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Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

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Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#81

Post by naikrovek »

defrost wrote: post #12
TulliusCicero wrote: post #6

How do the LIDARs work for this kind of thing? I always imagined that the light used wouldn't be able to penetrate objects that are opaque in the visible light spectrum.

If sunlight can reach the forest floor then so can LIDAR. An airframe with a LIDAR device scatter shots a medium angle "spotlight" of pulses at high frequency downwards within an arc area of angles (straight down, a bit to the left, a bit to the right, a bit forward, etc.) Of the tens of thousands of 'RAW' data points many reflect from top canopy leaf cover, many penetrate further, a lesser number reach the ground. A…

Why do tree trunks not show up?

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#82

Post by defrost »

naikrovek wrote: post #81
defrost wrote: post #12

Earlier quoted context omitted.

If sunlight can reach the forest floor then so can LIDAR. An airframe with a LIDAR device scatter shots a medium angle "spotlight" of pulses at high frequency downwards within an arc area of angles (straight down, a bit to the left, a bit to the right, a bit forward, etc.) Of the tens of thousands of 'RAW' data points many reflect from top canopy leaf cover, many penetrate further, a lesser number reach the ground. A…

Why do tree trunks not show up?

Standing or fallen?

.. and who says that fallen logs don't show up?

Bear in mind that the final display is a processed data product with any number of artefacts smoothed, filtered, or cut away by a data processor.

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#83

Post by AlotOfReading »

vdupras wrote: post #67
nico wrote: post #55

Earlier quoted context omitted.

The show seemed very convincing, not in the speculative theories about an ancient precursor civilization necessarily, but definitely in some of the findings they show Do you have any resources you could share that debunk the specific things they show? Like the rock paintings they dated to 10k years ago, or some of the other digs that were dated as 20-25k years old? Are you saying it is all made up? Or just some of it…

This is precisely what I'm looking for too. All critiques of Hancock I can find with my feeble googling skills seem to be focused on unimportant stuff such as encouraging uses of psychedelics and accusations of racism. But what's far, far more important, is debunking evidences like rock painting dating, geoglyphs dating. That thing on Rapa Nui about statues being more-than-half buried seemed really intriguing. The sp…

The moai are half buried because that's just what tends to happen in erosive environments. Sediment buries things.

As for specifically debunking his LGM speculation, there isn't much because no one with public credentials wants to spend time and effort on it in the current academic environment. You can find debunkings in popular media (https://www.youtube.com/watch?v=-iCIZQX9i1A) and a few scattered "popular" academic publications like the SAA's special edition on Hancock's pseudoarchaeology (http://onlinedigeditions.com/publication/?i=634462&p=10&view...), but most of the information is buried in papers and books that don't discuss him at all.

There's just flat out no actual evidence for (virtually?) all of his speculation and you can't prove a negative. Hancock's MO is to take 1-2 anomalous results and spin out media around "these dates don't line up, so let's speculate about something entirely unrelated". The rapa nui episodes in Ancient Apocalypse S2 talk to one actual archaeologist, who doesn't even support the dates discussed in the episodes. They were just anomalous banana phytoliths that were present from sediment intrusions. Dating is hard and this stuff happens regularly, especially in areas without much active research like Rapa Nui. The standard understanding is post-1200, as documented in papers like https://doi.org/10.1016/j.jas.2020.105094 and https://doi.org/10.1038/s41586-021-03902-8

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#84

Post by gonzo41 »

tenpies wrote: post #58
gonzo41 wrote: post #9

Earlier quoted context omitted.

Every time i see these I think about Spanish explorers who brought small pox over and caused these cities to collapse, only to return to Spain telling stories of jungle cities. Only to have the fleets turn up to dense jungle years later and fine nothing. But yeah, I also think about lost treasure and Indian Jones a lot with these stories.

I think you are referencing La aventura del Amazonas by Dominican monk Gaspar de Carvajal. He was one of the survivors of the first European expedition through the Amazon and provides the only account we have of something resembling the pre-European Amazon. He talks about large cities with tall structures, roadworks, and very elaborate societies - nothing compared to our common notion of the Amazonian people. His acc…

This is what a meant yes. I just couldn't find the reference. Thank you.

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#85

Post by pegasus »

desdenova wrote: post #11
gonzo41 wrote: post #9

Earlier quoted context omitted.

Every time i see these I think about Spanish explorers who brought small pox over and caused these cities to collapse, only to return to Spain telling stories of jungle cities. Only to have the fleets turn up to dense jungle years later and fine nothing. But yeah, I also think about lost treasure and Indian Jones a lot with these stories.

Some of those ancient cities disappeared a lot earlier than Spain even existed, though. People likely abandoned them for some unknown reason and moved to other locations, where they'd eventually get wiped out by the Spanish.

Most of the cities disappeared earlier.

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#87

Post by alganet »

hosh wrote: post #59
PittleyDunkin wrote: post #49

Earlier quoted context omitted.

> I think that minimizes the fact that people were deliberately curating and designing perennial food forests, historically and contemporarily. I don't see this minimization (after all, we currently do this unintentionally today and nobody sees this as lack of intelligence and I certainly hope I never implied that people in the past were in any way less capable than ourselves) but I do affirm that people were just as…

I've been on a quest to find out what went wrong with modernity. Looking through the history, I found out the Renaissance was not what I thought it was. The history of the Silk Roads were not what I thought it was. And I haven't revisited the history of the industrial revolution, but it looks so far, that is where the obsession with maximizing productivity, gains, and work all come from. It is very likely when I look…

> I've been on a quest to find out what went wrong with modernity.

The late bronze age collapse. Humanity fucked up so bad we don't even know what happened. Everything since then has been meh. Future humans might still see us as in some form of iron age.

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#88

Post by austin-cheney »

neaden wrote: post #31
ryleyrandall22 wrote: post #20

The Book of Mormon has made this claim for years

There is absolutely nothing being found here that is consistent with the Book of Mormon besides very general things like people lived there.

In all fairness the science at this point also makes no further claims.

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#89

Post by austin-cheney »

ryleyrandall22 wrote: post #20

The Book of Mormon has made this claim for years

There are a couple of things here to prop up your comment:

* The BOM mentions multiple disconnected societies that go way way back and over simplified them with the label Jaredites.

* That over simplification of the Jaredites is present at the beginning of the Bible’s Genesis too when Able was cast out and went to one of two neighboring cities. That indicates others outside the faith existed in the locality of the faith but were largely ignored, perhaps a perspective thing. These weren’t meant to be history books.

* The BOM itself is a self described radically abridged work. The book describes at one point a small library worth of religious texts, social history, and likely a variety of secular things that people find more practical day to day. These works were lost during a social collapse. The BOM is a tiny portable collection of religious works taken and compiled by a guy named Mormon and carried by his son Moroni. The word portable there is debatable because the book was made of gold and gold is ridiculously heavy, but nonetheless the book describes being hand carried some distance.

Re: Laser mapping reveals oldest Amazonian cities, built 2500 years ago (2024)

#90

Post by underlipton »

PittleyDunkin wrote: post #66
hosh wrote: post #59

Earlier quoted context omitted.

I've been on a quest to find out what went wrong with modernity. Looking through the history, I found out the Renaissance was not what I thought it was. The history of the Silk Roads were not what I thought it was. And I haven't revisited the history of the industrial revolution, but it looks so far, that is where the obsession with maximizing productivity, gains, and work all come from. It is very likely when I look…

> treating it as the most probable theory (and then making decisions based upon it) is something I have concluded for myself as folly. Sure, but your tools reasoning about the past are quite limited. Occam's Razor helps us identify where narrative elements are unnecessary for an explanation, and in that it's quite useful. For most of history we must rely on Occam's Razor to even construct any sort of probability mode…

You're misusing Occam's Razor because of a misunderstanding about indigenous people's capacity for engineering.

https://www.jstor.org/stable/24712701

https://worldoceanreview.com/en/wor-8/targeted-interventions...

https://www.si.edu/newsdesk/releases/indigenous-peoples-have...

Native Americans in the Pacific Northwest actively encouraged the formation of geological structures in order to increase shellfish yield and sustainability. You seem to think that the simplest explanation is that people just copied happy accidents, when the level of sophistication of these systems combined with the documented propensity of humans to actively engineer their way out of problems leads to the simplest explanation being that what we see with both the food forests and mariculture is such active engineering.

The only way to come to a different conclusion is to assume that something is fundamentally different between Old World and New World populations just because one group's processes are relatively well-documented and the other's isn't. However, that conclusion would be colored by your relative inexperience with the shape of New World solutions. We're just discovering these phenomena because we didn't have the vision to see that they existed, biased as we are to the Eurasian perspective. If all you know are wheels, you won't recognize llama tracks, as it were.

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