Download 1 Anthropology Taphonomic Signature of Animal Scavenging

Anthropology
Taphonomic Signature of Animal Scavenging
Hi, everybody. I'm going to talk to you today just a little bit about my thesis which can almost be summed up pretty simply as when something dies in the woods, other things come and eat it. 1
Anthropology
Taphonomic Signature of Animal Scavenging
So this is your teaser picture because I have a lot more, but I'm going to have to give you a little bit of background and data before we can get into the fun part for the last 20 to 30 minutes. 2
Anthropology
Taphonomic Signature of Animal Scavenging
So essentially, when we find any sort of site or specifically bones out in the woods, we actually have to ask ourselves, "What could have potentially happened to these bones to make them appear the way they do today?" And that process or that study is called taphonomy, and taphonomy is essentially anything and everything that happens to an organism from the point that it dies until the point of discovery. So this can be you know hours or months or thousands of years depending on what you're looking at. 3
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Taphonomic Signature of Animal Scavenging
And there are a couple of specific taphonomic forces that we can group everything into. There's weathering which is things like the sun or wind and rain affecting bone. Plant growth will also damage bone as will soil, pH, flowing water, and what we're really going to focus on today is what animals do to bones. 4
Anthropology
Taphonomic Signature of Animal Scavenging
Now scavenging of bones, itself, by animals results in a couple of really specific things. Animal scavenging represents one of the greatest contributors to the destruction of human remains. Scavenging results in high rates of damage including loss of soft tissues, modification to bone, and disarticulation and scattering of elements. The ability to differentiate animal induced damage to bone from human induced trauma or post mortem alteration is important for accurate interpretation of forensic anthropological cases. Involvement of animal scavengers results in the scattering of remains which in turn affects the degree of element recovery. A better understanding of the role of scavengers and their behavior may result in higher element recovery rates. 5
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Taphonomic Signature of Animal Scavenging
Now, there are two major classes of scavengers. We can divide everything between carnivores and rodents because they damage bones in different ways.
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Taphonomic Signature of Animal Scavenging
Carnivores in effect, will induce pits, punctures, scoring, and furrows onto the bones which you can see with the arrow; these nice little pits and here's some more pits and some of the scoring on the sides. If you think about it it's like if you give your dog a rawhide or a bone, they're going to sit out there and chew on the ends, consume part of it causing noticeable damage so it's not going to look how you would think it would if it was a complete unaltered element. 7
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Taphonomic Signature of Animal Scavenging
Rodents, on the other hand, leave very different marks on the bones and that's really due to their teeth. Now rodent incisors grow their entire lives so what they have to do is constantly gnaw on things to keep their incisors an appropriate length, like if you've ever had a pet hamster or a class hamster, you always have to make sure to keep something in the cage for them to chew on and if rodents can get bone, they love to gnaw on it. 8
Anthropology
Taphonomic Signature of Animal Scavenging
So what this is just showing as you can see the nice parallel striations that the rodents teeth will leave on the bone, which I have some example of here. You can see here on this mandible, this scoring right here. This is a pretty severe case on a skull and here's the picture of a rat actively chewing on an ankle, essentially. So we can tell pretty simply the difference between rodent gnawing on bone and the damage that carnivores tend to leave.
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Taphonomic Signature of Animal Scavenging
Now previous research with scavenging was kind of a little studied area in forensic taphonomy, although, there's a rich history of scavenging research in paleotaphonomy, so looking at the fossil record. Now previous studies have generally focused on field or laboratory based experiments, retrospective case reviews, on individual case reports. However, little attention has been devoted to a more detailed study of postmortem damage created by animal scavengers and larger forensic collections. Many of these studies also focus on small to medium‐sized mammals such as dogs and coyotes or carrion feeing birds. Little research has been conducted with regard to large‐bodied scavengers.
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Historically much taphonomic research is focused on decomposition rates; however, these studies are often conducted where climate and insect activity are the only factors considered in decomposition. These experiments, though important, do not reflect the conditions that many remains are exposed to especially in Northern California. The presence of animal scavengers can dramatically affect decomposition rates especially in the early stages where insects are most active. If all the tissue is consumed before insects have time to utilize the carcass, decomposition rates will be drastically affected. Previous scavenging studies that have dealt with time since death estimations often focused on the skeletal disarticulation sequence as the main indicator of time since death. However, there are many complex regional and control systems tact specific factors that influence decomposition and disarticulation rates as well as scavenging behavior.
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Taphonomic Signature of Animal Scavenging
Now the State of California represents a wide array of habitats with enormous diversity in the flora and fauna. Northern California, which I'm defining as San Francisco Bay area north, native Californian's can argue with me about that later, but that's what I'm going to call native Northern California for this. But Northern California includes habitats such as Riverine, Riparian, Alpine, Tule Marsh, the Great Basin, the Eastern Sierra Woodland, and the Redwood Forest of the North Coast Range. Now this poses a unique problem with regards to the decomposition of human remains in outdoor contacts. Large amounts of rural and undeveloped land provide a habitat for a multitude of scavengers that will actively utilize human remains as a food source. A majority of locations submitted to the CSU‐Chico Human Identification Lab derived from outdoor contacts and thus often show substantial evidence of scavenging.
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The diversity of fauna results in a wide range of carnivorous mammals. Common carnivores include the Black Bear, Western Spotted Skunk, Grey Fox, coyote, raccoon, as well as domestic pets. Now although the Black Bear and raccoon are omnivorous, they're known to actively scavenge animal carcasses and are treated as carnivores for the purpose of this study. 13
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The common scavengers include the bobcat, mountain lion, martin, fisher, and badger. Mountain lions excepted, these carnivores are thought to minimally contribute to the scavenging of human remains.
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Northern California also supports a diversity of rodents including the California Ground Squirrel, brush mouse, Pinyon Mouse, and California Kangaroo Rat, to name a few. There's lots and lots of rodents.
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Now, the goals of my study are kind of in three major parts. First, I wanted to do an analysis of the inter and intra element patterning of post mortem modifications on human remains caused by the animal scavengers so I wanted to see is there any sort of specific pattern that I can gather both within a single element and from skeletal element to skeletal element. Then I also conducted a metric analysis of the canine impact damage in relation to carnivore tooth dimensions. So I'm trying to see can I correlate that puncture damage mark on the bone with the tooth of a specific species of animals to say who may have caused this damage and what else can that tell us about what happened. So then I wanted to apply that model in an actualistic experiment to see can I reproduce these patterns and actually look at what happens in an open natural environmental setting with large scavengers.
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So what I did is I examined 21 cases involving animal scavenging submitted to our human identification lab between 1986 and 2008. A majority of the cases, 16, are curated here while the remaining five were examined through previous case reports submitted by Dr. Bartelink. 17
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The cases derived from 12 Northern California counties represented by the red dots on the map. One case from Nevada was included in the study due to similarities in habitat with Northern California. All cases are derived from outdoor contacts. The five retrospective cases are excluded from the tooth impact statistical analysis as the remains were not present at the time to actually measure those impact marks.
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So for each case, I conducted a detail inventory. An element was counted present if any portion of the bone was identified. Only elements with scavenging related damage were examined in detail. Diagrams were used to record the completeness of each element as seen in the diagram to the right. Appendicular long bones, so the bones of your arms and legs were divided into equal thirds, representing the proximal middle and distal portions of the element. And all other elements were divided into equal medial, lateral, and middle portions. Missing portions of elements were attributed to scavenging only if the border showed evidence of scalloping, pits, or punctures.
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So then the percentage of bone missing due to scavenging was also recorded for all appendicular elements on an ordinal scale as a measure of scavenging intensity. The same diagrams were used to record the distribution of pits and punctures. Now the absence of an element was not assumed to be the result of scavenging for the purpose of this study. If I didn't have it, there's no way that I could say that it was because of a scavenger because there's too many other things that could have contributed to that element not being present at the time that I was doing this study. 20
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So for my study, I defined pits as an impact mark less than 1 millimeter in depth with a circular shape and a puncture was defined as an impact mark greater than 1 millimeter in depth with a circular to irregular shape. Scores and furrows were recorded but were not included in this study. The parallel striated of rodent gnawing was also recorded, but I didn't investigate any further due to the minimal scavenging by rodents in the sample. It was really carnivores that were the main contributors.
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Scalloped edges were defined as margins with a rough edge often including semi‐circular impressions seen in the picture to the top. Spiral fractures were also included as signs of scavenging activity in conjunction with other scavenging indicators. Spiral fractures were defined as a fracture that is curved in a helical, partly helical, or completely helical pattern around the circumference of the shaft. Now spiral fractures are generally caused when a large scavenger applies force in the form of levering, biting, and pulling on the remains. The second phase of this research attempted to identify size, class differences between species associated with the tooth impact damage. I used digital calipers to measure the maximum diameter of all the pits and punctures on the bone. I tried to record as the nearest tenth of a millimeter and I also recorded their anatomical position on the diagrams.
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In addition, I took dental measurements from the canine teeth of the following species from our zoological archaeology comparative collection: Grey fox, raccoon, bobcat, Mountain Lion, coyote, and Black Bear. I chose these because they are among the common scavenger species in Northern California, and these specific specimens were chosen based on completeness of maxillary and mandibular canines, and they were all collected from locations within Northern California. The maximum diameter of the canine tip, the maximum labial lingual crown diameter, and maximum mesial distal crown diameter were recorded, so I took the tip and then the maximum width at the base of the tooth. Now the maximum labial lingual diameters were excluded because the mesial distal diameter actually represented the maximal width of the tooth, so that's what I wanted, maximum width at the top and maximum width at the bottom of the tooth.
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So now for some results so we can get to these fun pictures pretty soon. [Chuckles] Okay. This damaging intensity for each portion of an element was totaled. The average seen here are those totals divided by the total possible ranking score for all present portions of that element. This slide shows the top 10 most intensely scavenged elements which include the pubis, ischium, and proximal and distal segments of long bones. Now the pelvis, aside, it becomes evident that the proximal segments of the long bones, the ones that are further up, are more intensely scavenged than the distal segments of the long bones. 24
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This gigantic table shows the percent of representation of each element or body region and also the percent of available elements that showed evidence of carnivore and rodent scavenging. Larger anatomical portions such as the cranium, femur, and innominate are represented more than 80% of the time. Whereas smaller elements such as the patella, and the foot and hand elements are among the least represented with less than 50%. Approximately 50% of all elements examined showed evidence of animal scavenging, 98% of which were affected by carnivores, and 7.5% by rodents. Carnivore tooth impact marks were most common on the hands, ribs, and lower limb elements and are rarely observed in the vertebra, sternum, or in the skull. 25
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Rank order comparison of the percent representation of an element and it's frequency of scavenging were not statistically significant. This suggests the differential recovery of remains may largely account for the variation in the representation of elements. Because many of the cases included in this data set were recovered by law enforcement with minimal archaeological and osteological training, the representation of elements may be more informative of the recognizability and size of skeletal elements than element survivorship itself. 26
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This table and diagram represent the total average scores for all element positions ranked on scavenging intensity. There's a high degree of variation between the proximal and distal portions of several elements such as the humerus, femur, and tibia. One hundred percent of elements have a mid shaft ring of less than 10%, so the middle portion of the bone is being scavenged less often than either of the ends of the bones. These results indicate that the elements must be viewed as part of the skeletal and muscular system as a whole rather than as an isolated element portion because when the body is actually articulated together, you have to think about how let's say the humerus is actually connected to the ulna and the radius at that time, versus thinking of them as separate bones. And this is going to be the subject of some future ongoing research.
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As for the tooth impact mark portion of the study, the figure on the left here is a box‐and‐
whisker plot showing the distribution of the maximum tip and the maximum mesial distal canine diameters for the various carnivore species that I've examined. And there's just minimal overlap between the two. Now for the study, I assumed that the pits will be more strongly correlated with the canine tip diameter since they're shallower, whereas the larger punctures will be more strongly correlated with the maximum mesial distal diameter. My reasoning being that the tooth would have had to have penetrated further down into the bone to make the deeper pit so it's going to be correlated with the bottom of the tooth. The plot on the right shows the distribution of pits and puncture diameters recorded on the CSU‐CHILL collection. Comparisons of pits versus punctures indicate a high degree of overlap. Note the outliers, these portions on both the pits and the punctures. Now large carnivores are expected to produce larger pits and puncture diameters which may account for some of this variation. Alternatively, because many of the outliers are on the inominance, density may also be a factor in pit and puncture dimensions. For example, a carnivore can produce large tooth impact marks on less dense element portions composed primarily of cancellous bone than in the more dense thick cortical areas of the long bone diathesis.
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The pits had a mean diameter of 2.22 millimeters and punctures a mean diameter of 3.8 millimeters, a statistically significant difference. This suggests that for the data set, pits can 2 degree be distinguished from puncture tooth marks regardless of the carnivore species involved. A sectioning point was created to examine metric classifications of pits versus punctures. The sectioning point is 3.1 millimeters with cases below the value classified as pits and those above the value classified as punctures. Correct classification was achieved in 63.3% of cases for pits, but 85.8% of cases for punctures. Less punctures were more likely to be classified as pits based on the diameter than vice versa. The low classification rate is likely the result of scavenging activity of both medium and large size carnivores as smaller scavengers will have punctures that are smaller in diameter than the pits created by large‐size carnivores such as bears and Mountain Lions. But I'm also going to have to take into account size variation within the species such as if you have a juvenile bear versus a full‐grown bear; they're going to have different tooth sizes which would create different tooth impact marks even though they are the same species.
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Now this slide compares the mean pit versus puncture diameter by an element for the innominate femur, sacrum, humerus, and tibia. These elements had sufficient sample sizes for comparison and are ranged from greatest to smallest difference between pit and puncture diameters. With the exception of the humerus, significant differences between pit and puncture diameters are found for each element. Although bone density differences cannot be robustly evaluated with the present data set, the greatest mean differences occur for the innominate followed by the femur, sacrum, and tibia. Puncture diameter showed higher standard deviations than pit diameters with the greatest variation found for the innominate followed by the sacrum, femur, and tibia. This suggests that less dense, less cancellous elements such as the innominate and sacrum are more likely to show greater variability in puncture dimensions associated with animal scavenging behavior. 30
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The above figure shows the maximum canine tip measurements for both the maxilla and mandible of each scavenger species and the bottom row represents all of the pit marks on my sample. A majority of the pits cluster in the small animal range which is the Grey Fox, raccoon, and bobcat, and coyote, while the larger outlier pits are falling within the range of the large animals, of the bear and the mountain lion.
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This diagram shows the maximum mesial distal diameter for both the maxilla and the mandible of each scavenger species. The bottom row represents the puncture marks on my sample. All punctures cluster in the small animal range. The lack of punctures in the large mammal range may be due to several factors. Tooth impacts may never reach the maximum mesial distal portion of the canine, but may represent any point along the circumference of that tooth. Tooth impact marks may also have been produced by the carnassial teeth which are essentially the molars in most carnivores rather than the canines. An individual animal's bite force potential also influences the size and depth of the punctures. So the ability to associate tooth diameter with impact marks of specific species is greatly hindered by a number of factors. 32
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But if we look at an individual case versus the entire sample we get something just a little bit different. So this slide shows the distribution of pits and punctures in a single forensic case from the sample. Note that the mean pit diameter is 2.23 millimeters whereas the mean puncture diameter is 3.62 millimeters with no overlap. 33
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Now if we compare that with the small and large animal canine tip diameters and the pit diameters from the case study, we note that the pit diameters overlap only with the small animal range.
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Now this slide is showing the small and large animal mesial distal diameters and the punctures from this case study. Now there's a small degree of overlap in the mesial distal diameters of the small and large carnivores. But the human values show a very narrow distribution which is closer to the small animal mesial distal diameters than that of the large carnivores. So what I believe is in this case that you can say that it's more likely that a small animal interacted with this case than a large animal based on the pit and puncture measures.
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So to sum this part up, the analysis of inter and intra elements scavenging patterns indicates that there's a significant variation in the distribution of scavenging damage. For example, intensity of scavenging was more directed at cancellous rich bone portions such as the pubis and ischium, closely followed by the more proximal segments of several appendicular elements. Distal appendicular elements of both the upper and lower limbs are less intensely scavenged. Carnivore tooth impact marks are more common on the hands, ribs, and lower limb elements and rarely observed on the vertebra, sternum, and skull. Inter and intra elements scavenging patterns will need to be evaluated within the greater context of joint complexes and the overlying tissue. When animal scavengers are present, behavior is going to be directed at consumption of soft tissue primarily. Additional bone destruction may result from the scavenging of soft tissue initially, but in the long term of the secondary scavenging of the elements themselves. And I need to keep in mind that the overall element representation may be more indicative of their recovery effort than the actual scavenging itself.
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Now, as for the analysis of the pit and puncture diameters, this indicates that in some cases it may be possible to distinguish damage caused by small versus large carnivores. The data suggests that the pit and puncture diameters need to be evaluated on a case by case basis, taking into account the distribution of available scavenger species in the area and the specific environmental context. The differentiation of small versus large carnivore scavenging on remains is important because it aids in distinguishing taphonomic events from possible perimortem trauma. Additionally, understanding animal behavior key scavenger species may aid in the higher recovery rates at outdoor scenes.
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So to test this I did some actualistic experiments in conjunction with the Big Chico Creek Ecological Reserve. 38
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The reserve, in case you guys don't know, is owned by the university. It's approximately 4,000 acres and is host to over 600 plant species and 140 different wildlife species. And just to give you a general idea of where it is, where upper Bidwell Park ends is where part of the reserve begins. And I was lucky enough to get a very generous grant from the reserve which allowed me to do this portion of my study. So what I did and here's the part I know you guys were all waiting for is I got five pig carcasses. 39
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I don't have enough time to go into the long drawn out drama of the 2 years it took me to get these pig carcasses, but I finally got them on November 1st, and pigs are generally used in forensic context as analogues for humans. So what I did is I put them out in the woods at the reserve almost equally spaced out over the five sites over the reserve and to prevent immediate removal by the scavengers, they were each tied with some wire to rebar that was impounded into the ground. 40
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Each pig was monitored by a motion sensitive trail camera so whenever‐‐there's a little laser that comes out from the camera whenever something moves in the path of the laser, it takes a picture. So that's how I was able to say if I can get a picture of the animal actively scavenging, I can say I know that animal caused that damage so then maybe I can correlate that type of damage back to the human remains that we have in the lab. So now's the fun part where I get to share some of the pictures from the beginning of November. Okay. So I have lots of pictures and we don't have a lot of time. So what I'm going to do is take you through the two kind of most interesting sites out of the five. And I apologize for having to go back from folder to folder but putting them in one folder just wasn't working for me. 41
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So essentially what you're going to see [laughter], sometimes they're going to look like they're black and white because that just means there wasn't enough of a light source to get a color picture, but this is us setting up the pig on day one. And down at the bottom is [laughter] a temperature, the moon phase, the date, and the time. Now the first day, absolutely nothing came and investigated the pig.
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All the pictures are just of us setting it up and you can see here‐‐he's still there. He's been out there for a day. Nothing has come and investigated him. Lots of nice pictures of the pig. ‐How big are those pigs? ‐About 100 pounds was the best I could get.
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However, it's on the second night that things get kind of interesting and you'll see, here's the pig. 44
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He's going to remain there through most of these pictures and you can see the rebar. And here we've got the mother and her cub. Which end up seeming very thankful for the tasty treat I left out for them. 45
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You can see she's pulling on it. They've kind of ripped open a little bit right here. 46
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They like to come up and investigate the camera or chew on the camera boxes so every now and then you're going to see a nice close‐up of some fur or eyes and then it might be fuzzy for the next few pictures as they like to lick the camera too. So we got lots of bear tongue imprints, but you can see here at this point, they've kind of pulled away the skin down on this limb and the little guy is concentrating up near the head. Most of the pictures are going to be in black and white because they do seem to be more active at night.
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And I guess I did forget to say at beginning that some people might consider some of these images just a little bit graphic. I do have some close‐up pictures of the remains once I went and checked them so sorry, Netty. I forgot to say that at the beginning. I set the camera up to take two pictures every time that the laser was broken, but there's a minute delay between pictures. That's just the nature of the camera. 49
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Okay. So then, we get there the next day. And this is what the pig looked like when I got there. Skeletally, every single bone is still there, but they've kind of concentrated on the hind quarters, and up here on one of the shoulder joints. 50
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So now we're to night two. And what I didn't mention, what you see me doing here is, I was graciously allowed to use the brand‐new Trimble that‐‐nice, wonderful‐‐I love it. I spent the UPS unit that the department just got, so I'm taking GPS points of the rebar and the cameras, my datums for each site and then as the bones get scattered, I took point for each of those too. 52
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Okay. So now, you'll notice he shows up at about 2, luckily a couple hours after I left. And then the pig is gone. The wire and rebar did not hold those pigs down there for very long. When I did a pilot study with a deer, they didn't try to pull the deer our of the rebar; it just stayed there for three days, but they really I think enjoyed the fact that I gave them these nice 100 pound pigs to enjoy because they got it off every single site. So you can notice that this is a completely different bear. Then we get there. And I'm thinking, well, this is wonderful. I have this activity, but where did my pig go. And it took us an hour to find it. 53
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That bear was very determined. He actually drug it about 200 meters down a drainage ditch, up the other side of the drainage ditch, and left it in probably the biggest poison oak stand that I've ever seen. But it's a little blurry. Essentially, this is just intestines, and some vertebrae.
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So here is some vertebrae and some ribs and you've got all the major internal organs. They left those a lot of the times and ate them last. 55
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The skin seemed to go first and then they went for tissue and that really surprised me that they would leave those organs there when that was the first thing they went for on the deer carcass that I put out. 56
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Here's his head. They got the legs off in one unit most of the time, so it's scattered. At this point, I am still missing one arm and one leg, but everything else is there.
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So we moved the camera to try to be able to see if the bears would come back this night. So there's the first bear, but you'll see that they do go behind that rock too, and that's what they're going for. 58
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You notice we're going to get several different bears coming today. The little dark guy is back. 59
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I think this is the same mom and her cub that had showed up the night before, two nights before, but I'm not a bear expert. I'm just going by general looks. If someone wants to help identify bears, that's fine.
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This is what we ended up finding that next day. Nothing but itty bitty little fragments that are probably even hard to see. Here's a piece of a rib. 61
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Here I've collected a couple of the fragments that I could find. I left this site with a handful of bones compared to what was there the day before.
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And this is two more pieces of the mandible. 63
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Okay, so now I want to show you guys site three which was the other interesting site. So you can see, here's the pig here with the rebar and this was the only carcass that got investigated the first night. So this is the very first day, a couple hours after we out it out. He's pretty big. I was like he's blocking my entire view of the pig. 64
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Then the pig was gone. 65
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Yeah, so this is where the pig was. You can see here is one of the rebar pieces. Once again, I had some good helpers out. 66
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It was about 50 meters upslope from where it had been when we found it. 67
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This is the head.
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The rest of the carcass was lodged up against this fallen log right here.
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And as you can see, he ate almost all of the skin off, but skeletally everything else was still pretty much there. 71
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So at this point, since there wasn't enough of the carcass left, we retied it down with wire and then resunk the rebar stakes.
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What I'm pointing at is a nice puncture mark right there from a tooth probably.
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So it's kind of hard to see, but right here are the two rebars and the carcass is right here. 74
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He's got something in his mouth. 76
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So he leaves and a different bear comes and he's pretty big. 77
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Apparently eating this much pork makes them very tired as you'll see. I've got the next about 100 pictures are of him sleeping in front of the camera. Which is quite adorable. 78
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And now my favorite picture that I got; that's the pigs head. 81
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He's pretty big from what I can tell and he just stayed on that carcass the entire night. He was the only one that didn't really seem to mind the camera. At site five, that bear hated the camera. He chewed on the box. He knocked it down off the tree and took a big poop right next to it. I don't know why he hated the camera so much but he really hated it. 82
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I haven't gone through all of the Trimble data yet, but there was commonality where they all went upslope. This one didn't move too much. This is probably only about 30 meters upslope. One of them was probably easily 200 meters.
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Anthropology
Taphonomic Signature of Animal Scavenging
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Anthropology
Taphonomic Signature of Animal Scavenging
These are ravens and these were the first birds that I actually did get on site. The bear wasn’t too happy. He left and now there's nothing but birds and birds. And what they're on right now is the vertebral column, the innominate, or the pelvis that are right here. That's a little hard to see. 85
Anthropology
Taphonomic Signature of Animal Scavenging
Essentially, after I took these pictures, I went back the next day, and every single bone is gone. I couldn't find a single thing. The next day, I managed to find one leg and the day after that when I had a couple people helping me, very kindly of them at 8 a.m. on a Saturday, we did 10 meter transects, probably at least for 100 meters in either direction from the carcass and still only found the mandible. I'm still missing most of this pig. It's my mystery pig. I don't know where it went. I've looked for days. I'll probably go back out and look one more time, but I don't know if the bear carried it off, if it was a whole pack of squirrels that came and got it. [Laughter] I don't know, but it's all gone and it's kind of frustrating because I know that there's some great damage on these bones. Pigs one, three, four, and five have all had scavenging activity. Mostly bears. Pig four, I have every single bone of. Pig five, most of the bones, and pig two is still my mystery pig. I don't know why nothing likes pig two.
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