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Using Lidar to Analyze Chacoan Road Profiles - Ep 208
931 Plays1 year ago
We’re talking about Chacoan road networks again! A few years ago we interviewed Sean Field. He was doing research on the road networks coming into and out of Chaco Canyon. Sean Field is at it again with another paper but this time he’s using Lidar to analyze road profiles. It’s an innovative technique and Chris and Paul discuss it on this week’s show.
Transcripts
For rough transcripts of this episode go to https://www.archpodnet.com/archaeotech/208
Links
- “Lidar Derived Road Profiles” - Advances in Archaeological Practice: https://doi.org/10.1017/aap.2022.31
- Archaeotech 117 with Sean Field: https://www.archpodnet.com/archaeotech/117
Contact
- Chris Webster Twitter: @archeowebby Email: [email protected]
- Paul Zimmerman Twitter: @lugal Email: [email protected]
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Transcript
Introduction to Episode 208 and Lidar in Archaeology
00:00:00
Speaker
You're listening to the Archaeology Podcast Network. Hello and welcome to the Archaeotech Podcast, Episode 208. I'm your host, Chris Webster, with my co-host, Paul Zimmerman. Today, we talk about using lidar to analyze prehistoric roads.
Remote Archaeology Project Management Challenges
00:00:18
Speaker
Let's get to it. All right, everybody, welcome to the show. Paul, back in the States again for a brief period of time.
00:00:29
Speaker
Just very brief. Tomorrow afternoon, I am flying out. Tomorrow morning, I'm leaving the house, so I better get packed real soon here, and then I'm going to spend another month plus in Saudi Arabia again, doing this weird kind of hybrid PM field director sort of job that I'm doing. Looking forward to it. There's been a lot going on, and trying to deal with some of the stuff remotely has been, let's just say, a challenge. So it'll be good to actually be there in person and crack heads when I have to.
00:00:59
Speaker
I can imagine. It's never good trying to manage stuff remotely, especially fieldwork. I don't even know how you would do that. That's ridiculous. Good on you for that one. My counterpart that's out there right now, she's been very good and she's been very diligent. It's too much for one person. We have a standing meeting every day and we discuss the problems.
00:01:22
Speaker
I tried out from my perspective and some suggestions about how things can be dealt with. Most of the issues we have are around staffing, but there's occasional stuff. We're working with engineering companies and you give them an inch, they take a mile, and we have to set boundaries, know when to put our foot down on things, know when to escalate things to the hires up in the company, that sort of stuff.
00:01:45
Speaker
And if we're there in person, we can talk about this stuff in person. But as it is, everything's got a day to lay before she can tell me. And by then, it's late in the day for her. And it's first thing in the morning for me. And so it's a challenge. It's a fun challenge. But I'm looking forward, actually, to getting back out there and dealing with things directly.
00:02:05
Speaker
I'm curious logistically, since we talked archaeology and stuff on the show, I'm curious logistically, are they cycling people back to the States just to kind of prevent burnout, or did you request that? I'm just wondering. I had to come back because of some family things, so I had a court date. I didn't do anything bad. It was the resolve of problem with taxes that wasn't mine. It was my problem to fix, but it wasn't mine that started it.
00:02:34
Speaker
So that was yesterday. And yesterday also happened to be my anniversary. So, you know, things coincided nicely. You know, it's nice to keep those things in check, you know, make sure you're checking all the boxes there. Yep, absolutely. But yeah, we do try to cycle people through because we want to build up a stock of really good people who know the area and know that the materials work well together.
00:02:58
Speaker
And that means getting them out there for good long periods of time and then getting them back home so they can recover a little bit.
00:03:05
Speaker
Yeah, absolutely. It's good logistics to do that, right? You don't want people to burn out and just not have that, especially being over in a foreign country like that. No, we don't want to burn through them. Yeah, for sure.
Introduction to Sean Field's Lidar Research on Chaco Roads
00:03:18
Speaker
All right, cool. Let's talk about our topic today. So we're discussing a paper that we saw recently in Advances in Archaeological Science, our source for lots of things on this show.
00:03:29
Speaker
And the paper is by Sean Field. It's called Lidar Derived Road Profiles, a case study using Chaco roads from the US Southwest. And both Paul and I were like, this sounds real familiar. So I went and looked. And episode 117, November 28, 2019, we did a show called Analyzing the Chaco Road Network. And we interviewed Sean Field, the author of this study.
00:03:54
Speaker
more work on this, you know, post pandemic and pre pandemic last time. So I don't know how his how his fieldwork changed or if anything was had to be done differently. But it's pretty cool to see him continuing on this and continuing to publish on this topic.
00:04:07
Speaker
Yeah, and it's really a cool evolution of what he was working on before. I mean, the article in and of itself makes a lot of sense, but also in terms of what we know from his prior work, it grows from that and it explores new tech ways of dealing with mapping and understanding this road network. And so that just from a meta perspective was really kind of interesting to me just to
00:04:31
Speaker
to see the evolution, the development of his own methodology and his own tech chops and everything. I would like to talk to him again about this. Yeah, I mean, hopefully we can get him on because it would be nice to have that follow up because I'm interested too.
00:04:47
Speaker
A lot of people only put together papers often for the things that worked. What else has he tried in order to analyze these roads that actually didn't work? Are there papers about that somewhere that maybe didn't make its essay advances and might be somewhere else along those lines? But regarding that, talking about these road networks,
00:05:07
Speaker
It's actually pretty cool studying these because a lot of people have studied the Chaco and road networks in the past. And for anybody that doesn't know what we're talking about, Chaco Canyon, north, western, New Mexico, you know, big cultural area had a really high point for about what, a thousand years or something like that, give or take, where there was a lot of people there, settlements all over the place, Pueblo Benito, big famous one that's down in the canyon. If you ever have a chance to go there and see all that stuff, oh my God, it's just
00:05:35
Speaker
It looks like people lived there yesterday. It's crazy. Yeah, it's really neat. And as a side note, the supernova pictograph is there, which was, I really love that thing, which was really cool because it's got correlation with other networks. I think it was written about in Greece, definitely China, and I think Egypt as well. The supernova that was visible during the daytime at one point back in like, it was around 1200 or 1100 or something like that, if I remember right, AD.
00:06:04
Speaker
And it was noted by multiple societies, including this pictograph that was put up on the underside of a rock ledge in Chaco Canyon, which is super cool.
Road Networks Across Cultures: A Comparative Analysis
00:06:14
Speaker
So anyway, all that's really neat. And he starts out just by saying hi there, studying this stuff with, you know, understanding how people moved around this network with Chaco Canyon kind of being the hub and moving to the outlying facilities and not facilities, but I guess villages and settlements and camps and how people use that to
00:06:34
Speaker
basically stay in touch and to trade and to have that interaction. And it's interesting to understand the evolution of these roads and how they were constructed and how they were used to facilitate this network.
00:06:46
Speaker
Yeah, and it's one of those things a lot of societies in this part of the introduction, you know, roadways are important components of it. And so he talks about elevated roadways in South America. He talks about the Roman roads. I mean, Roman roads is a thing that we all know about as a term, as an idea, even if we don't know any of the details.
00:07:05
Speaker
The existence of them is one of the kind of cool cross-cultural anthropological things about humans that you can compare from one society to another. And then like so many other things, religion, cuisine, whatever, architecture, go on down the list. There are different takes on, different ways that things are made, different ways that things are done, different reasons, different underlying reasons and different proximal reasons of why people make their roads in the places they make them and in the ways that they make them.
00:07:34
Speaker
And so he starts analyzing that, trying to get a little bit of sense of what makes this road network uniquely Chacoan. What really interests me about that as well is I guess it's really visible in places like Nevada, right, where you've got some trail that's listed on a map from like the 20s that's now Interstate 80 or something like that. You know what I mean? How some of these old roads that may have started out as, you know, initially used by Native Americans for sure to transit
00:08:03
Speaker
you know, common pathways, like maybe there's a river in the way or there's a path. So everybody's going to kind of take the same path in that case. And it's a path of least resistance, so to speak. So it makes sense to have a road there. It's really interesting to me that most of the stuff in and out of Chaco has just never been developed because nobody ever moved to Chaco Canyon after this, right? The only people that moved there was the national park service.
00:08:23
Speaker
So it would have been interesting to see how that would have developed. You know, these all would have been destroyed. And would people have been using the same network of roads? Because like I said, in Nevada, there's what is it? Well, there's I-40 down there. I know like the Route 66, not in Nevada, neither of those in Nevada. But in Nevada, you've got Interstate Highway 50.
00:08:42
Speaker
And you see the new road, but then in some cases on corners, you can see like the pavement from the old road, you know, out all broken up on the side of a hillside or something when it was a two lane little road that, you know, just kind of followed the hills. And that's, I mean, that's along the same lines of what we're talking about. Somebody's going to analyze that later on and discuss what these, you know, how important these roads were and how they were maintained in order to keep them useful.
00:09:06
Speaker
Yeah, the part of New York where I live here an hour north of New York City. Tons of roads like that. Route 22 is just a couple miles away from me, but if I drive up Route 22, it gets intersected in a bunch of places by old Route 22. Along the way, as car travel became more important, they went from this meandering sort of
00:09:27
Speaker
horse path to a bigger roadway that was straighter and for whatever reasons followed what was considered a better line. But you see that, you see the evolution of these things through time. And it's really easy to if you're in a place like where I am and you just look out and there it is on the road signs.
00:09:48
Speaker
I know. It seems like the evolution of the modern road is generally straighter and wider. And that's about it. Which makes me wonder if, you know, kind of getting off the rails a little bit here as we get into an era of potentially self-driving cars. I mean, those are coming down the line whether you want them or not. So, you know, self-driving cars and just a different way of using the roads rather than relying on people, relying on software to kind of manage this, we'll be able to have a different style of road system. And it makes me wonder if
00:10:17
Speaker
you know, they'll continue to be, they wouldn't need to be as wide, I'd imagine. So we could probably have narrower roads in the future just because they'll be more efficiently used by computers rather than people trying to jam in and don't know how to use the zipper method to merge onto an interstate. Self-driving cars know how to do
Podcast Logistics and Membership Benefits
00:10:33
Speaker
that. So I'm thinking traffic will be a thing of the past, but it would be interesting to see what our connection to roads would be.
00:10:38
Speaker
because you know more than likely we'll be inside of a car with the windows all opaque and we'll just be playing video games reading you know having a meeting doing whatever we're doing but not driving and it'll be interesting to see that but anyway you're not driving right now are you
00:10:54
Speaker
Uh, I'm currently not driving, but I'm in my car, which is also my home. Right. Right. Exactly. Exactly. All right. Let's take a short break and then come back and see how Sean used Lidar to study these roads in a way that really hadn't been done much in the past back in a minute. Welcome back to the architect podcast episode two Oh eight. And we're talking about Sean Fields article.
00:11:19
Speaker
in advances in archaeological practice. It's available. Go check it out. We're linking to it here in the show notes. So Lidar derived road profiles.
Analyzing Ancient Roads with Lidar and R Programming
00:11:28
Speaker
And really, we do mean profiles, you know, something looking at it from the side, you know, a profile, because he mentions lots of people have used Lidar to find roads. Right. Because roads typically will have either a depression and or some sort of berm or something that you can see that are often in straight lines that nature is has a really hard time making. So when you're looking at a surface, Lidar's
00:11:49
Speaker
relatively easy to use as long as you don't have like a ton of things obstructing it like different vegetation that the lighter perhaps can't see through although lighter is Notoriously good at seeing through vegetation. So yeah that really resonated with me I mentioned on this show a couple years ago how we were working on a project near the Hudson River and We knew that there were roadways there
00:12:11
Speaker
Yeah. But they were really hard to find. And then I found a one-meter dam of that area, Lidar Dam. And I looked at it and didn't see much because I was doing it in the regular grayscale because I don't like hillshades. And then just for giggles, I put it in the hillshade and boom, all these roads popped up.
00:12:33
Speaker
Some of the mapped opto-human structures that we were looking at the foundations of were clear as day in that, and in relation to the roads, and all this stuff just popped. So he does talk about the use of Hillshade as one method that people have used, and so he's testing out another one, but it's also the same kind of a dataset being LiDAR based. But yeah, so I have that kind of not rigorous, very
00:12:56
Speaker
one-off sort of accidental use of lidar to find roads. And it's neat to see what somebody does with the rigorous methodological approach to this. Yeah, for sure. I don't remember reading in this because I read it like a month ago when we were going to talk about it and then skimmed it over again today. This is readily available lidar data he got here, right? This was already collected. He didn't collect this lidar data from somewhere else. I don't remember. Do you remember that?
00:13:22
Speaker
Yeah, I was skimming too, because I had the same question just before we came on air. And I didn't see where it came from. But I think that if it had been custom gathered for this, then it would have been mentioned a little more prominently. Yeah, probably. Although that wasn't really the focus of the article. It was just about using the LiDAR. No, it wasn't. It was what you do with the LiDAR data, not the fact of the LiDAR data.
00:13:45
Speaker
Yeah, indeed. And the study area too is really massive. It literally is the entire corner of Northwest New Mexico. Well, not the whole corner, but a large portion of a corner of Northwest New Mexico. Because these Chacoan roads on figure one in the article, if you're following along, really shows how far out these networks really extend and then where things are in relation to all that. And then that's matched up with the
00:14:08
Speaker
with a lidar image of a road that just pops clearly like somebody laid a stick in the sand or something like that on a beach. Yeah. I mean, that's what the road looks like, but it's massive. So yeah. So basically what he does.
00:14:22
Speaker
As he's in the study, he's taking various segments of these roads, things that had been previously known. He's not using it to identify roads, not at this point. People have definitely done that and done that successfully, but that's not the interest of the article, which I thought was an interesting take. It's really at characterizing the roads.
00:14:40
Speaker
So he's taking known ground truth segments of roads and then generating these profiles programmatically in R every half meter along. I mean, to the point that they've got about 84,000 different transect profiles generated with this program, which is, wow, that's a lot of data. And then the code for the program is up on GitHub and that's fantastic. I love when people do that.
00:15:06
Speaker
So, that makes me pleased. The crux of the article really is what's done with those profiles, how the data are massaged in order to try to compare one set against another.
00:15:17
Speaker
How familiar are you with R, just out of curiosity? Yeah, so I've mentioned before, I'm not a fan of R. I totally get why people are. No pun intended, but I'll stick it with it. I totally get why some people are, but it just doesn't make sense to me. And so I think I compared it once on here with using left handed scissors. I'm very right handed.
00:15:42
Speaker
And if I try to use left-handed scissors, I either screw up because I'm using my left hand, which isn't very good, or I try to use it with my right hand and the angle is all wrong and I don't. So that's what R is like for me. I really get why some people love it. And I've seen fantastic work that people have done with it. It's one of those tools that if you're good at it, if it resonates with you, there's fantastic work that's being done with it. So more power to anybody who can.
00:16:11
Speaker
I really only ask because I really don't know a whole lot about it other than what we talk about people using it for in some of the stuff that we talk about. I've never used R myself, never really studied it that much. I actually did a workshop in R one time at a conference. It was so long ago, I didn't even remember it. So that's pretty much useless at this point. But the fact that Sean used R to essentially slice up this model into these nearly 84,000 transects wasn't really something I had
00:16:41
Speaker
thought that R was used for. I thought it was almost more of a statistical thing rather than a tool like that. The first time I saw R being used for spatial processing, it was in a lecture a bunch of years ago now by Sebastian Heath, who's also been on this. He's a professor at New York Institute for the Study of the Ancient World.
00:17:02
Speaker
I thought that is madness and I really dig it. But since then it's become a very legitimate spatial analysis tool. Again, one that I don't use, I gravitate more towards Python for things. It's totally legit and a lot of people use it to great effect.
00:17:20
Speaker
One of the things that he was doing with this, with these transects anyway, really just cross sections of these roads in lots and lots of different little places. And it's really only, what am I looking at here, like 10 roads, eight roads, something like that. And all of them had certain number of segments to the roads because maybe they weren't totally contiguous, but they could tell where they were here. And then they had the length of the segments. The longest one looks like it was about 11.
00:17:42
Speaker
kilometers give or take and that one had 23,000 transect lines so they were really he's really taking a look at this but here's the thing
00:17:51
Speaker
He's using the LIDAR derived data to basically take what's visible on the surface about this road. And there's no backhoes here that are cutting a transect across these roads or anything like that to really look at this photography of previous road construction events or if that's even visible with these. It really is a surface level, literally a surface level analysis of the shapes of these roads. And the interesting thing about that that I thought was
00:18:17
Speaker
that he's using that to compare those profiles and what we know about the profile with ground truth roads, so ones that either he's seen or somebody else has, but either way he's got data for it and saying, what does this tell us about the ground truth road that we can say as a control? And then looking at the non ground truth roads, the ones that maybe nobody or maybe just him hasn't visited and saying, okay, so what can we infer about this based on the profiles that we have and what we know about the ground truth roads? It's a really cool way to do it without
00:18:46
Speaker
I mean, honestly, with minimizing your fieldwork, which is expensive, but getting some really valuable data done as well and doing this. So it's pretty cool the way he did that. It seems that there's a lot of work going on now between remote sensing of various kinds and ground truthing.
Evolution of Road Studies and Technological Integration
00:19:03
Speaker
I can't talk about it much, but one of the projects I worked on last year involved doing a lot of pedestrian survey to verify sites that were identified with machine learning. And we found that it was really strikingly accurate at finding sites. The sizes and the shapes of the sites weren't always the same once we got on them versus what the computer had picked out, but the locations of them was really, really good.
00:19:31
Speaker
Was it done predictive modeling? Was it looking for where it thinks sites should be? Or was it fed information regarding land size shapes and things like that, like Lidar models and stuff like that? What did it use to find the sites? I wasn't involved in any way, shape, or form on that side of it, so I can't tell you what the inputs were. I would guess that knowing the people who were doing it was everything that he'd get, including some other survey work that we had done.
00:19:56
Speaker
Right. So they had known targets of various kinds of sites. They had known geological maps. They had slope and aspect and all that sort of stuff. And I think they just fed everything they could at the computer models and started getting out areas of high probability and then those ones of highest probability.
00:20:16
Speaker
We had archaeologists looking at them in satellite and aerial photos and saying yes or no. And then the ones that got the yes, those are the ones we went to go look at. Right. OK. Well, that's really cool. What were you going to say before I interrupted you on that?
00:20:32
Speaker
No, no, and I was also going to say about ground truthing, a little bit of a bribe here, but we've got an article that just came out in the Journal of Anthropological Archaeology. I'm a co-author on, and it is specifically about ground truthing because it's a response to another article that came out last year, made a lot of buzz because it tries to basically
00:20:54
Speaker
argue for a very different configuration of Sumerian cities than it's typically envisioned. But that article is based entirely on remote-sense data, and our contention is that it wasn't done right because it doesn't match what we find in excavation and in the coring that we're doing on that site. You and I both love remote data. I do a lot of it.
00:21:19
Speaker
But I also love ground truthing things. And I know that these two things have to work in concert. I mean, it has to be done, right? The more that we ground truth this remote data, I mean, the more accurate it becomes. The more we're able to really do some good predictions. I keep thinking back, especially with this whole LiDAR server here, it's really got me thinking. And you're talking about finding sites last year based on machine learning.
00:21:48
Speaker
You know, when we first started doing this podcast together, I was still kind of fresh off by a few years that China Lake survey that I did where I really was starting to think about, you know, doing high resolution drone imagery, if not photogrammetry, but maybe even just high resolution video and then, you know, getting 100 percent survey coverage with that kind of machine because there's virtually no vegetation out there, no trees, nothing for the drone to run into. So you could really easily map out an area for it to look at and then have
00:22:16
Speaker
And then have originally, I was, you know, I was always thinking people actually just look at this looking for obvious things and then circling those and then archaeologists go out and ground truth them. But the obvious answer is there's so many sensors you can put on a drone these days. I mean, you can put lidar on a drone, you can put other types of imagery on a drone and then
00:22:36
Speaker
you know, take all this information in and man, you almost don't even need to be there. You just tell the drone, go out here, do this, feed that to the computer, and then have the computer send that to me at Starbucks, because that's where I'll be. And I'll go out and ground truth it. That's about what we're getting to. Yeah, we're not quite there yet, but it is going in that direction, definitely. I think that there's still a lot of work to be done on both ends of it. And
00:23:01
Speaker
I know you're a bigger fan of AI than I am, but one of the things that I've heard you say a lot about AI is how it feeds its outputs back in its inputs to get better. People are also really good at that too, at feeding data into things to get better models.
00:23:18
Speaker
I don't think it's an either or, basically. I don't think one thing is ever going to replace the other. But I think that in concert, the AI, the machine learning, the ground truthing, the remote sensing, all working together are going to get us in a very interesting place.
00:23:34
Speaker
Do you want to talk about this article some more? Hey, we probably should. Yeah, let's do that. Um, actually let's, uh, let's just take our final break and then we'll come back and talk about this. We don't have an ad for this, but we have been starting to get some, uh, some good traction for whatever reason. I don't know. I haven't do anything special, but arc podnet.com forward slash members. Uh, go check out that on the website because our last cultural share event will be up there shortly, probably tomorrow. Well, it will already be up there by the time you're hearing this. I'm not thinking fourth dimensionally.
00:24:03
Speaker
Anyway, it's my favorite quote from back in the future. Anyway, so we'll already be up, but members get access to those in the past. And we had a great one this last Sunday as we're recording this on underwater archeology. So it was a really fascinating discussion. So members can check that out. If you're not a member, arcpodnet.com forward slash members, we'll be back in a minute.
00:24:26
Speaker
Welcome back to the Archeotech podcast final segment of episode 208. Check out the article in the show notes if you haven't done so already because we're referring to lots of things in there. But yeah, getting back to the article, one of the things I thought was really cool and a very smart thing to do was Sean took these
00:24:42
Speaker
transects that he created these profiles off those transects and Amplified the topography because that's what the lidar is producing right? It's a topographic map essentially produced by lidar and he's amplifying this to really see that because some of the changes and Some of the variation the subtle variations in these could be extremely subtle until you really jack it up I do that in audio editing all the time sometimes if I'm having a trouble
00:25:04
Speaker
finding something because somebody's too quiet, I'll just take that segment and jack up the amplitude on it so I can really see what's going on there, delete what I need to, and then bring it back down. And it's an easy way to find small things. Yeah. And that's something that you'll often do with topographic imagery, like Hillshades.
00:25:22
Speaker
You'll make it so you know one meter in the vertical is now is represented as three meters or something So that you you really get the texture and you get the differences the otherwise you wouldn't see Just because the earth is a little flatter than you know, once you get up high enough, then you might expect Not everywhere, but lots of places and so they have to do that. I think
00:25:41
Speaker
with this particular technique. The problem with that is you can introduce a lot of noise. So he has a secondary part of how he smooths out the noise, and that's ingenious. He's smoothing out the noise both on any individual profile. So instead of having it be jaggy and a little lower and then jaggy up high, it smooths it out into a nice normalized curve, a nice flat bottom.
00:26:04
Speaker
normalized between one and the next one and averaging those so that you end up with a very idealized, but generated from real data profile of where that roadway is and what it actually looks like, what its cross section or its idealized cross section is. And along with that, I mean, that might not make sense, but I've got to highlight the figure three in this article is absolutely beautiful.
00:26:28
Speaker
because it conveys exactly what they're doing with that so succinctly and so attractively. If nothing else, just go take a look at the article for that because I think that is an Edward Tufti-worthy illustration of how to do a map and how to do a diagram.
00:26:45
Speaker
Nice. Yeah, it's fantastic. In fact, I was sitting on that and I was going to mention it when you brought that up because it is fantastic. Yeah. It's interesting, too, because we're not doing this just to make fancy graphs and maps. He's trying to figure out, you know, some information about these. What does it all mean? Right. So one of the things he mentions in the article is that his longitudinal profiles show how the road grade was modified in relationship to the nearby terrain. So how it's changed and really constructed in response to the nearby terrain. And then the transverse profiles or cross sections
00:27:15
Speaker
help obviously reveal depth, shape and character of the road bed, which I also thought was really interesting. Cause you know, it's interesting through time. As you look at those, how people use roads, are they walking in single file or the walking side by side? Is it a wide road because they're carrying lots of things or maybe even have some sort of, I don't know if they don't think they had carts or anything like that. They carried stuff on their heads. I don't know, but, uh, they didn't have wheels. They didn't have wheels. They're really good.
00:27:39
Speaker
Yeah, exactly. Exactly. They didn't construct wheels. Let's just put it that way. And if they had, they'd be very different roads. Like if you did this on a lot of early Roman roads, at least ones they didn't pave or put flagstones down or something like that in some way. Even those though, they have ruts in them that are predictable based on the things that were rolling over them. So yeah, it's really interesting. And this research can be used to
00:28:03
Speaker
expand into other areas like that and really is a foundation for that. Your comment about how the roads were used and how people
Cultural and Social Implications of Ancient Roads
00:28:11
Speaker
traverse them is actually part of the previous article that we interviewed him on here talking about moving logs and how people would have
00:28:20
Speaker
carried these things because you could carry a log side by side. You could carry a single file. You could have a couple people or you could have multiple people. You can drag it. All this stuff goes into questions of how he's looking at how these roadways were used. And this is yet then, I guess, another
00:28:36
Speaker
dataset to help understand that. It came up a little bit in our last interview two weeks ago, but trying to get at not just the tech of it for its own sake, and not just the numbers of things for their own sake, but also to try to get an understanding of how people did what they did, even the mundane tasks, moving a load of goods from one place to another, making a little bit of a tool.
00:29:03
Speaker
stuff that probably wouldn't have been recorded in any way, even if you have writing, but does tell you things about how people in the past lived. And so it's interesting just to try to suss it out. Yeah, and something along those lines too that he mentions, some people look at the stuff that archaeologists study and other sciences like this and they're going, okay, that's cool, but why? Why do we care, right?
00:29:26
Speaker
It's a stupid road that you went from one place to the next. Who cares about a road, right? We care about the things at the end of the roads. But one thing he, I think cleverly mentions is understanding how the road was constructed and its morphology and how that matches with, you know, some of the other roads around there really tells you a lot about the culture that was there, right? Because
00:29:45
Speaker
Is it a single line path that was just well-worn through time where people were going from one place to the next and that's just kind of haphazardly made almost like game trails because it's a path of least resistance between two places? Or did it start that way and then turned into something that was more constructed, which nobody's just going to widen and make and improve a road just because they want to. That's going to take some sort of
00:30:08
Speaker
you know, political or cultural will or even religious will in order to make this thing that's for the good of the people, that's going to help everybody. Again, people don't just go out and do that. They're usually told to do that and brought together by a person or a unifying body or a concept. And knowing how these roads were constructed can help start to get to some of those meanings, which I think is really cool. Yeah. And especially when you do have it in a complex society, you oftentimes will get other things like who can use the road?
00:30:37
Speaker
I don't know that that's been suggested in terms of these roads, but that is a legitimate question that you could ask of roadways anywhere. Is this a private road? Is this a toll road? Is this a private road of some kind? Is this something that anybody can access or is it just for cultural or political or religious or whatever elites to use?
00:30:58
Speaker
Or inversely, it's considered too gross for them and it's only for the lowest castes or whatever. There are lots of ways that you can slice and dice how you want to analyze these and try to get a better understanding through. Like you said, we tend to focus on what's on the end of the roads, but the roads themselves hold a lot of information themselves. I'll tell you what, there's some interesting carpool lanes here in the Seattle area going up 405 and up I-5, mostly 405 lanes.
00:31:27
Speaker
Yeah. No, listen to this. It's crazy because they've, they've done a really interesting thing that I haven't seen anywhere else in the country. And I've been in a lot of places. They've made the carpool lanes a toll lane and they're calling it a carpool lane slash express lane. So if you've got two or more people, you can use it. Yeah. If you got two or more people use it, you can use it for free. If you want to pay 75 cents to a dollar 25 and you're only one person, then you can also use it. Right. And you're sitting in traffic and you're just looking over there going, man, those people, they suck until you get over there. Then you feel like the elite.
00:31:58
Speaker
You feel like, I'm in it now. See you suckers. Anyway, but you're totally right. If somebody's going to go through the trouble of building and constructing and maintaining a road, there's a darn good chance that they're going to go and limit who could use that sometimes. Maybe they didn't though. Maybe it was made for everybody.
00:32:21
Speaker
You want some recognition for that effort a lot of times, whether that's, again, through political or religious, I guess, you know, some sort of gains that way or something else, who knows. But just studying the construction of these and really getting into it tells you a lot more than you would think you would know, you know, from just from not knowing because everybody studies the settlements out there, right? Pueblo Bonito has been studied to, you know, the last centimeter of rock there and
00:32:49
Speaker
and all the other little, you know, Choco and settlements within Choco Canyon, and then the Choco and outliers that are at the ends of these roads and along the roads. But yeah, how much, how much work has been done in between them to know the significance between different things? You know, if it's a really nice, good, well-maintained road, maybe that imbues a lot of significance, religious or otherwise, between those two end points. You know what I mean?
Episode Conclusion and Future Topics
00:33:13
Speaker
So.
00:33:15
Speaker
All right. Well, before we wrap up, one last thing I'd like to comment about this is that a couple of years ago when we talked about lidar, it was about the lidar itself. It was really whiz-bang. Cool. We can use it to find sites. We can use it to find features. We can use it to find different things. And it was all about finding. And here it's not
00:33:37
Speaker
This article is not about the finding. It's taken it one step further. It's like, OK, so this is yet another data set that we have. What can we do with that? Not just find the sites, not just find the roads, not just find the things, but how can we try to tease out additional knowledge from that? So again, like I said, this article is the evolution of his previous one. And the tool set is evolving as we're discussing it here on the podcast.
00:34:06
Speaker
Nice, nice. Well, I'd love to try to get Sean on. Sean, if you happen to be listening to this, you can contact Paul or I. You can get a hold of me and Chris at archaeologypodcastnetwork.com. All our contact info is on the website. If anybody knows Sean, wants to get a hold of him, I'll probably try to send him an email. Just been so busy, just didn't have a chance to really reach out. But that doesn't mean we can't come on and talk about some of the other stuff that either didn't make it to the article or really kind of flesh out some of this information.
00:34:33
Speaker
Any other thoughts on this, Paul, before we close out? No, I've got a whining dog under my desk here who really needs to go to the bathroom. So we can close this out. Nice. All right. Well, with that, we'll see you guys in two weeks. I don't know what we're going to talk about. Paul's in Saudi Arabia. He may or may not be here, but I'll figure something out. I'm going to try. I'm going to try. I hear you. I hear you. All right. Thanks, everybody. All right. Take care. Bye.
00:35:16
Speaker
Thanks for listening.
00:35:26
Speaker
This episode was produced by Chris Webster from his RV traveling the United States, Tristan Boyle in Scotland, DigTech LLC, Cultural Media, and the Archaeology Podcast Network, and was edited by Chris Webster. This has been a presentation of the Archaeology Podcast Network. Visit us on the web for show notes and other podcasts at www.archapodnet.com. Contact us at chris at archaeologypodcastnetwork.com.