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> The article further vindicates Graham Hancock's complaints of vicious mis-representation. His projections are certainly wrong in myriad details, but he is totally sincere in advancing them.

I’ll +1 some of this - the evidence is mounting that standing theories re. the end of the last ice age, impact hypothesis, development of civilization, at the least deserve another look and not quite so much dogma. More underwater archaeology is needed off the coasts, and under the Amazon and probably Sahara. These are all tough places to investigate but who knows, maybe we need to push our civilizational history back a few thousand years.

Graham really can’t clutch his pearls too much though. His early stuff was just kooky and he still has a tendency to weave way too much of the metaphysical and flat-out conjecture into his ideas. It turns academics off (putting it mildly), exactly the people who’s credibility and attention he craves. It’s tough for me to tell when Graham has actually done some interesting research and is calling out something real vs Graham when he’s nine oh-what-if-they? levels deep into conjecture.

If Graham would put his head down, eat a great big ice cream scoop of skepticism chocolate, and then go do investigative work and let the facts lead him - full stop - he’d probably make a ton more progress with his ideas than he has.

Hancock is equipped neither by training nor temperament to be a scientist. He does not pretend to be one. Trying, he would fail. Judging him as one is deeply silly. He calls himself a journalist. He is a storyteller, and invents engaging stories.

What he attempts is very different from science. He openly speculates about where the evidence might lead. His failure to understand some of the evidence, and what is possible, sometimes leads him to howlers. But remarkably often he has predicted finds that historians foolishly insisted were impossible.

His appeal is in actually engaging with evidence historians and archaeologists try to conceal or downplay. He takes us to actual sites, and shows us evidence historians refuse to discuss, or as often openly lie about. His speculations are fluff. But taking us around to see things, and inviting us to speculate along with him, is engaging in ways nothing allowed to scientists can.

Scientists could draw huge benefit from engaging with the evidence he exposes, instead of demonizing him. Their complaints fall flat because he is, simply, not a scientist, even a bad one, and should not be treated like one. He inspires with what might be, which is a good thing, and that he would do better with better help.

(Uniquely, Scientists Against Myths, on YT, does more engagement than anybody else, but in a way that is badly off-putting. They forget that they are addressing the audience, not their perceived myth-maker enemies.)

He would still be often wrong, but more interestingly wrong. And sometimes, still, he would turn out to be right. There is nothing wrong with that.

>People living in southeast Asia 70,000 years ago were certainly sailing out of sight of land, because they reached and colonized Australia. It beggars belief to suggest they did not also go to other places in equally easy reach, and then others from there.

My understanding is that those who reached Australia did not go further, because they forgot how to build ocean-worthy vessels.

There was nowhere further to go, unless you count New Zealand. We don't know if they reached New Zealand. But Australia/New Guinea/Tasmania (called Sahul) was plenty of territory, by itself.

The people who sailed to Australia were of a culture that could sail in any direction, and would have. You would need to come up with a reason for them not to.

And reaching Australia from Asia by island-hopping is much easier than reaching NZ from Australia.

Comet strike?

There's a theory that the Younger Dryas was caused by an impact of a bolide on a North American glacier, usually of one that fragmented considerably on entry.

There was certainly a bolide strike roughly coincident with the beginning of the 1300-year Younger Dryas cold spell.

Whether the strike caused the Younger Dryas cold spell is a matter of speculation. We can anyway be confident that the cold spell did not cause the bolide strike.

> There was certainly a bolide strike.

There was not certainly a bolide strike. No one has identified an unambiguous sign of such a strike; a purported impact crater was identified in Greenland a few years ago, but it is not yet confirmed as an impact crater, nor is it well-constrained to occur around the Younger Dryas. (There's apparently a paper suggesting that it's off a tad, maybe 50 million years too early).

The ice core record is unambiguous, corroborated by soil samples from literally dozens of sites as far away as Syria, South Africa, and southern Chile. South African lake sediment identifies an exact year.

The smoking gun is the layer of massively enriched platinum dust without the excess sulfur an eruption would emit, and melt spherules. Anyone doubting a bolide strike needs to account for it all in some other way, a tall order.

A crater would be convenient, but is not necessary: we know about airbursts now. E.g., there is no Tunguska crater. Demanding a crater is not scrupulous.

What's the citation for the ice core stuff? I found two papers that investigated this and neither found evidence to support the impact theory, so it seems ambiguous to me, but this isn't my field so obviously I might just be failing to find a more recent result.

If you wanna read em:

Paquay, François S., et al. “Absence of Geochemical Evidence for an Impact Event at the Bølling-Allerød/Younger Dryas Transition.” Proceedings of the National Academy of Sciences of the United States of America, vol. 106, no. 51, 2009, pp. 21505–10

Surovell, Todd A., et al. “An Independent Evaluation of the Younger Dryas Extraterrestrial Impact Hypothesis.” Proceedings of the National Academy of Sciences of the United States of America, vol. 106, no. 43, 2009, pp. 18155–58.

Update: Found (some?) ice core evidence, it is indeed more recent, but I'm hopelessly out of my wheelhouse at this point so I'll just cite it for anyone also interested and suggest that these more recent publications do seem pretty confident in their conclusion that the impact did happen. So it seems user moloch-hai is correct:

Petaev, Michail I., et al. “Large Pt Anomaly in the Greenland Ice Core Points to a Cataclysm at the Onset of Younger Dryas.” Proceedings of the National Academy of Sciences of the United States of America, vol. 110, no. 32, 2013, pp. 12917–20.

Pretty cool stuff, thanks for sharing and prompting me to learn more about it.

Those are both from 2009, ten years before the smoking gun cited.

They are studiously silent now. [Edit: Thank you for Petaev. I had not seen it.]

> Those are both from 2009, ten years before the smoking gun cited.

Just so you're aware, you haven't actually cited the study yet in this thread.

(Kjær, Kurt H., et al. "A large impact crater beneath Hiawatha Glacier in northwest Greenland." Science advances 4.11 (2018) is the citation, for future reference)

(FWIW, Kenny, Gavin G., et al. "A Late Paleocene age for Greenland’s Hiawatha impact structure." Science advances 8.10 (2022) disputes the age given for that impact crater.)

As already noted, any connection to Hiawatha crater was only ever conjecture. Evidence that Hiawatha was not coincident with the YDB obviously tells us nothing at all about YDB events.

A recent survey article is Sweatman,

The Younger Dryas impact hypothesis: Review of the impact evidence

https://www.sciencedirect.com/science/article/abs/pii/S00128...

The remaining controversy is how much the strike contributed to the Younger Dryas development and other coincident events, particularly extinctions. To me, it is ludicrous to blame those on Clovis people, or on a climate hiccup smaller than they had weathered easily many times before. Now that we know people had already been there for 10+ millennia, the sudden wipeout idea gets much sillier.

The idea that the strike triggered the YD is appealing, but the record shows several other such cooling periods with very similar profile and duration in the past 100ky. It seems unlikely they were all triggered by comet strikes. But they could have been: we now know our records of comet strikes are woefully incomplete, having detected a very recent one only by enormous effort.