A Sunken Bridge the Size of a Continent | Hacker News Reader

A Sunken Bridge the Size of a Continent

hakaimagazine.com

113 pointsjmadsen33 comments

I can't believe there is only one (other) top-level comment in this thread, and it's basically anti-science. It doesn't matter what you "subscribe" to, what matters are theories backed by scientifically collected data.

Is history generally considered a science? It would be weird to me for someone to use the scientific method to show that even Abraham Lincoln existed.

That's not to say that history isn't a form of knowledge. There's more to knowledge than science.

That's because there's a wealth of documentary evidence showing the Lincoln existed within the past 200 years.

Imagine if you were 10,000 years in the future. The United States has ceased to exist, and many of our monuments are buried in mud and rubble. The paper artifacts have mostly rotted away, or they lie buried in some preserving medium. No first-hand accounts remain from the period. One day, a team uncovers a partial statue of a seated man with a great beard. Was he a god, or an emperor of the land? How could they prove either stance without applying scientific techniques, gathering evidence from the remains of the surrounding buildings and analyzing it?

Archeology may not be a hard science, but it is an empirical science.

I love archaeology. I love evolutionary science. I love anthropology.

I'm not replying to you directly here. I have a concern about this thread. I felt this was the best place to put it.

Your use of the word "empirical" here may be accurate yet misleading.

Some sciences work with hard data, falsifiable hypothesis, repoducibility, and so forth. In these we can construct mathematical models which eventually we trust explicitly. (Note that in most cases these are not explanatory models, simply sufficient ones.)

Some sciences work with simple observation and correlation, with lots of imaginative community input in place to suppose causation. We can use mathematical models here as well, but there's a huge degree of noise here.

I have no problem with a forum participant coming up with their own speculation. If folks don't like it they can ignore it. Perhaps one day evidence turns up which validates that speculation.

We don't shut down those folks by calling them anti-science. Hell, give these people a book contract. The more imaginative narratives you can create from existing data, the more the scientific community at large will expand what they consider to be the world of alternatives to consider.

What I'm seeing a lot of lately is taking anything with the label "science" on it and telling laymen that they have no business bullshitting in this area. This is not in the best interest of either science or the academy.

ADD: I've seen the flip side of this as well, where really good scientists come up with the most wondrous and dramatic narratives about things where the evidence is thin. That's cool, but many of these folks will use the term "science" as a way of pumping up their speculative fiction. Stringing together a series of what most experts believe is likely while adding your own color commentary is not science. It's entertaining as hell and I love reading it. But it ain't science.

"We don't shut down those folks by calling them anti-science. Hell, give these people a book contract."

Don't you think there are already enough books out there based on pseudo-science that confuse and take advantage of the general public?

"What I'm seeing a lot of lately is taking anything with the label "science" on it and telling laymen that they have no business bullshitting in this area."

What if they don't even realize that they are bullshitting in the first place? The other day I was debating AGW (as I do) and my opponent, in response to my constant citing of work and my constant demand that he do the same, actually asked me why I didn't have any "facts from my head".

I do see your point, but when I see people unable to tell the difference between empirical data and an opinion, I think it might give "magical thinkers" or the "anti-science crowd" or whatever label they should have too much credit.

That topic is especially tough because of the highly-politicized nature of the topic.

Don't you think there are already enough books out there based on pseudo-science that confuse and take advantage of the general public?

No, I do not. Although I completely understand and agree with you that it creates a very bad environment for reasoned discussion. We've reached the point where anybody with any opinion at all can google around a bit and come up with pieces of data and nit-picks which lets them construct their own narrative -- regardless of whether it holds water or is self-consistent or not. There are a lot of "Google geniuses" out there, sadly.

AGW is not just one debate, but several. That's because it's not an argument around a closed system where one variable changes and we see clear causation. It's a series of arguments about many changes, the results of those changes, and the economic/future impact of those results over several decades.

Dude. That's a ton of stuff to try to pin down no matter who is in the debate. There are dozens, perhaps hundreds of complex systems involved. It's far too easy to pick and choose which of these you'd like to argue. It's probably the most complex (and whacked) public debate we have. I don't see physicists and the general public arguing about WIMPs, but everybody feels that they can take part equally in this discussion because some part of it may touch on their experiences, expertise, or political opinion.

The only good news I have is that there are only a few topics like that.

Valid points. IMO, pushing critical thinking is the best way to combat those issues. It wouldn't end silly ideological debates of course, but at least the discussions would perhaps be a little less "mindless".

As far as my AGW debate anecdote, all I did was ask for his sources (he claimed the planet had not warmed since 98...a position I didn't know anyone actually took) and he never did come up with anything. (besides telling me to "do my own research" on youtube...if that counts as a source, lol) I know that the AGW debate has a ton of facets, but this guy was just some low hanging fruit I guess. :)

Things have fallen off a bit since the late 90's... not that I'm AGW, I would posit that man may not be a huge influence and that it's likely not as big of an emergency in general as overall pollution and even population control probably are. Alarmist, reactionary legislation rarely does what it is intended to do, and to be honest, I think it detracts from the issue overall.

I happen to feel it's been globally warming since the last ice age, and that it seems to be a cyclical event, are we speeding up the next ice age, and what will seeing another 3-4 degree rise in temperatures in the next dozen or more decades change. And how much of that is actually of human/unnatural cause.

The opposition you are expressing is already way more rational than the Billy Bob redneck youtube conspiracy expert I was debating on facebook. Which is to be expected, because HN. You of course are correct about the cyclical event stuff... however, there is a ton of evidence that the current rate of co2 output[1] and heating[2] is unprecedented in human existence[3]. All that I ask from anyone on either side of this debate is that you check your sources and make sure your info isn't coming from some partisan think tank.

[1]http://www.esrl.noaa.gov/gmd/ccgg/trends/

[2]https://www.wunderground.com/blog/JeffMasters/august-extends...

[3]http://earthobservatory.nasa.gov/Features/GlobalWarming/page...

No, you're right that there are different levels of proof in different sciences. I think that we lose each other in these discussions when we forget that. But it makes sense to have a different burden of proof for statements about different aspects of the world.

The Physics equivalent of the broken statue is a 2-sigma result. It's less interesting there because it's easier to repeat the events leading to the result.

Speculation is a powerful component of Science and it's easy for us to mistake a scientist's speculation for a sound fact.

History is a science in the broad sense as it uses verifiable data about the historical record to make conclusions about what occurred. In that regard it isn't much different from other sciences that study the non-historical past, such as paleontology or physical anthropology. That being said, not every piece of data or conclusion drawn in history is equally valid. Much like with natural sciences, you have to consider the very real possibility that when one person or group of people come up with a radical new conclusion that they are mistaken. It's always safer to stick with consensus views unless you know a particular subject well and can judge the merits yourself. If a new idea really is valid, eventually it will become part of the consensus.

Anti science? Offering an opinion on the potential shortcomings of a scientific theory isn't anti-science. Discussions of land bridges once touched on some rather dark assumptions regarding the abilities of past peoples, specifically outdated notions that "primitive" cultures could not travel oceans. It is very scientific to hold them to standards based on what we now know about these cultures. Thor Heyerdahl was not "anti-science" when his work challenged land bridge assumptions.

It doesn't matter what evidence this theory is backed by. What matters is the sum total of all available evidences, especially outside evidence not addressed initially. I do not subscribe to this theory because it does not address several pieces of available evidence that other theories better address. What is anti-science is the blind acceptance of theories that are at best internally consistent.

(Not a historian and only skimmed the article for reasons below): I take these sorts of presentations of data with a grain of salt when the article says something to the effect of "our old, sweeping theory that we presented as reliable history was wrong, so here is a new sweeping theory based on a couple new findings which we will now present as reliable history." So I quit reading as closely. I might prefer a more clear delineation of what is evidence and what is speculation. Interesting nonetheless.

It wasn't anti-science, but you should generally be cautious every time someone makes a sweeping claim. There's been a lot of stories here about science journal bias, poor research, and bad studies. Science is not a synonym for accuracy or truth.

Replying to myself to address several different replies.

I see history as a "hard-enough" science. You can gather a lot of various evidence, use a lot of tools based on science (carbon-14 dating) and evidence published by others to understand a plausible scenario and extend it through new theories. I suppose this is what was also meant by "empirical." Unlike some science goal such as describing the orbit of the planets or the nature of our galactic center, history tries to find true statements about the past.

Even more realistic than the Lincoln example is the historicity of Jesus [1]. Billions of people talk about a person who lived 2000 years ago and we don't know whether he was a real person or not. Either he existed or he didn't, and we can apply many tools of historical study to try to find an answer. And the best we have is that theories for it that seem stronger than those against it.

When I wrote that the comment [2] was "practically anti-science", I was referring to the pop-science aspect of it, where you just have to present some new and flashy idea to get attention. I'm also a proponent of viewing pre-historic humans to be just as intelligent, complex, and capable as modern humans, so I mostly agree with the ideas of the comment. For example, the colonization of Pacific islands by Polynesian navigators over vast expanses of open water is well attested. But just pointing this out is not sufficient. You need an entire scenario (theory) of what plausibly happened: the climate was thus, and the terrain was thus, and this supported X humans who moved thus, and that explains the population numbers we see later, and all this has to be based on archaeological and geological evidence.

I think I was reacting to the tone of the comment, mostly. It struct me as the slightly informed personality who jumps into a scientific debate with his own pet theories and criticizes the others for not considering them. I think it's safe to say that the researchers who work in these fields have probably considered these pet theories, and are working on their own theories for a variety of reasons (no evidence, not realistic, or simply too busy with lots of work to investigate that line of thought at this time). The comment seems to believe the researchers did not consider these theories, when in fact we don't know whether they considered them or not.

I'm all for popular input into science, and I actually identify as a person who spends 10 minutes on Google/Wikipedia (and HN articles) to understand something. Often these people have a broad range of interests and can bring in ideas and details that may be overlooked. And I even celebrate people like Thor Heyerdahl who float new theories and go the extra mile to experiment and provide new evidence. But they can't jump in the middle of a scientific debate and claim to have it all figured out and have people take them seriously.

So whether it's a comment on HN or somebody's pet theory in a book, I feel it has to respect and acknowledge the existing science and provide evidence for itself, and avoid the sensationalized or know-it-all tone of pop-science.

[1] https://en.wikipedia.org/wiki/Historicity_of_Jesus [2] https://news.ycombinator.com/item?id=12562466

The map is interesting. I never knew the Aleutian Islands marked a former continental coastline.

>This new picture raises a key question: did the first migrants to the Americas really race over Beringia just as the great ice sheets were melting?

I'm not sure that I subscribe to land bridges as gateways for early humans to move between continents, especially in the north. The Inuit/Eskimo peoples are and were perfectly capable of moving and living on water, frozen water but water nevertheless. Humans need not have waited to walk across dry land bridges. They were perfectly capable of migrating along ice sheets, or even setting out into open oceans. It would not have been much fun, but the journey would have been made either deliberately or by accident.

They did set out into open oceans, it was the only way to get to Australia and that was populated long before the Americas.

Australia was also settled during a glacial maximum so the coastline extended out much further than now.

The distance the first migrants to Australia might have needed to travel across open water might have been as low as 90km.

https://en.wikipedia.org/wiki/Prehistory_of_Australia#Arriva...

A few things to keep in mind:

1. Australia was probably settled well before the Glacial maximum.

2. We don't know much about the coastline, a rocky, volcanic island wouldn't have been a great help to the migrators.

3. They islands they had to go through is a geographically active region (it's possible some people in the migration witnessed the Toba eruption), so knowing where the coastlines were is difficult.

4. Is there a standard for what's considered open ocean? I would consider 45Km to be included, but then again, I would consider grater than 0.1Km to be open ocean.

4. Yes, but it varies by domain. I think the military definition is the more useful one here: https://definedterm.com/open_ocean There are rivers over 100m wide so I don't think that would fit most people's definition.

The definition of "open ocean" in my area is that part of the sea unconstrained by the effects of land masses, ie open. It's where waves are defined by wind alone, without any obvious influence of land or shallow.

Another version would be those areas where ships may navigate freely without worry of obstructions. That would mean, for sail, that some areas are open or not based on the direction of the wind.

The constraint being assumed here, I think, is that it would take a very long time for regular people travelling at a regular pace, and not really knowing where they're going (rather than, say, soldiers on a forced march to a known destination) to cross the Bering strait. It would be longer than preserves would last; it would be longer than bodily essential-nutrient stores would last.

Humans need to eat plants. Even the sub-arctic tundra supplies plants to eat, in the summer. But arctic tundra doesn't, and ice sheets certainly don't. Migrating from the arctic tundra in Sibera, across an ice sheet, and then back across the arctic tundra of the Yukon, before finally reaching sub-arctic tundra, would likely take years. It would destroy a person.

The advantage of a land bridge isn't that it's not water; it's that it's not ice. It is—for at least some part of the year—arable.

Believe it or not, Eskimos on the ice eat seals.

I don;t think we need plants. If you east whole animals, livers and all, then I believe it possible to survive for an extended period. You won't be happy, but alive.

The Bering Strait is only 53 miles/85 km wide, and the native peoples of Alaska and Siberia routinely crossed it in their indigenous boats (and over the ice, in winter).

Also, there are plenty of plant foods available at the latitude of the Bering Strait.

That doesn't really say anything one way or another about the premise of this article, but it's simply not true that a land bridge was required.

A water route for the early migrants makes a lot of sense. There was a study published in "Nature" a couple months ago that looked at samples from sediments at choke points on the land routes, and determined that it took several hundred years after the routes opened for vegetation and then animals to appear [1]. During that several hundred years, migrating humans passing through would not be able to live off the land. They'd have to have brought their food with them.

Note that this was before the invention of the wheel, so there would be no pulling your supplies with you on a cart. It was also before domestication of any animals other than dogs, so no pilling your supplies on a horse, or having a horse drag a sled.

They also would not know how far they would have to go to get to some place that could support them, so would have no idea how much food to take. With the limitation of only being able to take what they could carry, or get dogs to carry, or get dogs to pull on sleds, I doubt that they would have enough to make it through.

It's only after the plants and animals get well established, so that you can live off the land, that it becomes reasonably feasible to migrate that way.

The Clovis culture was well established long before that, so they had to come some other way,

A water route avoids these problems. First, you can carry a lot more with you when you go by boat. You can either make your boat bigger to have room for your supplies, or you can tow a supply boat or raft. (Ropes had been invented by then).

Second, you can fish. I don't think the technology of the time would have caught much in the open ocean [2], but if they stayed reasonably close to coastlines they should have been able to catch plenty of fish. (Following coastlines might also be a good idea so they could go ashore now and then to try to find fresh water).

What I don't think I've ever seen discussed is when did anyone go the other way? Presumably at some point someone came back and so people in Asia became aware that those who headed east and were never heard from again weren't all starving to death or sailing [3] off the edge of the world or whatever.

[1] Here's an article about the study: http://www.history.com/news/new-study-refutes-theory-of-how-...

[2] the open ocean is sometimes described as a "biological desert" because of the sparseness of life there, especially life reasonably near the surface (and so where ancient fisherman could reasonably have a shot at catching it). The overwhelming majority of ocean life is in the shallow seas above the continental shelfs.

[3] well...rowing. This was before sails were invented.

I agree, but think we are falling into the trap of assuming that the migration was in some way planned. I'm picturing more a band of people pushed to sea by an unusual storm, or traveling along the ice sheet to escape from some other people. They don't have to live or east well, just survive the journey. If following currents/winds that journey may have only been a couple weeks. Think of all the terrestrial species that have crossed oceans on driftwood.

(Boats 'sail' without sails. Wind pushes everything. It's not fast or efficient, but even a dugout can make plenty of progress on wind and current alone.)

> I don't think the technology of the time would have caught much in the open ocean [2]

> [2] the open ocean is sometimes described as a "biological desert" because of the sparseness of life there, especially life reasonably near the surface (and so where ancient fisherman could reasonably have a shot at catching it). The overwhelming majority of ocean life is in the shallow seas above the continental shelfs.

There's more than enough to feed you as you voyage through the open ocean. For unknown reasons, fish are attracted to anything that floats on the surface, so they'll come to you. This is, in fact, our current technology for catching dolphin-safe tuna -- release a bunch of "floating objects" into the sea, let them accumulate all manner of sea life, and sweep it all up.

People lost at sea on rafts don't starve. Exposure is a major issue; food isn't.

> The Inuit/Eskimo peoples are and were perfectly capable of moving and living on water

Suprisingly the Inuit are a very young culture! They started around 1000 AD in Alaska and had settled northern Canada and Greenland only when Europe discovered America.

https://upload.wikimedia.org/wikipedia/commons/3/32/Arctic_c...

The Paleo-Eskimos (genetic studies show no connection to the Inuits, so no intermarriage) developed 2500 BC (and ended 1500 AD), so only 4000 years ago, this is way after the migration of Paleo-Indians into the American continent (40,000–16,500 years ago).

I didn't mean to say that they were the culture that made the crossing. They are proof that the move was possible using only the resources available at the time.

Yes, the Dorset culture was basically genocided by the Inuit. The Inuit actually still have stories about it.

Apparently someone doesn't like the word "genocide" here.

The Dorset were wiped out so thoroughly by the encroaching proto-Inuit that they didn't even leave any genes behind. What would you call it?

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