Hi, welcome back to the early to mid 2000’s where we still use jokes like “om nom nom” unironically!
Just kidding, I won’t subject you to bad jokes like that for this entire post. Anyway, it’s come to my attention that for a blog called “Animal Archaeology”, I don’t really write that much about the archaeology of animals, huh? Well, today will change that! Here is a brief introduction to how we identify gnaw marks on certain bones – because humans aren’t the only species to eat other animals, don’t ya know?
Rodent gnawing is probably the easiest one to recognise. Due to those huge incisors of theirs, rodents leave behind a very distinct pattern of close striations on the bone. Be warned, however! It can be easy to mix this up with cut marks, or vice versa.
Cats do indeed gnaw on bones! And they have a pretty peculiar way of doing so – when they hold onto a bone, they’ll use their canine teeth, which will often leave a puncture mark! Given their smaller size, these marks will often be a bit small and usually won’t go entirely through the bone (although if you’re dealing with a bigger feline, like a lion, you may find yourself with bigger and deeper puncture marks!). Cats will also do a bit of a “nibble”, leaving behind a very pitted and rough looking texture.
This is possibly something you can check right now if you have dogs as pets – take another look the next time they chew up a bone. Canine species like dogs and wolves will produce gnaw marks similar to felines in that they will often cause a puncture hole in the bone with their teeth. However, canine species will usually produce much larger holes in comparison. Another key characteristic is that canine species will slobber – when they gnaw on bones, they often produce what can only be described as “an upsetting amount of saliva” – however, this is great for zooarchaeologists, as it can leave behind a very polished look to the bone, which is very distinct. So, next time see you a beautifully polished archaeological bone…it was probably covered in ancient dog spit.
Yes, occasionally we do find human gnaw marks, although now we’re a little bit out of my jurisdiction! So, our teeth look weird – well, at least compared to non-human teeth. So the kind of gnaw marks we leave are a bit…wonkier? Is that the right word? Just bite into an apple and see what you leave behind, it’ll depend on how your incisors look, as we often lead with them to bite down onto something. Personally, I have pretty large buckteeth, so I’d hate to be the zooarchaeologist looking at my left behind teeth marks trying to figure out what the heck happened!
Parkinson, J.A., Plummer, T., and Hartstone-Rose, A. (2015) Characterizing Felid Tooth Marking and Gross Bone Damage Patterns Using GIS Image Analysis: An Experimental Feeding Study with Large Felids. Journal of Human Evolution. 80. pp. 114-134.
Yeshurun, R., Kaufman, D., and Weinstein-Evron, M. (2016) Contextual Taphonomy of Worked Bones in the Natufian Sequence of the el-Wad Terrace (Israel). Quarternary International. 403. pp. 3-15.
Note: I struggled about whether or not to write about this game due to the issues surrounding its development and the poor treatment of workers (for more information, please read this article from Jason Schreier). However, I think it marks an interesting development in the ever-growing world of virtual archaeologies, so I proceeded to write about it. That being said, please show support for the unionisation of game workers by visiting Game Workers Unite.
Red Dead Redemption 2 (Rockstar Studios 2018) has only been out for a short while, but many players have been praising the level of detail that has gone into the game. One of the most striking features, at least to me as an archaeologist, is the fact that bodies actually decay over time. That’s right, video game archaeologists – we now have some form of taphonomy in our virtual worlds!
But wait, what is “taphonomy“? Well, you may actually get a few slightly differing answers from archaeologists – we all mostly agree that taphonomy refers to the various processes that affect the physical properties of organic remains. However, it’s where the process begins and ends that has archaeologists in a bit of a debate. For the purposes of this blog post, I’m gonna to use a definition from Lyman (1994), which defines taphonomy as “the science of the laws of embedding or burial” – or, to put it another way, a series of processes that create the characteristics of an assemblage as recovered by archaeologists. This will include not only pre-mortem and post-mortem processes, but processes that occur post-excavation, as identified by Clark and Kietzke (1967).
Let’s start with the pre-mortem processes, which are often ignored in discussions of overall taphonomy – firstly, we have biotic processes, which sets up the actual conditions of who or what will be deposited in our final resulting assemblage – this can include seasonal characteristics of a particular region, which will draw certain species to inhabit the area (O’Connor 2000), as well as cultural factors, such as exploitation and, unfortunately, colonisation/imperialism (Hesse and Wapnish 1985).
Now, let’s use some poor ol’ cowboys from Red Dead Redemption 2 as examples of post-mortem processes – Content Warning: Images of (digital) human remains in various stages of decay are about to follow, so caution before you read on!
With our biotic processes providing us with these cowboys who have moved West for a variety of reasons, we now need to determine our cause of death to continue with taphonomy. This falls under thanatic processes, which causes death and primary deposition of the remains (O’Connor 2000). In our example above, we would probably be able to find osteological evidence of trauma due to the cowboy getting shot to death.
In time, we soon see the work of taphic processes, or the chemical and physical processes that affect the remains – this is also sometimes referred to as “diagenesis” (O’Connor 2000). Much of what we consider to be “decay” when we think of decomposition will fall under this category of processes. Sometimes this will also affect the remaining structure and character of bone that will eventually be recovered.
Now, imagine we take this body and, as seen in the YouTube video from which these images come from, toss it down a hill. Okay, this is a bit of an over-the-top example, but it showcases another category of processes known as perthotaxic processes. These processes causes movement and physical damage to the remains, either through cultural (butchery, etc.) or natural (weathering, gnawing, trampling, etc.) methods. Similar to these processes are anataxic processes, which cause secondary deposition and further exposure of the remains to other natural factors that will further alter them (Hesse and Wapnish 1985).
The above image shows the remains of the cowboy finally reaching his secondary place of deposition after being tossed from the top of the hill and now drawing the attention of scavenger birds – this showcases an example of an anataxic process, as the body is being scavenged due to exposure from secondary deposition.
At this point, we begin to see how all of the aforementioned processes have affected our current archaeological assemblage-in-progress: we clearly have physical and chemical signs of decay, with physical alteration due to post-mortem trauma (tossing off of a hill) and exposure (including gnawing from other animals). This results in some elements going missing, some being modified, and others being made weaker and more likely to be absent by the time the body is recovered archaeologically.
Now, we also have two processes that occur during and after archaeological excavation that, again, often get overlooked: sullegic processes, which refer to the decisions made by archaeologists for selecting samples for further analysis (O’Connor 2000) and trephic processes, which refer to the factors that affect the recovered remains during post-excavation: curation, storage, recording, etc. These are often ignored as they don’t necessarily tell us much about the context surrounding the remains, but they are vital to consider if you are working with samples that you did not recover yourself or have been archived for a long time prior to your work.
Environmental differences will also affect the sort of variety within the overall taphonomic process – for example, wet environments (say, like the body of water seen in the image above) will cause the body to become water-logged, which may speed up certain taphic processes and create poorer preservation. More arid environments, like a desert, may lead to slightly more preservation in some cases due to the lack of water that may damage the bones.
Although the game certainly speeds up these processes and streamlines them in a way that removes some of the other variables that you would see in real life, I’d argue that Red Dead Redemption 2 might currently be the most accurate depiction of taphonomy that exists within a virtual world and may present new opportunities for developing models that could aid in furthering our understanding of how remains may decay under certain circumstances.
At the very least, it could make it easier and less smellier to do taphonomic experiments!