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But we find fossils of dinosaurs all the time. Wouldn’t tools and stuff also end up in the geological record.

JumpCrisscross 2y ago
> we find fossils of dinosaurs all the time “…for all the dinosaurs that ever lived, there are only a few thousand near-complete specimens, or equivalently only a handful of individual animals across thousands of taxa per 100,000 years. Given the rate of new discovery of taxa of this age, it is clear that species as short-lived as Homo sapiens (so far) might not be represented in the existing fossil record at all” [1]. > Wouldn’t tools and stuff also end up in the geological record Corrode, break down, subsume into the mantle, et cetera. [1] https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/silurian-hypothesis-would-it-be-possible-to-detect-an-industrial-civilization-in-the-geological-record/77818514AA6907750B8F4339F7C70EC6 https://www.cambridge.org/core/journals/international-journa...
- throwup238 2y ago
  I think that oversells just how rare fossils are. Complete skeletons are rare but the regions that are known for producing fossils are extremely productive, for lack of a better word. If you’re in California, you can go to Sharktooth Hill in Bakersfield to understand what that means. Million year old Megalodon teeth are plentiful and a few days digging is all but guaranteed to find several of them, among many other bones. The hard part is identifying the geological formations and excavating them while preserving context, which is impossible when its open to the public for digging. Once we’ve found the formations, it takes decades and decades because of a lack of funding and manpower (especially to assemble and research them). Complete skeletons are especially rare because we haven’t had the technology to reassemble bone correctly until recently with surface proteomic analysis.
  - JumpCrisscross 2y ago
    > the regions that are known for producing fossils are extremely productive, for lack of a better word Source that might quantify that in terms of frequency? > you can go to Sharktooth Hill in Bakersfield Or Scott’s Valley or Capitola. There are a lot. Now consider how many clams or trilobites existed across those hundreds of millions of years. Pushing back because I’ve never seen this prong of their hypothesis contested. Keep in mind that most oceanic crust formed less than 200 Mya [1]. (Continents are better, clocking in at Ga timescales [2].) [1] https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2007GC001743 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200... Figure 1 [2] http://www.lithosphere.info/papers/2006-Tecto-Art-TC1-small.pdf http://www.lithosphere.info/papers/2006-Tecto-Art-TC1-small.... Table 1
    - throwup238 2y ago
      I don’t know of any studies of the scale but there are millions of bones and fragments in museum storage that will never see the light of day because there’s no one to study them, and that’s just the bones people bothered to collect and save. Obviously thats out of trillions of animals and only a tiny fraction of animals get fossilized and plenty of species never left a record, but at the human scale, we have so many freaking fossils we have no idea what to do with them. We bring our kids out on field trips to dig for them and leave with dozens of bones per kid that are at least hundreds of thousands of year old, because no one bothers if they're <10My old otherwise. I’m not arguing that the fossil record is any more than a minuscule sliver of all animals that have ever lived, but there are still a lot of them and there’s no doubt human civilization is leaving its own behind that will be detectable millions of years from now.
      - JumpCrisscross 2y ago
        > we have so many freaking fossils Does that challenge that we only have fossils for “only a handful of individual animals across thousands of taxa per 100,000 years”? Less than 0.1% of species wind up in the fossil record [1]. (I’ve heard but can’t reliably source 5% for animals.) Most of those species existed far longer than we have. Hence why the astrophysicists who came up with the hypothesis ruled out fossils, much less fossils that would show evidence of industrial civilisation. > no doubt human civilization is leaving its own behind that will be detectable millions of years from now Sure, 2+ million, per the paper that sparked this. [1] https://www.bbc.com/future/article/20180215-how-does-fossilisation-happen https://www.bbc.com/future/article/20180215-how-does-fossili...
  - est31 2y ago
    Dinosaurs have also been around orders of magnitude longer than humans. Behaviourally modern humans have been around for 50k years, while Dinosaurs were dominant on this planet from the T-J to C-P extinction events, so approximately 140 million years. That's three orders of magnitude. Also, even though nowadays 95% of mammalian biomass is either humans or exists to serve human needs, we still will need a long period to catch up to the legacy of the dinosaurs.

> we find fossils of dinosaurs all the time “…for all the dinosaurs that ever lived, there are only a few thousand near-complete specimens, or equivalently only a handful of individual animals across thousands of taxa per 100,000 years. Given the rate of new discovery of taxa of this age, it is clear that species as short-lived as Homo sapiens (so far) might not be represented in the existing fossil record at all” [1]. > Wouldn’t tools and stuff also end up in the geological record Corrode, break down, subsume into the mantle, et cetera. [1] https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/silurian-hypothesis-would-it-be-possible-to-detect-an-industrial-civilization-in-the-geological-record/77818514AA6907750B8F4339F7C70EC6 https://www.cambridge.org/core/journals/international-journa...

throwup238 2y ago
I think that oversells just how rare fossils are. Complete skeletons are rare but the regions that are known for producing fossils are extremely productive, for lack of a better word. If you’re in California, you can go to Sharktooth Hill in Bakersfield to understand what that means. Million year old Megalodon teeth are plentiful and a few days digging is all but guaranteed to find several of them, among many other bones. The hard part is identifying the geological formations and excavating them while preserving context, which is impossible when its open to the public for digging. Once we’ve found the formations, it takes decades and decades because of a lack of funding and manpower (especially to assemble and research them). Complete skeletons are especially rare because we haven’t had the technology to reassemble bone correctly until recently with surface proteomic analysis.
- JumpCrisscross 2y ago
  > the regions that are known for producing fossils are extremely productive, for lack of a better word Source that might quantify that in terms of frequency? > you can go to Sharktooth Hill in Bakersfield Or Scott’s Valley or Capitola. There are a lot. Now consider how many clams or trilobites existed across those hundreds of millions of years. Pushing back because I’ve never seen this prong of their hypothesis contested. Keep in mind that most oceanic crust formed less than 200 Mya [1]. (Continents are better, clocking in at Ga timescales [2].) [1] https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2007GC001743 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200... Figure 1 [2] http://www.lithosphere.info/papers/2006-Tecto-Art-TC1-small.pdf http://www.lithosphere.info/papers/2006-Tecto-Art-TC1-small.... Table 1
  - throwup238 2y ago
    I don’t know of any studies of the scale but there are millions of bones and fragments in museum storage that will never see the light of day because there’s no one to study them, and that’s just the bones people bothered to collect and save. Obviously thats out of trillions of animals and only a tiny fraction of animals get fossilized and plenty of species never left a record, but at the human scale, we have so many freaking fossils we have no idea what to do with them. We bring our kids out on field trips to dig for them and leave with dozens of bones per kid that are at least hundreds of thousands of year old, because no one bothers if they're <10My old otherwise. I’m not arguing that the fossil record is any more than a minuscule sliver of all animals that have ever lived, but there are still a lot of them and there’s no doubt human civilization is leaving its own behind that will be detectable millions of years from now.
    - JumpCrisscross 2y ago
      > we have so many freaking fossils Does that challenge that we only have fossils for “only a handful of individual animals across thousands of taxa per 100,000 years”? Less than 0.1% of species wind up in the fossil record [1]. (I’ve heard but can’t reliably source 5% for animals.) Most of those species existed far longer than we have. Hence why the astrophysicists who came up with the hypothesis ruled out fossils, much less fossils that would show evidence of industrial civilisation. > no doubt human civilization is leaving its own behind that will be detectable millions of years from now Sure, 2+ million, per the paper that sparked this. [1] https://www.bbc.com/future/article/20180215-how-does-fossilisation-happen https://www.bbc.com/future/article/20180215-how-does-fossili...
- est31 2y ago
  Dinosaurs have also been around orders of magnitude longer than humans. Behaviourally modern humans have been around for 50k years, while Dinosaurs were dominant on this planet from the T-J to C-P extinction events, so approximately 140 million years. That's three orders of magnitude. Also, even though nowadays 95% of mammalian biomass is either humans or exists to serve human needs, we still will need a long period to catch up to the legacy of the dinosaurs.