, periodic deposits.
I still don't get it. Why would that help you keep a calendar when you already have the seasons?
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We can today verify certain dates by looking at the deposit records.
Sorry, but here is what I was responding to:
>"the consistency of Nile River flooding meant their calendars are likely the most accurate"
You seem to be talking about something different now.
>"the consistency of Nile River flooding meant their calendars are likely the most accurate"
You seem to be talking about something different now.
Because of the flooding the harvest was very consistent every year. And taxes and purchases were therefore very consistent. This provides a set of records based on the solar calendar, not subject to the whims of changing rulers.
This seems pretty dubious to me. In fact I'd think they would have less need for a good calendar since the proposed extremely regular harvests would happen regardless.
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Perhaps you need to turn that skepticism inward. There are good answers to your questions.
Yes the dating techniques are verified by corroborating it with a lot of other evidence such as tree rings as well as other dating methods, it's also well corroborated with entirely different fields like geology, history and physics.
As for being close to the surface, there are quite a few geological process that can come into play. There are places on earth that have fossils hundreds of millions of years old on the surface. This is not in any way remarkable.
> So I suppose a similar thing applies here in dating science, except, it’s impossible to validate for another thousand centuries
This sounds alarmingly like an argument you'd get out of Ken Ham. Are you a creationist that has trouble accepting an earth older than 6000 years? The debating style of asking seemingly probing yet actually well understood questions screams creationist (and climate change denialist) as well. You also fit the profile of creationist and climate change deniers, engineers that think they're smarter than the actually are and don't know what they don't know.
As for finds like this, despite the headline it's completely unremarkable and fits easily within what we know of human migrations: https://en.wikipedia.org/wiki/File:Human_migration_out_of_Af...
Yes the dating techniques are verified by corroborating it with a lot of other evidence such as tree rings as well as other dating methods, it's also well corroborated with entirely different fields like geology, history and physics.
As for being close to the surface, there are quite a few geological process that can come into play. There are places on earth that have fossils hundreds of millions of years old on the surface. This is not in any way remarkable.
> So I suppose a similar thing applies here in dating science, except, it’s impossible to validate for another thousand centuries
This sounds alarmingly like an argument you'd get out of Ken Ham. Are you a creationist that has trouble accepting an earth older than 6000 years? The debating style of asking seemingly probing yet actually well understood questions screams creationist (and climate change denialist) as well. You also fit the profile of creationist and climate change deniers, engineers that think they're smarter than the actually are and don't know what they don't know.
As for finds like this, despite the headline it's completely unremarkable and fits easily within what we know of human migrations: https://en.wikipedia.org/wiki/File:Human_migration_out_of_Af...
This kind of comment is flammatory and against HN etiquette (and should be removed).
I know you claim to be skeptical but see evidence to the contrary. You're not skeptical of yourself and of your limited knowledge and your not skeptical of your need to be skeptical (there are no extraordinary claims in this discovery).
I see no evidence that you are responding in good faith to any flaws in your reasoning, you're continuing to make an argument from incredulity. So I'm sorry if you're not a creationist (not as sorry as I'd be if you were), but when you look like a duck, argue like a duck and respond like a duck I start getting that duck vibe.
How about you respond to the points in your post:
> Not to be that guy, but I’m really starting to question the accuracy of dating techniques when they publish finds like this.
Why when they publish finds like this? There is nothing extraordinary about these finds, they sit comfortably inside what we know of human migrations.
> This finding is only significant because of the age, but have we ever verified our dating techniques over 5k years? 10k years?
You're arguing against archaeology, geology, history and nuclear physics here. Do you think all these branches of science are being dishonest?
> It seems further unlikely that such a bone from, 85k y/ago as they say, would be so close to the surface.
Why do you find this surprising? There a quite a few geological process that can result in this. Nearly all fossils we find are quite close to the surface.
I see no evidence that you are responding in good faith to any flaws in your reasoning, you're continuing to make an argument from incredulity. So I'm sorry if you're not a creationist (not as sorry as I'd be if you were), but when you look like a duck, argue like a duck and respond like a duck I start getting that duck vibe.
How about you respond to the points in your post:
> Not to be that guy, but I’m really starting to question the accuracy of dating techniques when they publish finds like this.
Why when they publish finds like this? There is nothing extraordinary about these finds, they sit comfortably inside what we know of human migrations.
> This finding is only significant because of the age, but have we ever verified our dating techniques over 5k years? 10k years?
You're arguing against archaeology, geology, history and nuclear physics here. Do you think all these branches of science are being dishonest?
> It seems further unlikely that such a bone from, 85k y/ago as they say, would be so close to the surface.
Why do you find this surprising? There a quite a few geological process that can result in this. Nearly all fossils we find are quite close to the surface.
I see more problems in deriving migration patterns by looking at a single individual ...
I'm also skeptical of the accuracy of these dating techniques until we have more evidence that corroborates their findings. That being said, I'm also very skeptical of the prevailing existing theories about the distant past as well. The dearth of concrete evidence from the distant past necessarily makes it difficult or impossible to make definitive statements. Skepticism and demand for evidence should always be our guiding light, no matter how widely accepted a theory is.
Not to be excessively cynical or downright insulting, (also, my knowledge of archaeology is feeble) but is there any way to verify that they found the bones there in the desert?
> The discovery is “a dream come true, because it supports arguments that our teams have been making for more than 10 years,”
Ten years of debate could be motive enough for some people to fabricate the finding.
EDIT: All that aside, assuming it is legitimate and we can trust the discovery, I definitely agree an absolutely phenomenal discovery
> The discovery is “a dream come true, because it supports arguments that our teams have been making for more than 10 years,”
Ten years of debate could be motive enough for some people to fabricate the finding.
EDIT: All that aside, assuming it is legitimate and we can trust the discovery, I definitely agree an absolutely phenomenal discovery
The odds that you could perfectly pull off such a stunt are very low, approaching zero asymptotically as time passes and scrutiny grows. For the thing to work everyone involved would need to be perfectly able to keep a secret and consistent with their stories. All of the forensic evidence down to carbon dating of dust particles would need to be consistent, and you’d need to foresee decades of developments in archeological techniques which might uncover your plot. The moment your scam is uncovered your reputation is irreparably destroyed, you become a pariah and your professional life ends. Given that it seems wildly unlikely to be an outright scam, although anything is possible.
You would think that kind of thing would be such a strong disincentive that nobody would try it, but then again...
Andrew Wakefield: https://en.wikipedia.org/wiki/MMR_vaccine_controversy
That being said, it is extremely improbable.
Andrew Wakefield: https://en.wikipedia.org/wiki/MMR_vaccine_controversy
That being said, it is extremely improbable.
Another example from archaeology:
https://en.wikipedia.org/wiki/Japanese_Paleolithic_hoax
https://en.wikipedia.org/wiki/Japanese_Paleolithic_hoax
Another example: https://en.m.wikipedia.org/wiki/Piltdown_Man
Ooh, good point with Wakefield, what a piece of work! The harm he did will almost certainly outlive him, so I guess that’s a legacy?!
"Finding a human bone in the Nefud Desert—a windswept oval patch of sand dunes the size of Kentucky—is perhaps the world’s most impressive example of an unlikely find"
I wonder how you can test that a fossil wasn't just discovered elsewhere and moved to a convenient place, if the ground composition is sufficiently similar
I wonder how you can test that a fossil wasn't just discovered elsewhere and moved to a convenient place, if the ground composition is sufficiently similar
I'm not an expert in archeology but from my understanding, we can gain alot of information from bones that could lead such a finding.
For instance, carbon dating and analysing the ethnic origins of the skeleton could lead you to say that you have an Australian (Australoid) fossil from 20,000 years ago.
If you found that in Northern America that would raise serious questions about where exactly it was found and if it was moved since it doesn't fit within any of our current understandings of migration patterns.
For instance, carbon dating and analysing the ethnic origins of the skeleton could lead you to say that you have an Australian (Australoid) fossil from 20,000 years ago.
If you found that in Northern America that would raise serious questions about where exactly it was found and if it was moved since it doesn't fit within any of our current understandings of migration patterns.
Can't they do destructive testing of a part of the fossil using some isotope with a longer half life than carbon 14? It's described as being in a field of bones sticking out of sand so it's the only possible way it could have been accurately dated - no surrounding sedimentary rock formation to do additional testing upon.
They didn't use carbon-14.
"Groucutt and the rest of the team used a number of dating methods to confirm the likely age of the Al Wusta finger. For the finger itself and the tooth of an ancient hippopotamus found nearby, they applied U-series dating. Like radiocarbon dating, the method works by looking at radioactive decay in the preserved materials. The age of the sediments around the bones was calculated using optically stimulated luminescence—a technique that reveals the last time rocks and sand were exposed to sunlight."
"Groucutt and the rest of the team used a number of dating methods to confirm the likely age of the Al Wusta finger. For the finger itself and the tooth of an ancient hippopotamus found nearby, they applied U-series dating. Like radiocarbon dating, the method works by looking at radioactive decay in the preserved materials. The age of the sediments around the bones was calculated using optically stimulated luminescence—a technique that reveals the last time rocks and sand were exposed to sunlight."
Does this address the problem of knowing if the bones were moved?
A nearby hippo bone was also tested. It seems rather unlikely that a human bone and a hippo bone of similar age would have been stumbled across somewhere else compared to this site which appears to be a dried up body of water.
Um, why wouldn't it have been useful to describe it as being found in the original location, in that case? It'd still be noteworthy.
This seems likely as there are increasing findings of human activity that go much before 60,000 around the world.
One that recently comes to mind is a sight in Cambodia where there are traces of human activity dated around 71,000 years ago. (https://phnompenhpost.com/national-post-depth/peeling-back-l...)
What if the bone was left there? Say by a bird? Or another human. It's a single small hand bone. It feels fair to question how else it might have arrived at where it was found.
So much of paleontology is wild-ass guesses extrapolated out from miniscule, fragmentary evidence. In any other field, it'd be wildly irresponsible to generalize in such fashion on such slim evidence.
A bird probably wouldn't have carried it far, which would be evidence of human presence nearby.
If dropped by a human, then that would still be evidence of the presence of humans.
Unless you're suggesting that the bird or human buried the finger in the soil without creating any signs of the soil having been disturbed.
If dropped by a human, then that would still be evidence of the presence of humans.
Unless you're suggesting that the bird or human buried the finger in the soil without creating any signs of the soil having been disturbed.
It's worrying to see research into land migration hypothesis is itself becoming extremely difficult to confirm; I wonder whether the southern exit hypothesis (crossing red sea) or other water-route migrations would see new facts soon.
Could someone have moved it 45000 years ago as a joke like how Tesla launched a car for the aliens to scratch their heads in perpetuity?
They are not dating the bone, they are dating the mud around the bone. To be more precise, they are dating the last time the mud around the bone received sunlight. (And from the patterns in the mud they are sure that nobody dig a hole at midnight to put the bone there.)
They also dated the bone.
Well probably not as a joke, but it's within the realm of possibility that it was moved there at some point in the past. This is pure speculation of course, but perhaps it was identified as a sacred object and carried there by a traveller sometime within the last couple of thousand years. However the likelihood of that is probably quite slim.
That would leave signs of the soil having been disturbed.
"as a joke"
Religious rituals are just as likely, as well as being deposited with ani al droppings after becoming an unfortunate snack for some scavenger or carnivore. Also flood runoff, why not?
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or, "Remnants of Prehistoric Adam's Family Production Gives The Finger To Paleontologists"
Where's the rest of the skeleton?
This finding is only significant because of the age, but have we ever verified our dating techniques over 5k years? 10k years? What’s to say that the hot desert sun and strange weather patterns, radiation or whatever couldn’t skew the dating and mean this bone is just some traveller from a mere 1-2k years ago.
It seems further unlikely that such a bone from, 85k y/ago as they say, would be so close to the surface.
Ftn In mechanical engineering we don’t ever “trust” the calculations until they are thoroughly validated with ie strain gauges. And more often than not we discover our assumptions were wrong. So I suppose a similar thing applies here in dating science, except, it’s impossible to validate for another thousand centuries. It seems backwards to hinge all our science on it when (AFAICT) it hasn’t even been validated itself!