Sweatman is actually not an archaeologist, and this whole concept he's been pushing for around a decade is actually dead wrong. It's incredible that this actually got published in a legitimate journal with an archaeological focus.
"The comet strike ushered in a 1,200-year ice age and led to the extinction of many large animals, Dr. Sweatman said. For humans, the comet probably also led to differences in lifestyle and agriculture that helped usher in the rise of civilization as we know it."
I thought the Americas' megafauna died after the ice age, not because of it?
however, it seems obvious that a widespread glaciation would have caused some extinctions, and there was a long tail of megafauna extinctions that extended long after the younger dryas. glyptodonts like https://en.wikipedia.org/wiki/Doedicurus apparently didn't become extinct until only 8000 years ago, and the wrangel island mammoths didn't become extinct until only 4000 years ago
jumploops 154 days ago [-]
Could both statements not be true?
The ice age may have encouraged humans to hunt more mammals than previously required.
cryptonector 153 days ago [-]
This is after the "ice age", meaning after the glacial period. The Younger Dryas was a period during the current inter-glacial where temperatures went down a great deal for a while -- a mini ice age within an inter-glacial period.
jmclnx 154 days ago [-]
>I thought the Americas' megafauna died after the ice age, not because of it?
There was a article that had "proof" that megafauna extinction was a result of Humans moving into that area. I think I saw it here in NH.
To me that is the theory I agree with.
vivekd 153 days ago [-]
I think it's a theory that should be regarded with suspicion. It too neatly aligns with modern world views and environmental concerns. That's not to say it's false, it may turn out to be true. Just as should tread carefully with it recognizing the social bias supporting it
Vecr 153 days ago [-]
There's probably social bias against it too, to the extent that it already means Australians burned down and killed everything, this would just be transferring that to other places.
aport 154 days ago [-]
You're correct, the comet theory has been debunked for years at this point.
torlok 154 days ago [-]
Can't wait to hear what archaeologists have to day about this interpretation. This is a fun topic to speculate about.
Meanwhile, in case anybody's interested, the Younger Dryas hypothesis is controversial, not widely accepted by the experts, and dr Sweatman appears to be a Chemical Engineer, not an Archeologist. Not that it discredits his findings, of course.
kragen 154 days ago [-]
to disambiguate, it is not at all controversial that the younger dryas was a thousand-year-long ice age in the northern hemisphere at the relevant time; that is universally accepted by the experts. what is 'controversial and not widely accepted by relevant experts' is the comet impact hypothesis which the nyt presents as an accepted fact: https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesi...
tivert 153 days ago [-]
> what is 'controversial and not widely accepted by relevant experts' is the comet impact hypothesis which the nyt presents as an accepted fact
Careful there. If people start questioning the NYT's reporting, they may start believing things like voting machines are unreliable and various other ideas pushed by Republicans.
debacle 154 days ago [-]
I haven't researched, but I watch the guys on Rogan who talk about Younger Dryas. What are the arguments for/against?
taejavu 154 days ago [-]
Sounds like you might benefit from doing some research
153 days ago [-]
mhuffman 153 days ago [-]
What better places do you recommend for research links? HN is known for being full of experts that might give high quality pointers to pro/con arguments.
mathgorges 153 days ago [-]
My general strategy is to find a community where $domainExperts hang out and figure out how they talk about $interestingThing, then refine my search from there using progressively more professional lingo.
They are entertainers on an entertaining platform, and the quality went way down the drain in the last 5 years. It's like watching someone slowly developing dementia
For those interested in exploring this topic in much more scientific detail than the NYTimes dares to try, his observations, interpretations and counter-arguments - going back many years - are available on his YTube channel here:
> Although Dr. Sweatman has long researched the symbols at the ancient site in Turkey, this recent breakthrough came in the form of a tip when someone emailed him that the V-shaped symbols on the pillar could be interpreted as markings of the lunar cycle.
They didn't want to be coauthor?
burkaman 154 days ago [-]
I guess not, but they are mentioned in the acknowledgements and references of the paper.
> In Section 8.2, text written in italic font expresses ideas originally communicated by Dr John Gordon (Gordon 2021).
I cannot see where the NYT article you link is calling the Young Dryas Impact Hypothesis (YDiH) racist. The article reports a claim of racism that was made by the Society for American Archeology but this claim was about the idea of an advanced ice-age civilisation, not the YDIH. From your link:
The society also argued that Hancock’s idea of an advanced ice-age civilization echoed and promoted “dangerous racist thinking.” (Hancock posted a detailed denial of these claims on his website.)
I can't find where the NYT article is calling the YDIH "conspiracist". The article reports the opinions of others who seem to think there is something conspiratorial to it, but the article itself does not directly claim that it is conspiratorial.
reedf1 154 days ago [-]
Careful analysis must be taken to avoid falling victim to the look-elsewhere effect. It is easy to find any numerical relationship you want with motivated reasoning.
throwaway290 154 days ago [-]
TLDR YDIH, if you watched Ancient Apocalypse this is what Gobekli Tepe episode was about. I thought it's debunked.
cryptonector 153 days ago [-]
The evidence for the YDIH is quite strong. But as usual science only makes progress one obituary at a time.
Science is not an exercise in accepting a scientist's say-so, dammit. It's an exercise in producing and testing hypothesis. For sciences that study the past it's harder to test because you can't build a test, but you can still check that a hypothesis is consistent with all the data available so far and any future new finds about the past.
In particular I find very compelling the theory that the YDIH hit the laurentide ice sheet over Michigan, sending huge ice boulders out that created the Carolina bays and essentially did great damage, but with water ice, thus leaving very little direct physical evidence -- no craters (apart from the Carolina bays), no rocks out of place, no layer of material from the impactor (because it was a comet rather than an asteroid).
Before sonar evidence showed that the continents must move, geologists would say that the tectonics theory was debunked (using whatever the appropriate term was then). Well here we are now saying the exact opposite.
The only thing we can say with certainty right now is that we don't have consensus as to the cause of the Younger Dryas at this time. To say that the YDIH is debunked is not true and not helpful.
YeGoblynQueenne 153 days ago [-]
>> In particular I find very compelling the theory that the YDIH hit the laurentide ice sheet over Michigan, sending huge ice boulders out that created the Carolina bays and essentially did great damage, but with water ice, thus leaving very little direct physical evidence -- no craters (apart from the Carolina bays), no rocks out of place, no layer of material from the impactor (because it was a comet rather than an asteroid).
In that case, how do can we tell that's what happened?
cryptonector 153 days ago [-]
Antonio Zamora is a scientist studying this who writes papers and posts videos on YouTube at https://www.youtube.com/@Antonio_Zamora and he does a good job of showing how the Carolina bays point towards the impact location, and what not. I'm not going to summarize it all here, but the point is that there is some, and perhaps enough evidence to go on.
jschveibinz 153 days ago [-]
"Science is not an exercise in accepting a scientist's say-so, dammit."
May your words echo in the hallways of this forum!
cryptonector 153 days ago [-]
Don't hold your breath. HN is full of people with credentials, and people with credentials tend to push credentialism, and that means deferring to the experts on other fields so that others will defer to one in one's field of expertise.
Mike Shapiro at Sun was fond of telling us that "we're not specialists -- we're generalists who can specialize as needed". I think that is a good attitude in general. It doesn't mean we get to weigh in on things we know nothing about, but it does mean we get to do critical thinking and that we can self-educate in order to form opinions when necessary.
wkearney99 151 days ago [-]
And sensibility to recognize when having (let alone voicing) an opinion isn't necessary.
throwaway290 153 days ago [-]
OK good to know.
This is caused by comet remains through which Earth goes twice a year, right? If astronomy data supports "Earth totally could get hit by a chunk from it" that's also a step. Are future threats from these comet chunks trackable by NASA?
maxbond 152 days ago [-]
What do you find disatisfactory about the conventional explanation that the Carolina bays are thermokarsts?
On a smell test level, here's a picture of a thermokarsts:
Things aren't identical just because they look alike, but again on a smell test level, it doesn't immediately strike me as implausible.
I'm certainly no expert on impact craters but that doesn't really look like a field of impact craters to me. I've never seen a photo of a field of oblate impact craters. In the LIDAR you can see many of them overlap. That would suggest to me that what formed these ovals happened many times, rather than all at once.
If you think about it, the way you get an oblate crater is to hit at an extreme angle, right? But if was an airburst, then the debris would be going down. So it should make circular craters.
Maybe it's an airburst just off the ground, a few hundred feet up or something. That way it's close enough to spray the ground at an extreme angle. But then the Carolina bays would be very close to the epicenter. So we should see some rotation among the "craters". But they're parallel. Which would mean, if they were craters, that the blast was very far away. (In which case, they would have had time to come down in parabolic arcs, and we're back to circular craters.)
If it wasn't an airburst, then it was a direct hit a mere 13k years ago. That's young enough that we should be able to find the crater. I've seen supervolcano caldera much older than that, I wouldn't imagine a crater would erode any faster.
> To say that the YDIH is debunked is not true and not helpful.
I dunno. This isn't a scientific observation, but there's something fishy with this hypothesis. It's being popularized by conspiracy theorists, and the Comet Research Group, some of it's proponents, were busted for faking evidence. The theory posits something really attention grabbing and dramatic, but it's also very speculative and didn't originate in physical evidence.
Meanwhile the alternative explanation that the AMOC was choked out by freshwater melting off the glaciers is very tidy, there's ample physical evidence for it, and it doesn't need to bring in an unlikely and external element like a comet. This explanation amounts to, "what we know was happening at the time kept happening until that forced the environment to change, through a well established mechanism we can continue to make physical observations of today." Contrast that with, "we're going to look at a time the environment changed, and back out an explanation of why that might have happened."
This just feels too convenient for me. This seems to be at least as much a vehicle for people like Hancock to claim their hypothesis - which just so happens to be a very cool and engaging story - isn't getting it's due from the scientific establishment, as it is a serious scientific endeavor to understand what happened in the Younger Dryas.
throwaway290 152 days ago [-]
CRG has a sus vibe indeed. It'd suck if it turns out true but our civilization is wiped out by another comet chunk because every good scientist who had the same idea just didn't want to hang out with that bunch.
cryptonector 152 days ago [-]
A civilization as advanced as ours would have to have bootstrapped via coal mining and burning like we did, and that would leave evidence in the CO2 records in the ice cores. There does not seem to be any evidence of such an advanced civilization in the ice cores, unless it wasn't remotely global in scope. There could have been less advanced (but still advanced) not-global-in-scope civilizations that we don't yet know about, but I don't see the link to the Carolina bays, unless it's to say that the same event wiped them out, but so what, I'm interested in the Carolina bays and their cause, and much less interested in speculation about advanced civilizations.
throwaway290 152 days ago [-]
What are you talking about? Comet research groups in past advanced civilizations? I'm confused. I was taking about our civilization and future.
cryptonector 152 days ago [-]
I thought you were referring to Hancock et. al. Keep in mind I know nothing about "CRG".
throwaway290 152 days ago [-]
I don't know anything about CRG except what I saw in Wikipedia, something about faked evidence and all that.
cryptonector 152 days ago [-]
> What do you find disatisfactory about the conventional explanation that the Carolina bays are thermokarsts?
For one, the bays don't look like thermokarsts, and for another the bays look like they "aim" at the impact sites, and they seem to form perimeters centered on the impact sites. That's highly suggestive.
> This isn't a scientific observation, but there's something fishy with this hypothesis. It's being popularized by conspiracy theorists, and the Comet Research Group, some of it's proponents, were busted for faking evidence.
I've no idea who they are. None. Is Zamora one of them? Can you tell me more about them? Everything I've seen is that he is very careful in what he says, and I've seen nothing from him about advanced civilizations.
> Meanwhile the alternative explanation that the AMOC was choked out by freshwater melting off the glaciers is very tidy
I agree with this. But that doesn't explain the Carolina bays, and the two things can have happened close enough in time, possibly for the same root reasons (impacts).
maxbond 152 days ago [-]
> For one, the bays don't look like thermokarsts
But they also don't look like craters? They don't look so dissimilar from thermokarsts, but craters really as a rule are circular.
> the bays look like they "aim" at the impact sites
Hey I'm just curious, did you look at the photos I posted? I know I wrote quite a bit, did you see where I raised questions about this specifically?
See this section from the Wiki article on the Carolina bays:
> Modern thermokarst lakes are common today around Barrow (Alaska), and the long axes of these lakes are oblique to the prevailing wind direction.
Are they "aiming at the impact site" or are they "oblique to the direction of the prevailing winds?" They look parallel to me. Wind is parallel in a local area. Shot from a nearby airburst is radial, and very much not parallel. Shot from a faraway airburst might be parallel, but you won't be able to tell because it'll produce circular craters, which isn't what we have.
> Can you tell me more about them?
Only what's in the YDIH Wikipedia article.
> [P]ossibly for the same root reasons (impacts).
I mean, we know about a different phenomenon that was going on that has a tendency to form lakes and pour huge amounts of freshwater into the oceans, right? Do we really have to assert that this comet exists in order to arrive at a plausible explanation? If not, then why are we bringing in the comet?
torlok 154 days ago [-]
It's a widely criticised hypothesis, because it doesn't fit the geological record. It's mostly propped up by interpretations like these.
findthewords 154 days ago [-]
Data is incomplete. It is difficult to definitively "debunk" or "prove" as long as crucial information is missing. Humans use imagination to fill in the gaps, which is wonderful.
cryptonector 153 days ago [-]
> Humans use imagination to fill in the gaps, which is wonderful.
And scientists (humans) "use imagination to fill in the gaps" in ways that can be put to the test, "which is wonderful".
154 days ago [-]
throwawaycar 153 days ago [-]
[dead]
Rendered at 04:13:48 GMT+0000 (Coordinated Universal Time) with Vercel.
I recommend reading this breakdown of why he's wrong from 2019: https://skepticink.com/lateraltruth/2019/01/25/martin-sweatm...
And a great spoof of his work showcasing the numerous logical fallacies in his reasoning: https://skepticink.com/lateraltruth/2018/12/07/decoding-loon...
I thought the Americas' megafauna died after the ice age, not because of it?
https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesi... discusses the comet impact hypothesis, which it describes as 'controversial and not widely accepted by relevant experts'
also note from https://en.wikipedia.org/wiki/Younger_Dryas that the younger dryas didn't happen in south america, which is where the largest extinction of american megafauna happened; instead south america had the milder and earlier https://en.wikipedia.org/wiki/Antarctic_Cold_Reversal
however, it seems obvious that a widespread glaciation would have caused some extinctions, and there was a long tail of megafauna extinctions that extended long after the younger dryas. glyptodonts like https://en.wikipedia.org/wiki/Doedicurus apparently didn't become extinct until only 8000 years ago, and the wrangel island mammoths didn't become extinct until only 4000 years ago
The ice age may have encouraged humans to hunt more mammals than previously required.
There was a article that had "proof" that megafauna extinction was a result of Humans moving into that area. I think I saw it here in NH.
To me that is the theory I agree with.
Meanwhile, in case anybody's interested, the Younger Dryas hypothesis is controversial, not widely accepted by the experts, and dr Sweatman appears to be a Chemical Engineer, not an Archeologist. Not that it discredits his findings, of course.
Careful there. If people start questioning the NYT's reporting, they may start believing things like voting machines are unreliable and various other ideas pushed by Republicans.
Here's an example of what my first query for this topic might be: https://kagi.com/search?q=site%3Areddit.com%2Fr%2Faskhistori...
They are entertainers on an entertaining platform, and the quality went way down the drain in the last 5 years. It's like watching someone slowly developing dementia
Between this dude: https://www.youtube.com/watch?v=GQ27ZtInsmo and Peterson I would advise you to look for new sources lmao
https://www.youtube.com/channel/UCx11KXwumf5w8J-GdBGKNVA/vid...
https://www.telegraph.co.uk/science/2017/04/21/ancient-stone...
https://www.maajournal.com/index.php/maa/article/view/686
They didn't want to be coauthor?
> In Section 8.2, text written in italic font expresses ideas originally communicated by Dr John Gordon (Gordon 2021).
Also on the author's blog: https://martinsweatman.blogspot.com/2024/06/lunisolar-calend...
Not sure who John Gordon is, and that's got to be an incredibly common name even among doctors.
Sandals also look identical from how they looked thousands of years ago. It’s not like human anatomy is different now than it was.
The society also argued that Hancock’s idea of an advanced ice-age civilization echoed and promoted “dangerous racist thinking.” (Hancock posted a detailed denial of these claims on his website.)
I can't find where the NYT article is calling the YDIH "conspiracist". The article reports the opinions of others who seem to think there is something conspiratorial to it, but the article itself does not directly claim that it is conspiratorial.
Science is not an exercise in accepting a scientist's say-so, dammit. It's an exercise in producing and testing hypothesis. For sciences that study the past it's harder to test because you can't build a test, but you can still check that a hypothesis is consistent with all the data available so far and any future new finds about the past.
In particular I find very compelling the theory that the YDIH hit the laurentide ice sheet over Michigan, sending huge ice boulders out that created the Carolina bays and essentially did great damage, but with water ice, thus leaving very little direct physical evidence -- no craters (apart from the Carolina bays), no rocks out of place, no layer of material from the impactor (because it was a comet rather than an asteroid).
Before sonar evidence showed that the continents must move, geologists would say that the tectonics theory was debunked (using whatever the appropriate term was then). Well here we are now saying the exact opposite.
The only thing we can say with certainty right now is that we don't have consensus as to the cause of the Younger Dryas at this time. To say that the YDIH is debunked is not true and not helpful.
In that case, how do can we tell that's what happened?
May your words echo in the hallways of this forum!
Mike Shapiro at Sun was fond of telling us that "we're not specialists -- we're generalists who can specialize as needed". I think that is a good attitude in general. It doesn't mean we get to weigh in on things we know nothing about, but it does mean we get to do critical thinking and that we can self-educate in order to form opinions when necessary.
This is caused by comet remains through which Earth goes twice a year, right? If astronomy data supports "Earth totally could get hit by a chunk from it" that's also a step. Are future threats from these comet chunks trackable by NASA?
On a smell test level, here's a picture of a thermokarsts:
https://upload.wikimedia.org/wikipedia/commons/7/73/Permafro...
And here's some pictures of the Carolina bays:
https://lh3.googleusercontent.com/-RzXM7ywZkS8/WKW0zLlhU4I/A...
https://en.m.wikipedia.org/wiki/Carolina_bays#/media/File%3A...
Things aren't identical just because they look alike, but again on a smell test level, it doesn't immediately strike me as implausible.
I'm certainly no expert on impact craters but that doesn't really look like a field of impact craters to me. I've never seen a photo of a field of oblate impact craters. In the LIDAR you can see many of them overlap. That would suggest to me that what formed these ovals happened many times, rather than all at once.
If you think about it, the way you get an oblate crater is to hit at an extreme angle, right? But if was an airburst, then the debris would be going down. So it should make circular craters.
Maybe it's an airburst just off the ground, a few hundred feet up or something. That way it's close enough to spray the ground at an extreme angle. But then the Carolina bays would be very close to the epicenter. So we should see some rotation among the "craters". But they're parallel. Which would mean, if they were craters, that the blast was very far away. (In which case, they would have had time to come down in parabolic arcs, and we're back to circular craters.)
If it wasn't an airburst, then it was a direct hit a mere 13k years ago. That's young enough that we should be able to find the crater. I've seen supervolcano caldera much older than that, I wouldn't imagine a crater would erode any faster.
> To say that the YDIH is debunked is not true and not helpful.
I dunno. This isn't a scientific observation, but there's something fishy with this hypothesis. It's being popularized by conspiracy theorists, and the Comet Research Group, some of it's proponents, were busted for faking evidence. The theory posits something really attention grabbing and dramatic, but it's also very speculative and didn't originate in physical evidence.
Meanwhile the alternative explanation that the AMOC was choked out by freshwater melting off the glaciers is very tidy, there's ample physical evidence for it, and it doesn't need to bring in an unlikely and external element like a comet. This explanation amounts to, "what we know was happening at the time kept happening until that forced the environment to change, through a well established mechanism we can continue to make physical observations of today." Contrast that with, "we're going to look at a time the environment changed, and back out an explanation of why that might have happened."
This just feels too convenient for me. This seems to be at least as much a vehicle for people like Hancock to claim their hypothesis - which just so happens to be a very cool and engaging story - isn't getting it's due from the scientific establishment, as it is a serious scientific endeavor to understand what happened in the Younger Dryas.
For one, the bays don't look like thermokarsts, and for another the bays look like they "aim" at the impact sites, and they seem to form perimeters centered on the impact sites. That's highly suggestive.
> This isn't a scientific observation, but there's something fishy with this hypothesis. It's being popularized by conspiracy theorists, and the Comet Research Group, some of it's proponents, were busted for faking evidence.
I've no idea who they are. None. Is Zamora one of them? Can you tell me more about them? Everything I've seen is that he is very careful in what he says, and I've seen nothing from him about advanced civilizations.
> Meanwhile the alternative explanation that the AMOC was choked out by freshwater melting off the glaciers is very tidy
I agree with this. But that doesn't explain the Carolina bays, and the two things can have happened close enough in time, possibly for the same root reasons (impacts).
But they also don't look like craters? They don't look so dissimilar from thermokarsts, but craters really as a rule are circular.
> the bays look like they "aim" at the impact sites
Hey I'm just curious, did you look at the photos I posted? I know I wrote quite a bit, did you see where I raised questions about this specifically?
See this section from the Wiki article on the Carolina bays:
> Modern thermokarst lakes are common today around Barrow (Alaska), and the long axes of these lakes are oblique to the prevailing wind direction.
Are they "aiming at the impact site" or are they "oblique to the direction of the prevailing winds?" They look parallel to me. Wind is parallel in a local area. Shot from a nearby airburst is radial, and very much not parallel. Shot from a faraway airburst might be parallel, but you won't be able to tell because it'll produce circular craters, which isn't what we have.
> Can you tell me more about them?
Only what's in the YDIH Wikipedia article.
> [P]ossibly for the same root reasons (impacts).
I mean, we know about a different phenomenon that was going on that has a tendency to form lakes and pour huge amounts of freshwater into the oceans, right? Do we really have to assert that this comet exists in order to arrive at a plausible explanation? If not, then why are we bringing in the comet?
And scientists (humans) "use imagination to fill in the gaps" in ways that can be put to the test, "which is wonderful".