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Someone recently applied paint AND it was thought the fossil was 280m years old. It does rather carry a pall over the idea we can accurately date anything, doe

Someone recently applied paint AND it was thought the fossil was 280m years old. It does rather carry a pall over the idea we can accurately date anything, doesn't it?

blueflow 3y ago
You date fossils from the strata they are found in.
- miniwark 3y ago
  But you also (partially) date strata from the fossils who are found in them...
  - lawlessone 3y ago
    >But you also (partially) date strata from the fossils who are found in them... And carbon dating. And decay of uranium into lead. They usually have multiple techniques that can be used together.
    - kadoban 3y ago
      Nit just because it's interesting (to me at least): carbon dating is never useful on things this old. The halflife of carbon-14 is so short that by about 50k years you're pushing it to about its limit. But yeah there's all kinds of decay chains and geology techniques used to date these things. It's a really cool mix of logical deduction and chemistry and cleverness.
      - dredmorbius 3y ago
        Building on this, the general concept is radiometric dating, which can rely on any of numerous decay chains, with half-lives ranging from decades to 100s of billions of years. Specific decay chains are effective clocks for differing lengths of time. Radiocarbon dating is often used on recent human or organic artefacts or remains, within the past 50,000 years or so as noted. It was uranium-lead decay which first demonstratively showed that the Earth was not "young", whether the few thousand years of theological textual analysis or the 30--300 million years that various geological estimates had suggested, but at least 1 billion years old, established by Ernest Rutherford in the early 20th centuries. The present value of 4.54 +/- 0.05 billion years was arrived at by the 1950s, based on the ratios of lead to uranium within zircon crystals, the latter of which cannot form in the presence of lead, and hence, any lead present necessarily being the result of radioactive decay. The measurement process also demonstrated the extent to which modern industrial activity was creating pervasive lead contamination virtually everywhere, largely the result of leaded gasoline, one of Thomas Midgley's lethal legacies. More generally, geochronology is based on numerous methods of which radiometric dating is but one, though a quite powerful one. <https://en.wikipedia.org/wiki/Radiometric_dating https://en.wikipedia.org/wiki/Radiometric_dating> <https://en.wikipedia.org/wiki/Age_of_Earth https://en.wikipedia.org/wiki/Age_of_Earth> <https://en.wikipedia.org/wiki/Geochronology https://en.wikipedia.org/wiki/Geochronology>
SEMW 3y ago
...No...? If someone puts paint on a 280 million year old rock, that doesn't change the age of the rock.
- a_gnostic 3y ago
  Earth rocks are about 4.54 ± 0.05 Billion years old. The atoms comprising those rocks are *about 13.787 ± 0.020 Billion years old.
  - gghffguhvc 3y ago
    Hydrogen and helium on earth would be 13.7 billion years old but many of the other atoms on earth are more like 4.6 billion years old.
    - shagie 3y ago
      https://en.wikipedia.org/wiki/Helium https://en.wikipedia.org/wiki/Helium > On Earth, it is relatively rare—5.2 ppm by volume in the atmosphere. Most terrestrial helium present today is created by the natural radioactive decay of heavy radioactive elements (thorium and uranium, although there are other examples), as the alpha particles emitted by such decays consist of helium-4 nuclei. This radiogenic helium is trapped with natural gas in concentrations as great as 7% by volume, from which it is extracted commercially by a low-temperature separation process called fractional distillation. Terrestrial helium is a non-renewable resource because once released into the atmosphere, it promptly escapes into space. Its supply is thought to be rapidly diminishing. However, some studies suggest that helium produced deep in the Earth by radioactive decay can collect in natural gas reserves in larger-than-expected quantities, in some cases having been released by volcanic activity.
  - lazide 3y ago
    The atoms themselves are far older, as they originated from some nuclear synthesis event in a star somewhere else (generally). Rocks on earth are rarely that old, as they’re composed from sedimentation (aka they get weathered then deposited), metamorphosed (compacted and modified by heat and pressure), cool from a lava flow (basalt, etc). [https://en.m.wikipedia.org/wiki/List_of_rock_types https://en.m.wikipedia.org/wiki/List_of_rock_types] Each of those forms/types changes fundamental properties of the rocks which allows for dating. Some rocks are literally only tens of years old, or even formed yesterday. Like basalt formed from lava from active volcanos.
seventytwo 3y ago
No… we can (relatively) accurately date things using many different methods. There’s no need to cast broad suspicion on scientific methods.
vanderZwan 3y ago
Eh, no, not really, because the article makes clear that this fossil has the rare combination of having been found before modern dating techniques existed, as well as having been treated extra carefully because of its "unique" status, and therefore avoiding some of those dating techniques until recently. > How could scientists have presumed the dark outline was carbonized soft tissue for so many decades? "This fossil was discovered in 1931 and back then fossils were treated very differently than today," said Rossi. "Application of paints, consolidates and lacquers on fossil bones was the norm, because that was the only way to protect the specimens from further deterioration. It was also sometimes to embellish specimens by making them sleek and shiny. Unfortunately, in the case of Tridentinosaurus, the mechanical preparation did most of the damage and then the application of a black paint created the illusion of a lizard-like animal impression on the surface of the rock." If anything, I am constantly blown away by how accurately we actually can date things. For example, thanks to dendrochronology[0] we can now often accurately date the exact year prehistoric wooden constructions like buildings or bridges were made, up to almost 14,000 years into the past! And that range will only increase. [0] https://en.wikipedia.org/wiki/Dendrochronology https://en.wikipedia.org/wiki/Dendrochronology

Someone recently applied paint AND it was thought the fossil was 280m years old. It does rather carry a pall over the idea we can accurately date anything, doesn't it?

blueflow 3y ago

You date fossils from the strata they are found in.

miniwark 3y ago
But you also (partially) date strata from the fossils who are found in them...
- lawlessone 3y ago
  >But you also (partially) date strata from the fossils who are found in them... And carbon dating. And decay of uranium into lead. They usually have multiple techniques that can be used together.
  - kadoban 3y ago
    Nit just because it's interesting (to me at least): carbon dating is never useful on things this old. The halflife of carbon-14 is so short that by about 50k years you're pushing it to about its limit. But yeah there's all kinds of decay chains and geology techniques used to date these things. It's a really cool mix of logical deduction and chemistry and cleverness.
    - dredmorbius 3y ago
      Building on this, the general concept is radiometric dating, which can rely on any of numerous decay chains, with half-lives ranging from decades to 100s of billions of years. Specific decay chains are effective clocks for differing lengths of time. Radiocarbon dating is often used on recent human or organic artefacts or remains, within the past 50,000 years or so as noted. It was uranium-lead decay which first demonstratively showed that the Earth was not "young", whether the few thousand years of theological textual analysis or the 30--300 million years that various geological estimates had suggested, but at least 1 billion years old, established by Ernest Rutherford in the early 20th centuries. The present value of 4.54 +/- 0.05 billion years was arrived at by the 1950s, based on the ratios of lead to uranium within zircon crystals, the latter of which cannot form in the presence of lead, and hence, any lead present necessarily being the result of radioactive decay. The measurement process also demonstrated the extent to which modern industrial activity was creating pervasive lead contamination virtually everywhere, largely the result of leaded gasoline, one of Thomas Midgley's lethal legacies. More generally, geochronology is based on numerous methods of which radiometric dating is but one, though a quite powerful one. <https://en.wikipedia.org/wiki/Radiometric_dating https://en.wikipedia.org/wiki/Radiometric_dating> <https://en.wikipedia.org/wiki/Age_of_Earth https://en.wikipedia.org/wiki/Age_of_Earth> <https://en.wikipedia.org/wiki/Geochronology https://en.wikipedia.org/wiki/Geochronology>

SEMW 3y ago

...No...? If someone puts paint on a 280 million year old rock, that doesn't change the age of the rock.

a_gnostic 3y ago
Earth rocks are about 4.54 ± 0.05 Billion years old. The atoms comprising those rocks are *about 13.787 ± 0.020 Billion years old.
- gghffguhvc 3y ago
  Hydrogen and helium on earth would be 13.7 billion years old but many of the other atoms on earth are more like 4.6 billion years old.
  - shagie 3y ago
    https://en.wikipedia.org/wiki/Helium https://en.wikipedia.org/wiki/Helium > On Earth, it is relatively rare—5.2 ppm by volume in the atmosphere. Most terrestrial helium present today is created by the natural radioactive decay of heavy radioactive elements (thorium and uranium, although there are other examples), as the alpha particles emitted by such decays consist of helium-4 nuclei. This radiogenic helium is trapped with natural gas in concentrations as great as 7% by volume, from which it is extracted commercially by a low-temperature separation process called fractional distillation. Terrestrial helium is a non-renewable resource because once released into the atmosphere, it promptly escapes into space. Its supply is thought to be rapidly diminishing. However, some studies suggest that helium produced deep in the Earth by radioactive decay can collect in natural gas reserves in larger-than-expected quantities, in some cases having been released by volcanic activity.
- lazide 3y ago
  The atoms themselves are far older, as they originated from some nuclear synthesis event in a star somewhere else (generally). Rocks on earth are rarely that old, as they’re composed from sedimentation (aka they get weathered then deposited), metamorphosed (compacted and modified by heat and pressure), cool from a lava flow (basalt, etc). [https://en.m.wikipedia.org/wiki/List_of_rock_types https://en.m.wikipedia.org/wiki/List_of_rock_types] Each of those forms/types changes fundamental properties of the rocks which allows for dating. Some rocks are literally only tens of years old, or even formed yesterday. Like basalt formed from lava from active volcanos.

seventytwo 3y ago

No… we can (relatively) accurately date things using many different methods. There’s no need to cast broad suspicion on scientific methods.

vanderZwan 3y ago

Eh, no, not really, because the article makes clear that this fossil has the rare combination of having been found before modern dating techniques existed, as well as having been treated extra carefully because of its "unique" status, and therefore avoiding some of those dating techniques until recently. > How could scientists have presumed the dark outline was carbonized soft tissue for so many decades? "This fossil was discovered in 1931 and back then fossils were treated very differently than today," said Rossi. "Application of paints, consolidates and lacquers on fossil bones was the norm, because that was the only way to protect the specimens from further deterioration. It was also sometimes to embellish specimens by making them sleek and shiny. Unfortunately, in the case of Tridentinosaurus, the mechanical preparation did most of the damage and then the application of a black paint created the illusion of a lizard-like animal impression on the surface of the rock." If anything, I am constantly blown away by how accurately we actually can date things. For example, thanks to dendrochronology[0] we can now often accurately date the exact year prehistoric wooden constructions like buildings or bridges were made, up to almost 14,000 years into the past! And that range will only increase. [0] https://en.wikipedia.org/wiki/Dendrochronology https://en.wikipedia.org/wiki/Dendrochronology