00:00.00 connor Welcome back to episode none of a life in ruins podcast we are here with Dr Devin Pettigrew and we wanted to start off this section this section of ah we wanted to start off this segment of the podcast really focusing on. Experiment they did so we kind of characterized and talked about how they're they're summarizing other people's experiments and using their data to kind of at least start asking this question if Clovis points are very effective ah effective at at penetrating things. Um. But there obviously is None parts to this. So David do you mind explaining you know, kind of what they did what they did for their experiment um to kind of also test this efficiency of of Clovis points. 00:47.42 Devin Sure, yeah, basically they have they have a setup there in their lab that they've used for to ask a lot of different questions to perform a lot of different experiments and they have so the specifics of their setup is they have a £29 draw Compound Bow and it's mounted on a a mechanism that that will shoot it consistently called a spot. Hog Hoer Shooter I Believe um, any case that's what it's called. 02:38.22 connor Oh my God that allowed so. 02:04.42 Devin Yeah, yeah, that's the name of it I mean that's yeah, it's a product that's and that they've talked about in their papers I think it's funny anyway, but that's but that the nice thing about that is like um, it's it's as repeatable as you're going to get. 02:55.34 connor Are. 02:36.96 Devin None of the problems we have doing these controlled experiments is to meet this. We're trying to meet this like mythical scientific. You know ideal of having a repeatable experiment and no repeat. No experiment is actually like perfectly repeatable just because there are like all these subtle differences that occur. And you can never like do it exactly the same way every time. But for this that you know you can go buy the same bone. You can go buy the same thing that they're using. So so that is nice and a smart approach. Um, £29. 02:12.78 archpodnet So what's what was the draw strength on the bow that they used and what's the recommended hunt ah pound strength for hunting elk in Colorado. 03:59.80 Devin Ah, so they actually just removed the the recommended poundage but I think most compound bow hunters would tell you at least well most traditional bow hunters would tell you at least £55 of draw. And I think most compound bow hunters are going to be using something more like seventy eighty pounds of draw. Yeah, um, well because it results in a different arroweros speed. You know the the poundage of bow is it gives you a rough indicator of the aeros speed. 03:19.70 archpodnet And why is that important. 05:11.88 Devin People are going to say you know you need a hunt with at least a £55 drop out Well that could result in different arrow speeds depending on the specific material of the bow and the design of it. Whatever Yada ya there is but the goal is to get enough speed on an arrow with enough way in a. And efficient enough armature on it that it's going to penetrate the animal that you're after and kill that animal relatively quickly. 04:34.26 archpodnet And you as an experienced and successful hunter. What would you use a £28 bow for hunting. 06:19.90 Devin Well a £29 compound Bow you could probably Kill. You could probably feasibly go out hunt like small deer sized animals with that if you have really efficient are. Broadheads on there but ah obviously not an elephant and it yeah and I think probably you'd run into a lot of hunters that would tell you to use a heavier drop O as well. Even for runninging like you know little deer. So. 06:02.44 archpodnet Right? And even for ethical reasons Hunters want to be able to dispatch and harvest animals with the least amount of pain for an animal and use a lower draw strength that animal could suffer. So. 07:40.52 Devin Correct correct. Yeah, you're trying to get pass through shots that animal needs to drop as quickly as possible. Both for an ethical reason and so you can actually retrieve that animal. So. 08:53.40 connor Are are there any studies of like maybe parts of prehistoric bow Bose and like they're theoretical like draw weights they would have as part of that. 08:27.56 Devin Yeah I mean that and they range just like modern ethnographic or more recent ethernomographic bows. Um, they they range you know from the forty forty five pound range up to you know, seventy eighty pounds so yeah 07:34.62 archpodnet Fair enough. 09:05.92 Devin Ah, mostly what you're looking at there are are replicas of artifacts you replicate it and because you obviously can't draw like 1000 year old but you replicate it and then test the pound and so you're hoping to to your replicas close enough to tell you how that boat formed. 08:06.88 archpodnet Fair enough and so they're they're in a lab. They have a rig set up to fire a bow from the same position to try to control the experiment as much as possible. It has a draw strength of £29 what else is going on here. 10:00.74 Devin And they're shooting it into Clay I can't remember the the specific distance but it's pretty close something like five meters and their arrow weighed about seventy two grams and they're shooting these like I said these ground stone points into pottery clay and I I did mention that they tried to validate it. They they did ah an experiment where they had basically the the exact same setup and they took store bought meat just like these. Beef fros and like lined them up and shot those groundstone points through the meat and through the clay and they got similar penetration. Um, however, they also shot an arrow with a regular pointy field point on it. So there's just a round. Point you would shoot for Target and that penetrated deeper into the clay than into the meat and we're are also concerned here about how sharp their stone point actually was because like I said I wasn't napped. It was. Ground to shape on laprodary equipment to I think at least 60 grit lapidary equipment which is like a really rough grit potentially as high as 200 grit but I recently heard a podcast with Ed Ashby who's at Bow Hunter saying could ground a ground a broadhead with like None grit and that makes it pretty sharp but not as sharp as like if you drop it on leather so like 20200 grit I don't know so we don't we don't know how the point is we don't know how they compare in terms of their sharpness. To like a napped edge and if it was sharp. It might penetrate better into meat. Yeah. 12:16.40 archpodnet You got you? Okay, so so what's the issue with using clay and and you know as an extension to that like are there also issues using Ballistics gel which is another common target. 14:19.30 Devin Yeah, and there's a there quite a few of the experiments they put in their table use Ballistics Gelaton So this is something I looked at really closely and there was a past experiment that did shoot crossbow vaults and arrows into ballistic soap which is used. 12:54.60 archpodnet Material and. 14:58.94 Devin Commonly in Europe ballistics gelatin and fresh pig carcasses and but basically there's 2 really big issues with the ballistics gelton the none being that in this experiment they just like in the erran. Actually the lead author is key key Aaron and others experiment shooting groundstone points in the clay and in the meat as well as field points in the clay and in the meat in this experiment they found that field points penetrate deeper into those target simulants. Field point penetrates deeper in a ballistic so deeper in the gelatin and a lot more shallowly into the pig carses so it would penetrate like 40% um, as deeply or less deeply into the. Into the actual carcasses than it would in voice None gelaton when they shot broadheads into those targets. They got the opposite results so that the broadheads actually penetrate a lot more deeply through the pig carcases. Then into ballistics gela term or ballistics. So and so what that tells us is that those None target stimulants are not scalable to flesh. They're supposed to be flesh stimuluss meaning that they they scale to flesh so this brings up the None problem. Which is that firearms research has for years studied target simulants and found one that works for bullets that being widely accepted None ordinance collagen-based Ballistics Gelaton so basically to make that you're going to take a pig or you know cows when you butch them. You're going to take parts of those animals that you that you know you don't save for the grocery store tendons bones hide those get processed. Really extensively in a factory with a lot of pipes and hot water acid extraction and you end up with like pure collagen protein. That's what you're using for the gel but you have to use the right amount of it. It's not that you can just it's not that there's just like a thing out there called collagen protein and it's. Like flush. Ah you have to mix it just right? So you get 10% of that mixed with distilled water. You mix it all up just right following all the proper protocols you cool it just right and you know just to the right temperature which is °c pull that out. 20:31.80 Devin And then you have to calibrate it and there's a ah protocol for calibrating it once you've done that then you can actually test it and then you're going to get similar penetration depth for bullets into that material as into flesh as the pig flesh. Pig muscle right? That's what I mean by flashes muscle plus like some gris and stuff in there. Flesh um, so so that material has been determined to be scalable what we're seeing basically is that ballistics gelatin. Even though it works for bullets. Bullets are very different from from arrows and and arrows travel at much lower velocities. They have like a sharp cutting edge. We expect the sharpness to do something so those aren't materials aren't scalable for the the projectiles we're we're trying to study. And just to summarize the results quickly I've got doug and I have a paper that will be available as a preprint at least when this podcast though but I can summarize quickly. We shot broadheads with there were. Same size same shape same way one very sharp None extremely dull into ballistics gelatin this was actually a synthetic version of Ballistic Shelton and in the pottery clay and in both instances there's no difference in the penetration depth. Also shot arrows with broadheads field points. So these are target points and then blunt points and unsurprisingly the blunt point bounces off the places gelaton however, the blunt point penetrated about fifty centimeters into the clay target whereas the broadhead penetrated about seventeen centimeters into the clay target the same broadhead on the same arrow at the same velocity penetrated almost eighty centimeters through bison. So it's another example. Of how these 2 target materials aren't telling us what we think they are you know archaeologists and not. We've never gone through the extensive experimental regime. You know all the research that we need to do to ensure that these target media are scalable. They are showing us what we presume they them to be showing us. We've never done that you know where compare our work to firearm terminal ballisticians and it's just like I don't know we're our kids playing into sandbox. It's kind of ridiculous. Yeah. 24:47.86 archpodnet With a baby gun just like completely outclassed right? And and I think that's ah, a larger issue in the field professional archeology where where we are kind of these copycat scientists where we we took this idea of what is science without really testing. 26:22.32 Devin Yeah. 26:32.58 Devin Yeah. 25:22.32 archpodnet I mean I mean part of being an archeologist and anthropologist is we rely on other folks' expertise and we try to apply it to our own work and and clearly what you're saying is that it's not necessarily analogous that we need to actually look at like yes, there's Ballistics Gelatin that works specifically for firearms. And we haven't tested that applicability to um, ah weapons that humans have used throughout the course of of time prior to to firearms. Um, which I mean that's that's alarming right? We have a whole table in this paper that uses all these different materials. 27:37.80 Devin Yeah. 27:48.94 Devin Yes. 26:34.54 archpodnet And what you're saying is like actually using carcasses is is is the best analogy because the the clay in the ballistics gel. There's so much variability in making ballistics gel um that one that's problematic. 28:22.66 Devin Yeah, and archeologists don't ever talk We we never talk about that frequently. We just say we have Bliss Shelter who. 27:09.24 archpodnet Yeah, so we just need the s day. We just need the ses to to purchase a Bison Farm specifically for experimental purposes right? um. 28:51.40 Devin Yeah, yes. 29:45.98 connor Ah, but ah, but there's also there's no not saying that we couldn't find a ballistics gel mix alternative that works for arrows and whatnot. It's just we haven't done the research deep into we haven't done the we haven't done the bullet research Essentially where people are. 29:29.54 Devin So right? So you won't find Blissistics Gelaton um I think this is part of the the point is it just it's the nature of the material blissistics Gelaton and Clay or just whatever formula you find. 30:21.76 connor Doing there. 30:05.90 Devin Those materials isn't going to work and Clay is extremely problematic as well because it's very hard to to control. Ah how it's formulated when you go buy Clay when I went by Clay to test they're like which kind. Do you want? we have over 30 different. Varieties and they're all different and I'm thinking okay in the original paper. They only said we had a low fired Pottery Clay you know they're not really going into any depth and about what those clays are made of and they can't because the potter isn't going to tell you specifically what goes into that Clay. It's like ah, a recipe for. You know it's like Grandma's recipe you got to protect that recipe. So so it's impossible to repeat it. Um, yeah, so but but those materials aren't going to work. We got to find something different and what I proposed what I looked at was. Forensic studies of knife knife stabbings forensicists are pretty deeply interested in like how humans murder each other with various things including knives and they've tested that because it's actually useful to to know like how efficient is this knife versus this knife because. You may be looking at a criminal case where you've got you know? ah None possible murderers. None ne's ah you know a five foot tall petite female and the other's like a six foot tall dude and and based on like the the angle of stabbing and the force necessary. That that could be important but how they how they test those knives is they use skin stimulants because skin is the most resistive soft tissue on the body. So and it's the none barrier you have to penetrate. It's understandable skin is what protects us our skin protects us from the outside world. And it protects us from projectiles and things like that none you got to get through skin and you have to get through clothing so they're testing the efficiency with which knives penetrate through skin and then that gives them a way to compare different knife designs and that's essentially what we're trying to do in this controlled experiments of skin. Compare these different designs. A lot of times what these folks are trying to do is look at overall penetration depth and for that it's the the problem here is that we want to know how analogous this experiment is right? Um. We're trying to know how these points and these weapons that the points are attached to would perform killing mammoths. So then we need to account for the thickness and resistivity of the skin of the mammoth the muscle underlying it. 35:46.58 Devin How deep is the body cavity all these factors that are particular to mammoths. Ah, so that's the kind of target. Unfortunately we need we need a target that tells us you know more about what mammoths are like you can't yeah a reindeer is different and a dog. Were some early experiments on dogs. They were dead. Everybody's going to be upset about that. All these animals were dead that were used in the cars experiments but you know none of them in the table or are elephants or Mamma yeah, but. 37:39.60 connor So if they like ah bring back mammoths and they can breed them. Ah if they can bring back mammoths or like you know, get them semi out of extinction with something like that. You'd be interested in participating with stabbing them if possible. 37:01.90 Devin Clearly man. Sorry. 37:22.10 Devin Oh my God The yeah yeah, but the media fall I would be here in is can you imagine? um I mean even no one's dead beforehand people just don't like this stuff. Let's be honest, that's part of the issue we're running into is people don't like. 36:12.60 archpodnet Yeah, but but real quick. So like because we were yeah right. 38:00.86 Devin You have an animal that's dead. Even if you're going to eat it afterwards. People don't like you. 36:41.58 archpodnet Right? So based on the the design of this experiment the low poundage of the bow typical to what would be recommended for hunting something big. What we consider big game today which is elk which is still much smaller than an elephant which is not necessarily analogous to ah to a mammoth. Um. And the kind of target that they used would you based on your professional opinion. You know would you do do you think that these the results they came up with are are accurate. 39:17.90 Devin Yeah, or meaningful. Yeah, no and again, let's think about the target media. Um, if you use Syntheticlisistics Gelton like I did you're gonna get. 37:57.60 archpodnet Or meaningful. Yeah, so. 39:54.82 Devin Very shallow penetration. Um, and in fact, there's they they cite. Ah one of my favorite experiments article by wood and Fitzhugh where they shot different kinds of points a near a reindeer and then into synthetic ballistics shelton I find that. Their experiment really useful but they calculated they had None different point types obidian bone with an edge and then bone with obsidian glued along the edge and the points that penetrated the absolute best. The obsidian the napped obsidian points to the reindeer and the points that penetrated the absolute worst with the napped obsidian points in the ballistics glton so what we need to do is take out if we want to know how those points penetrate we perform against reindeer at the given values of. You know kinetic energy momentum. We need to none remove all those shots with ballsistics shelter. Okay, that material may tell something about something I don't know what at this point so there's that problem and this you know problem. Carries over to clay and then in terms of the lightweight be Carlton you were mentioning. They shot a light poundage or or ah, a low weightight dart an arrow basically that mimicked like a really small halfletal dart. Weighed about seventy two grams they're really small like basket maker darts I was talking about at the none were that we threw at the pig those weigh about Ninety Grams or so so even what I would consider like a really small atlo dart. Their arrow was wider than that. Um, but they did get it to. Ah, little dark velocities. The result was that it carried about 35 joules of energy and there was another extremely useful article compiled by Tomka Steve Tomka about endurance of ale and dark weaponry after the poe and he he compiled all these recommended values of momentum and kinetic energy for hunting animals of different size and the lowest kinetic energy you want for an animal as big as a bison or or bigger. Is eighty eight joules of energy so they were they had an arrow of about 35 joules of energy penetrating into clay. so so I think the result is that um, we just don't know what those results mean right. 45:22.76 Devin But don't know how to use them. 43:59.42 archpodnet And fair enough and on that note we do know we need to close out this segment so we'll be right back with episode one 12 with Dr Devin Pettigrew right after these messages.