What Makes Us Resilient?

In my last post, I highlighted archaeological research that showed that strong communities – local-level groups that worked together and maintained social ties – helped past societies weather major disruptions, delivering better outcomes for human health and prosperity and even helping sustain institutions above the local level. These are promising results for us, pointing to at least one practical way we can combat the effects of the pandemic. Working to support and maintain our communities now will help us come out of this pandemic in the strongest way we can. But the researchers’ conclusions also raise an obvious question – what are local communities doing or providing that contributes to their larger societies being resilient to a crisis?

There are dozens of books on resiliency from the past decade alone, but most focus on recent societies and institutions. Resiliency is a popular topic in archaeology as well, but many studies of resilience in the past focus on just one culture or time period. Here I will highlight an excellent cross-cultural study by Peter N. Peregrine, an anthropologist and archaeologist at Lawrence University. Peregrine examined 33 archaeologically known societies that weathered 22 environmental crises to test two hypotheses: did either local participation in decision-making or rigid social norms help human societies weather environmental crises? These two strategies have both been identified as sources of resilience in contemporary societies, but archaeology can test their utility in a broader range of cases. Again, the strength of Peregrine’s study is that it analyzes completely unrelated societies across large spans of time and space. As Peregrine puts it: “If a predictor of social resilience to climate-related disasters can be identified and applies to societies of varying scales and complexities throughout human history, then there is good reason to believe that it can be used to create interventions applicable today.”

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Inside the water temple of S. Anastasia in Sardara, Sardinia – a site of communal ritual for the Bronze Age Nuragic Culture

Peregrine trained research assistants to code ancient societies that faced severe environmental crises according to where they fell on scales of “corporate-exclusionary” (level of participation in decision making) and “looseness-tightness” (enforcement of social norms). They also coded how resilient the societies were by evaluating seven variables – population, health and nutrition, conflict, household organization, village organization, regional organization, and communal ritual – both before and after the environmental crises occurred. You’ll notice how many of these variables are similar to those used by the LTVTP-NABO collaboration I highlighted in the previous post, reflecting the basic kinds of human well-being we hope to be able to maintain even in crisis situations.

Peregrine found a positive relationship between resilience to environmental crisis and high levels of participation in decision making*. When leadership was more fluid and open to input and action at local levels, societies were more resilient, maintaining higher levels of well-being throughout the crisis. Peregrine found the opposite for enforcement of social norms, however; societies with strict enforcement of social norms were less resilient to environmental crisis. For the diversity of cultures and over the long time scales studied by Peregrine, rigid codes of behavior were detrimental.

A pandemic doesn’t pose the same challenges as an environmental crisis, but the importance of Peregrine’s findings is still apparent. One factor in creating resilience is broad participation in local decision making and a willingness on the part of higher levels of government to listen to local voices. It makes sense that local people are the often the first to recognize how a crisis is affecting their particular community and that they are likely to have useful ideas for how the crisis needs to be handled to maintain well-being in their area. The current pandemic poses unprecedented hurdles for average citizens trying to participate in governance, but it is essential that we find ways. Making local decisions based on local input is key to maintaining our well-being.

 

* I prefer to feature open access research so everyone can read and evaluate the work for themselves, but if you happen to have access to academic journals, I recommend the following archaeological and historical study. It reaches conclusions similar to Peregrine’s regarding the role of local-level knowledge and participation in decision making for achieving sustainable soil use in case studies of ancient Mediterranean agriculture.

Butzer, K (2005) Environmental history in the Mediterranean world: cross-disciplinary investigation of cause-and-effect for degradation and soil erosion. Journal of Archaeological Science 32: 1773-1800.

Archaeology vs. COVID-19

Last week, I argued that archaeology has something useful to say in this time of Coronavirus. This may seem like a bold assertion, even to other academics. I wonder how many of my colleagues in economics, sociology, and psychology see archaeology as a social science like their own disciplines. I wonder how many people in general look at today’s problems – be they Coronavirus or climate change – and think “let’s ask the archaeologists.”

I’ll be the first to admit that my argument needs to be supported by evidence before anyone should take it seriously. So that’s what I intend to do: provide evidence that the broad human past gives us valuable insight into what we can and should do now. I’ll focus on open access studies that anyone can read, and I encourage everyone to read the originals and assess for yourselves whether these are good evidence for the contemporary relevance of archaeological insight.

My first piece of evidence is an article* by Michelle Hegmon and Matthew Peeples on behalf of the LTVTP-NABO collaboration. The Long- Term Vulnerability and Transformation Project (LTVTP) focuses on archaeological cases of social transformation in the arid and semi-arid United States Southwest and northern Mexico. The North Atlantic Biocultural Organization (NABO) focuses on cases that took place in the subarctic and arctic North Atlantic. Together, the LTVTP-NABO collaboration examined 18 examples of major social transformations as varied as the end of the Norse occupation of Greenland and the depopulation of the Mesa Verde region. The geographical, environmental, chronological, and cultural diversity of the cases studied suggests that any strong patterns probably hold true for human societies generally: that is, they point to specific ways that all human societies tend to respond to stress.

The researchers coded a broad set of variables, from institutional breakdown and depopulation to human securities**, migration, household organization, and changes in material culture (the archaeological catch-all term for “stuff”). The researchers then performed correspondence analyses among these different variables to identify meaningful relationships.

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Figure 3 from the cited article showing correspondence analysis of all human securities variables. Red and yellow cases have higher levels of breakdown.

Their results are fascinating and the paper is worth a detailed read, but some of their conclusions feel particularly relevant in the current crisis. First, there is a strong relationship between the breakdown of institutions and a decline in human securities. No one is an island: nobody thrives when we let our sustaining institutions crumble. How we get food, how we receive medical care, and how we keep interpersonal violence in check are all embedded in institutional systems. If those systems fail, we’re likely to suffer. We’re witnessing severe stresses on some of our systems right now as they struggle to keep up with the demands created by the current pandemic.

 

The hopeful part of the study is that the researchers identified communities and community security as strong predictors that social transformation would be less painful. If communities remained strong – if they didn’t disintegrate under the weight of social transformations – people experienced less food insecurity, less interpersonal violence, and less death. The researchers also found a positive feedback loop – strong communities could bolster institutional security, preventing or dampening the major institutional collapses that were found to be disastrous in the less fortunate cases. The authors conclude: “We must consider the people’s experiences because what happens at the local level can stabilize society, can augment people’s capabilities for contributing in positive ways, and thus can help avert disaster.”

I’m probably not the only one who’s found herself reaching out to friends she hasn’t talked to in years to check on how they’re doing in this crazy situation. It turns out this normal human impulse may have a practical benefit. Cross-cultural, cross-temporal evidence reminds us that our communities make us resilient. Strong communities protect and provide and care for us when larger institutions falter and can even prop up those institutions until they recover their footing. Community-building in the time of Coronavirus may not look like it used to, but it’s one of the smartest things we can do.

 

* Hegmon M, Peeples MA, on behalf of the LTVTP-NABO collaboration (2018) The human experience of social transformation: Insights from comparative archaeology. PLoS ONE 13(11): e0208060. https://doi.org/10.1371/journal.pone.0208060

** The researchers followed the United Nations definition of seven types of human securities to assess human security broadly: economic, food, health, environmental, personal, community, political.

Archaeology in the Time of Coronavirus

This is my first post about my new research project ZANBA: zooarchaeology of the Nuragic Bronze Age. This isn’t the post I expected or wanted to write. But none of us are doing what we expected or wanted right now. Fighting the pandemic is rightly taking precedence over our plans. So these days I’m sitting on my couch or looking out my window at empty parking lots and wondering – how do I “do” archaeology in the Time of Coronavirus?

I expected to be in the field right now, getting ZANBA off the ground: meeting with the Soprintendenza, discussing permits, reestablishing lab access, taking a look at the bags of animal bones I haven’t touched since fall 2018. I was hoping to revisit some of the monuments where I work so I could finish an article that’s 90% written. I was going to see my friends. The trip was going to be low pressure and exciting. It was going to be fun.

Obviously, that trip has been cancelled. I’m still seeing my friends, but it’s for virtual cocktails over Zoom. Our conversations only occasionally touch on work. They focus on concern for each other’s safety and heavy doses of encouragement.

***

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Lab training for ZANBA, on hold for the moment.

I arrived in Wales to begin my new project in early January, just days before the novel coronavirus was identified. In January, the feeling around me was of an emergency happening somewhere else. In February, the feeling was of a concern that would only seriously affect a few. In March, the feeling went from “this is probably overreacting, but…” to “this is a national health emergency” in a matter of days. On Friday, March 13, my university announced that in-person teaching would end after one more week. The following Monday morning, it announced that in-person teaching would end after Wednesday. By that Monday evening, in-person classes were cancelled and staff were encouraged not to return to the building on Tuesday. The world was changing fast.

***

The world is changing fast, and it can be hard to grasp what a slow-moving discipline like archaeology has to contribute in a crisis. The logistics of excavation and survey mean it can take years to gather our primary data. The constraints of collaborative research, shared labs, and intermittent funding mean it can be years again before we publish our findings. Most of our work investigates people who died a long time ago. Realistically, should the public care at all right now what the archaeologists have to say?

YES. Archaeologists can answer some of the most important questions people are worried about right now. Not about how to protect ourselves and our loved ones from the virus (stay home, wash your hands!) but about what things might look like after. How do societies respond to crises? How do crises differentially affect cities, towns, and rural settlements? What happens after a crisis? How do societies recover – or not? How long does recovery take?

Archaeologists have experience interpreting a global dataset that stretches back 250,000 years. We’ve studied how a lot of human systems have contracted and collapsed, as well as how they’ve adapted and been reinvented. It may feel like archaeological information can’t be comparable to what we’re going through today – ancient people didn’t have jets and stock exchanges and the internet. But most archaeologists will tell you that the roots of resilience in the past are the same as those in the present: maintaining the flow of accurate information, good decision-making, robust supply chains, and a willingness to do things differently when necessary.

Many archaeologists are trained in an anthropological framework that encourages us to see ancient people as culturally different, but cognitively and biologically the same as we are today. This perspective means that archaeologists can’t fall back on the comforting but false idea that real crises won’t happen to us because we’re too smart, scientifically advanced, or technologically capable. Archaeologists know that ancient people were just as smart as we are, and we’ve seen plenty of evidence that – no matter how smart we are – our human trajectory never goes endlessly up.

But we’ve also seen that dips in human trajectories vary widely in their aftermaths. Sometimes large-scale projects and long-distance communication all but disappear for centuries, but it doesn’t always happen that way. Sometimes people respond quickly and there’s a new period of growth. Sometimes the dissolution of sweeping hierarchies leads to more successful local systems. All kinds of outcomes are possible. Both individual and institutional responses matter, and adaptation is key.

The archaeologist who is my coauthor on the article that’s 90% finished is a specialist in photogrammetry. He’s currently adapting his skills to 3D print face shields for medical workers. We all have skills that can be adapted to the current moment. They may be as simple as the ability to keep ourselves entertained while staying inside, but these skills are saving lives.

We also have skills that will help us adapt to whatever future emerges from the current crisis. None of us knows right now how long this will last or what the long-term effects will be on our social networks, our economies, and our way of life. We’re taking this one day at a time. But as we move forward, consider talking to the archaeologists. Our case studies are different but relevant, and we’re trained to take the long view.

And please, please protect yourself and others by staying home and washing your hands!

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Documenting remains of the Nuragic Culture on the Siddi Plateau in 2019. Hopefully I’ll be able to return soon to finish that work!

Was Sardinia Atlantis? Hint: No.

If you’ve ever Googled Sardinian archaeology, you’ve probably run across the idea that Sardinia was Atlantis. The idea is common on the island itself due to a popular work of pseudoarchaeology. The claim that Sardinia was Atlantis has now been picked up by English-language sources, including a recent National Geographic special.

Now there’s pretty much nowhere on earth that someone hasn’t claimed is Atlantis, so in that sense, Sardinia isn’t special. But in case there was any doubt in your mind, in case you thought maybe Sardinia was the one place on earth that really was Atlantis, let me just tell you:

No.

Sardinia was not Atlantis. Nowhere was Atlantis. Atlantis was always an allegory; it was never a real place.

Nevertheless, the idea that Sardinia was Atlantis is persistent, and it’s being actively promoted. There are many problematic layers to this misinformation, one of the most insidious being that it’s being promoted using a lot of gorgeous images of Sardinia’s real archaeology, which is genuinely mind-blowing.

How could you not be impressed by the cultural patrimony of an island that includes literally thousands of towers like Is Paras?

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Is Paras, one of Sardinia’s many spectacular archaeological sites (photo E. Holt)

This juxtaposition of archaeological imagery with fantastic claims blurs the lines between reality and fiction and draws people into accepting the misinformation because it appears to be supported by evidence. Unfortunately, like most pseudoarchaeology, the links between the fantastic claim and the real archaeology are cherry-picked and superficial, and the evidence that proves the fantastic claim is wrong is never presented at all.

The claim that Sardinia is Atlantis has been well and thoroughly debunked by many Sardinian archaeologists, historians, and geologists and you can read their Italian-language response here. But if English is your thing, you can also listen to me discuss these issues on the podcast Archaeological Fantasies.

Many thanks to Sara Head, Jeb Card, and Ken Feder – the hosts of Archaeological Fantasies – for having me on the show! You can check out Ken’s work on frauds and myths in archaeology here and here, and Jeb’s work on pseudoarchaeology here.

Ancient Astronomy

It’s been a busy few months! I just wrapped up teaching an intense semester, and I have one day to pack and prep my apartment before I leave for the holidays and – immediately afterward – a month-long research trip to Paris. I plan to be blogging again soon, but in the meantime, I had the pleasure of being a guest on Paul Sutter‘s podcast Space Radio. Paul Sutter is an astrophysicist at The Ohio State University and a brilliant science communicator (definitely check out his new book if you’re interested in astronomy). He asked me to join him on Space Radio to explore how ancient cultures understood astronomy.

You can listen to our discussion here.

Theory in Archaeology

The students in my Ancient Cities course recently encountered an insightful but challenging reading, a chapter in a book dense with that most hated of academic discourses: theory. Just say “theory” at someone – and I don’t mean only undergrads – and their eyes will glaze over and they’ll visibly fight the urge to check their Twitter notifications.

Unless they’re like me. I love theory. Theory is my favorite thing in all of archaeology to teach. Understanding theory means deciphering the tangled logic puzzle of “how do we know what we know.” Understanding theory means making clear – and then criticizing – all the unstated thought processes that archaeologists go through in making sense of our information.

For example, take a string of numbers: 17351. You can observe the numbers written here, but if someone made you stop reading this post right now and asked you what those numbers meant, you’d probably say “who knows.”

But what if you kept reading and saw that I added some symbols in with the numbers: 17 x 3 = 51. Suddenly you can say something about the numbers. They’re a multiplication problem. There’s a relationship that makes the first three numbers equal to the second two numbers. The first two numbers should be considered as a unit, the third number is a unit on its own, and the last two numbers are also a unit.

We’ve applied theory to the numbers. Now we can say what they mean.

Archaeological theory works with artifacts like mathematical operations in a string of numbers. Theory structures the relationships among artifacts and other archaeological data, allowing archaeologists to understand how they interact. Without theory – and the application of theory, which we call method – archaeologists would endlessly collect old things without actually adding to our knowledge of the past. We would dig up artifacts, document architecture, maybe even identify some campfires and postholes, but we wouldn’t know what any of it meant. It would just be a string of numbers… er… artifacts.

The early days of European curiosity about the past were full of “strings” of artifacts – in reality, these were drawers, boxes, cabinets, and rooms that housed jumbled assemblages of ancient objects. Antiquaries1 of the late Renaissance and the Age of Enlightenment collected these objects – sometimes digging into barrows or other monuments to find them – and documented the existence of ancient sites. But they found themselves trying and failing to describe relationships among the sites and artifacts. They hadn’t developed any archaeological theory, so they couldn’t interpret what their finds meant. The problem was so acute that the Danish antiquary Rasmus Nyerup (1759-1829)2 complained that “Everything which has come down to us from heathendom is wrapped in a thick fog.”3

Fortunately, antiquaries began developing foundational theory that allowed them to start organizing finds. Ideas like the Three Age System – which was proposed in 1816 and divided European prehistory4 into Stone, Bronze, and Iron Ages based on the primary materials used for tools – allowed antiquaries to begin recognizing relationships among their materials. Other types of theory like the concepts of typology and seriation – the idea that artifacts that looked similar probably came from similar time periods and that these time periods could be arranged chronologically – moved the study of the past from antiquarian collecting into the budding discipline of archaeological explanation.

Great, you say. Antiquaries formulated theory, applied it to artifacts, established archaeology, and now we know what the past means. But not so fast – let’s return to that string of numbers. What if instead of making it a multiplication problem, I use different symbols: |1 x 7 – 3 – 5| = 1. This way of interpreting the numbers is equally consistent and so equally valid as the first.

Archaeology works like this, too. Often, multiple ways of applying theory give us internally consistent understandings of the past. What if I asked you for an ecological explanation of why I wore my orange sweater today? You might say I wore it because the weather turned cold and I wanted to stay warm. But what if I asked you for a postcolonial interpretation of why I wore my sweater? Then you might say it relates to my position within a historic system that channels global resources toward the west, making it possible for me to own a (probably excessive) number of warm sweaters. Both these ways of applying theory to my sweater produce perspectives that are true and useful for understanding my experience.

Now don’t get me wrong: the past is not all relative. Archaeologists can demonstrate that many ways of understanding the past are straight-up false, and it is not the case that every interpretation is as good as any another. For example, what if I ordered my numbers like this: 1 + 7 + 3 + 5 = 1. That’s simply wrong. Unlike my first two proposals, this interpretation of the numbers does not show a logical relationship. Or what if you claimed that I wore my orange sweater because I always wear orange on Wednesdays. Examining my other Wednesday wardrobe choices would show you this is not an accurate explanation.

Even though not all understandings of the past are true, it is true that the past was as rich and varied as human life today, so it shouldn’t surprise us that multiple ways of understanding the past can be accurate and provide insight. And thanks to a long history of archaeological thinking, we’re not at a loss to distinguish the good explanations from the bad. Robust archaeological theory provides the tools we need to tell the difference between rigorous interpretations of the past and ones that don’t stand up to scrutiny.

 

  1. The term “antiquary” refers generally to a person who studies the past and is especially used to describe people who collected ancient artifacts and documented sites in the period before archaeology became a field.
  2. (2009). Nyerup, Rasmus. In The Concise Oxford Dictionary of Archaeology, 2nd edition (online). eISBN: 9780191727139 DOI: 10.1093/acref/9780199534043.001.0001
  3. Page 51 in Fagan, B. M., and Durani, N. (2016). A Brief History of Archaeology. Classical Times to the Twenty-First Century, 2nd edition. London and New York: Routledge. ISBN: 9781138657076
  4. The Three Age System was specifically applied to Danish prehistory when it was first proposed, but it was found to be broadly useful and adopted for European prehistory in general.

The Semester Starts in Earnest

If you’ve read my post about Archaeology in the Off-season, you know I’ve been busy since I returned from Paris last November. Archaeologists always are. The time when we’re not in the field is when we read the latest scholarship, learn new skills, and write our own books and articles. It’s some of the busiest time we have.

These last two months have been no exception. I’ve been intensely busy settling into my new job as a Visiting Assistant Professor in the Department of Classics at Miami University of Ohio.  I’ve also been preparing an application for a Marie Curie fellowship at Cardiff University, and writing a major fellowship application is almost as much work as an article. But I submitted the Marie Curie in mid-September – fingers crossed! – and I’ve found my footing teaching Greek Civilization, Ancient Cities, and Discoveries of Archaeology. I even got word that another of my book reviews is out in the Journal of Near Eastern Studies. It feels like a lot of old projects are wrapping up, and you know what that means:

New projects.

It’s time to dive back into a couple of things I’ve kept on the back burner for too long, as well as decide on new directions for the coming academic year. It’s an exciting prospect, almost heady: I’ve been working on a backlog for so long, I barely remember what it’s like to have a front-log.

I have two main goals for the coming academic year: submit some articles and step up my public outreach. I’ve already started on both. I’ve actually been surprised how easy it is to get back into scholarly writing. It turns out all the thoughts that were kicking around in my head while I was updating my encyclopedia article and finalizing my edited volume just can’t wait to get onto the page.

I’m also really excited to try out new methods for communicating archaeology to the public. I bought some materials from Forestry Suppliers – that mainstay of archaeological equipment – and I’m looking forward to putting them to use. Stay tuned to see where my new photographic scales turn up!

I’ll write more about specific projects as the semester progresses, but for now, a draft of an article is calling.

Onward.

Archaeology in the Off-season

I apologize, readers. It’s been a long time since I posted anything in Errant. Too long. I have no excuse except I’ve been busy.

“Haven’t we all,” you reply.

Touché, touché…

Even if I have no excuse, it’s true that archaeologists do a lot of work in the off-season. The stretches of time between our intensive fieldwork and lab work sessions is when we read articles, write articles, become familiar with the latest techniques, and build new skills. So what did I do that took so much time I couldn’t write?

Well, I learned French. Not enough to spontaneously compose the complete works of Zola (or even read them), but enough to earn a C1 rating on the Test de connaissance du français. Through a combination of the free online resource Duolingo, listening to the Journal en français facile, watching France 24 on YouTube, reading several novels, and watching hours of sitcoms (subtitles off), I immersed myself in French language and grammar for two intense months. Then I traveled to Chicago – the nearest city where the TCF is given – and took my chances. The hard work paid off.

My desire to learn French is mostly personal: the research team I work with at the Museum national d’Histoire naturelle speaks excellent English. Even so, I feel it’s both respectful and useful to speak the language of the country where you’re working, wherever that happens to be. Everything from buying groceries to working with local governments goes more smoothly when you can communicate in people’s preferred language, and the show of good faith goes a long way, especially if you work in an area where there’s a reputation for colonialism left over from archaeology’s Bad Old Days.

But French wasn’t my only project since November. I also finished editing a book. Water and Power in Past Societies is the result of an international conference of invited scholars that I organized when I was the postdoctoral fellow at the Institute for European and Mediterranean Archaeology. Editing the volume that resulted from that conference has been a major part of my scholarly life ever since, and this year it finally drew to a close. Immediately after my trip to Chicago, I turned my attention to the line edits and indexing, and the book appeared in print in April. I couldn’t be prouder of the result, or more grateful for the opportunity to work with the inspiring scholars whose research is featured.

Still, editing a book didn’t seem like quite enough, so I wrote reviews of three others. Professional book reviews are an essential part of most peer-reviewed journals, and they help colleagues decide whether particular books will be useful for their research or teaching. Writing reviews is also a good way to get a free copy of a book you want to read, but don’t be fooled – when I divided out the price of the books I reviewed by the number of hours I spent working on each review, my average pay came to about $4 an hour. Two of the reviews are still forthcoming, but you can check out one of them here if you’re curious.

Not everything I worked on since November was a new project. One was an old project that landed back on my desk rather unexpectedly. In 2014, I wrote an article on Nuragic archaeology for the Encyclopedia of Global Archaeology, and right around the time I left Paris, I was informed it was time for me to update it. A number of new works had come out in my field since 2014, so updating the article meant catching up on a lot of scholarship I had been neglecting while my attention was focused on Water and Power.

And last but not least, when all the rest was done, I managed to write a 20-page report on the zooarchaeological research I did at Tel Akko in Israel last summer. Working in a new area of the Mediterranean was extremely challenging, but the results were worth the effort. My contribution is only a small part of this ongoing research project, of course – I can’t wait to see what new excavation seasons add to our knowledge of animal economies and environments at this fascinating site.

So that’s pretty much what I did. Of course, all these projects were in addition to my work-for-money jobs, which included teaching archaeology and anthropology at Miami University and working as an Experience Programs Teacher at COSI, Columbus’s wonderfully engaging hands-on science museum. I’m pleased to say that, as the summer draws to a close, I’m looking forward to continuing as a Visiting Assistant Professor in the Miami University Classics Department and volunteering a few times a month at COSI.

I’m also looking at clean slate with no outstanding projects or professional obligations. I wonder what I’ll work on next…

Micromammals Tell a Mega-Story

Most research in archaeology happens in a lab. Despite the images of sweaty excavators and big hats that come to mind when “archaeology” is mentioned, the bulk of archaeology happens when the digging is done. It’s a truism among project directors that you plan three days in the lab for every one day in the field, but the essential work that goes on behind the scenes is largely invisible to the public.

I’m a zooarchaeologist – an archaeologist who studies animal remains – and I do most of my work in labs. Right now, I’m working at the Muséum national d’Histoire naturelle in Paris, where I study the bones of micromammals like mice and voles. These tiny remains were excavated from Bronze and Iron Age sites on the island of Sardinia (c. 1700-300 BCE), and despite their small size, they help me answer big questions about the cultures I study. Micromammals are sensitive to the environments around them. Different species have particular preferences for habitats and living conditions, which means that identifying the micromammals at a site is a way to reconstruct the site’s environment. And reconstructing the ancient environment is fundamental to understanding everything from past economies to climate change.

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I use a microscope to examine bones for evidence of digestion by predators

A typical day of zooarchaeology includes multiple projects. Today, I’m working on three. I begin the day by tackling a taphonomic analysis of the micromammal remains. Taphonomy is the study of how ancient bones are incorporated into archaeological sites, and it includes everything that happens to the bones after the animals die. You can imagine why taphonomy would be important for interpreting ancient bones. Let’s say, for example, that the ancient environment was swampy, so the local micromammals were adapted to wet terrain. But if there were grasslands nearby, an ancient owl could nest in the swamp but hunt in the grasslands, scattering bones of grassland species around its nest. A case like this will give you a confusing mixture of grassland and wetland species showing up together – so what was the ancient environment really like? A careful taphonomic analysis can sort out which species died at the site and which were brought there by predators, helping differentiate the immediate local conditions from the wider surroundings.

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Special software lets me capture detailed images of the micromammal teeth

After a morning in front of the microscope recording taphonomic clues, I’m ready to move to my second project. This project uses geometric morphometrics – a kind of spatial statistics – to analyze the shape of micromammal teeth. The shape of the teeth shows genetic plasticity, meaning that it changes depending on which groups of micromammals bred with each other. Looking at the shape of ancient teeth is therefore a way of tracing population dynamics, and when the only way new micromammals get to an island is by sneaking onto ships, ancient micromammal interactions become a proxy for ancient human interactions.

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Drawers full of tiny reference skeletons at the Muséum national d’Histoire naturelle

I spend several hours taking images of the micromammal teeth. When I’ve captured images of all of the teeth, I’ll use specially developed software to compare the teeth with each other and with teeth from archaeological sites around the Mediterranean. Capturing the images takes up the major part of my day, but it’s only the beginning. Outlining each tooth so I can compare their shapes will take days. It’s a slow process, and I’ll work on it a little at a time after I return to the states.

 

 

I have just about an hour left in my day, so I decide to spend it studying. My third, long-term project is to do an environmental reconstruction for my site in Sardinia – Sa Conca Sa Cresia – which I excavated with my colleague Mauro Perra in 2009-2011. Even though we completed the excavations a while ago, I’ve only recently finished sorting the heavy fraction to remove the tiny micromammal bones. To prepare to do a complete environmental study, I first consult The Atlas of European Mammals to see which species are currently known to exist on the island. Then I visit the Muséum’s reference collections to familiarize myself with the characteristics of these species’ bones – and especially their highly diagnostic teeth.

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The number and shape of the cusps make teeth “diagnostic,” meaning they can usually be assigned to a species

By the end of the day, my brain is fried. I cover the microscopes, turn off the lights, and make my way to the metro line 7, then transfer to the 6. I’m in a bit of a daze, but it’s a good kind of exhaustion – similar to how muscles feel after a trip to the gym. It’s an exhaustion that lets me know I deserve to take the night off. And there’s no better place for a night off than Paris. 

 

Magnifiers, Mouse Teeth, and Hope

Archaeologists love their equipment. Most of us can tell you when and where we got our first trowel, when and where we got our last trowel, whether we prefer a leaf blade or a pointing blade or a margin blade, why we buy Marshalltown or WHS or Battiferro. And it isn’t just our trowels. We’re obsessed with our hand picks, our Leatherman tools, our GPS units, our water bottles, our boots, and – perhaps the one realistic thing in the Indiana Jones movies – our hats.

It doesn’t stop with field archaeology. Lab archaeologists are just as intense about their microscopes and stereo macroscopes, their sonic cleaners and deionized water, their bags and bottles and pipettes. I’m as bad as the next archaeologist when it comes to equipment, so when a magnifying lamp I ordered finally arrived on Wednesday, I was stoked.

My lab in Sardinia is still being set up. I buy a few new pieces of equipment each time I return, and this year’s addition of a magnifying lamp is a significant upgrade. It enables me to take some time for a second zooarchaeological project that has been on the back burner for a year now. That project is looking for mouse teeth.

Yes, mouse teeth. Mouse teeth may sound insignificant, but these adorable, tiny fragments of ancient Rodentia are actually quite meaningful. Rodents are sensitive indicators of their local environments, and some species have particular relationships with humans that archaeologists use to understand how ancient people lived. In an ongoing research project that I’m pursuing in collaboration with the workgroup Mousetrack, run by Dr. Thomas Cucchi at the Muséum national d’Histoire naturelle, I’m using different mouse species to understand when exchange relationships developed between Sardinia and the cultures of the East Mediterranean. This is an important question because archaeologists debate whether the prehistoric cultures of Sardinia were more isolated or more connected to other Mediterranean groups.

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Sorting for mouse teeth with my new magnifying lamp

I took my new lamp to the lab first thing on Thursday morning and set it up at a specially reserved desk. This desk is now my mouse study desk, where I do the painstaking work of sifting through what archaeologists call “heavy fraction.”

When archaeologists dig, they collect a sample of sediment from every important stratigraphic layer. This sample of sediment is then mixed with water and agitated in a process called “flotation.” Flotation can be done by hand in a bucket or with a variety of more or less sophisticated pump-and-barrel mechanisms, but the point is to get carbonized plant remains to rise to the surface. The floating material – which sometimes also includes fish scales and tiny bones – is called the “light fraction.” We collect it using an extremely fine mesh like chiffon and dry it carefully, preferably out of direct sunlight (if carbonized seeds dry too quickly, the difference between the dry surface and the wet interior can make them break).

The stuff that doesn’t float during the flotation process is also collected, usually in a slightly larger mesh with holes about 1 mm2. This is the heavy fraction, and it’s where we find lots of tiny animal bones as well as pottery, chipped stone, metal, glass – any heavy material that breaks into small pieces. The tiny artifacts that show up in heavy fraction can be fascinating. Beads and jewelry, nails, pins, and fragments of carved bone are all common. Food waste is also common, and evidence for small foods like eggs, fish, and sea urchins is often recovered only in the heavy fraction.

The heavy fraction I’m sorting comes from my excavation of the early Nuragic site Sa Conca Sa Cresia, located on the small plateau near Siddi, Sardinia, that also includes Sa Fogaia. I co-directed the excavation of Sa Conca Sa Cresia with Sardinian archaeologist Dr. Mauro Perra between 2009-2011. The excavation was very successful and our analysis of the resulting artifacts is ongoing – a good rule of thumb is that archaeologists expect to spend three days in the lab for every one day of excavation.

At first, sorting heavy fraction feels like doing excavation in miniature. It’s exciting to notice the shiny flakes of obsidian, the broken pottery, the piglet toes and lizard jaws and frog legs as they emerge from the tiny rocks that make up 99% of the heavy fraction. After a while, though, I start to get nervous. Where are the mouse teeth? Why haven’t I found one? Will I end up finding any at all, or will I just spend hours of precious research time looking for something that isn’t there? The problem, of course, is that there’s only one way to answer these questions, and that is to get in there and sort.

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Got one!

Realistically, I was rewarded pretty quickly with my first mouse tooth. And not just any tooth, a first molar of the mandible: the specific tooth that is most useful for my study. My heart leapt a little as I recognized the characteristic shape, and I picked it up gingerly and transferred it to a plastic specimen tray. I couldn’t say immediately what species the tooth belonged to – that requires careful cleaning and more powerful magnification – but the tooth was the right size to be one of the species I’m interested in.

It was an exciting find, and it re-energized me for a while. But after a couple of hours, the frustration crept back in. Then the concern. Obsessively, I sorted on.

When you’re invested in the outcome, sorting heavy fraction feels like playing a weird archaeological slot machine. I use flexible tweezers to spread out a small pile of sediment, then examine it minutely with the magnifying lamp. “C’mon, mouse tooth!” I say to myself as I flick past the ribs and toes and vertebrae that aren’t relevant for my study. There’s lots of what I don’t want, but is there anything I do want? No, nothing. I push this pile of sediment to the other side of my tray and start a new pile: “C’mon, mouse tooth…”

The hope is addictive. The possibility that each little pile of sediment might hold the tooth I’m looking for. The possibility that the tooth might belong to a significant species. The possibility that enough significant teeth will add up to a significant find, a meaningful advance in what we as humans know about our past. Students sorting heavy fraction for the first time usually put down their tweezers after fifteen minutes. “You do this all day?” they ask in disbelief. “Don’t you get bored???”

Yes, I get bored. But I stay hopeful.

After non-stop sorting for three days, I’m almost finished. I currently have eight new teeth, an average of less than one tooth for every liter of sediment. I’m hoping to find one more, but the sediment I’m working on now includes very little cultural material of any kind. There are only the rarest fragments of pottery, obsidian, or bone. Still, you never know. I always have hope.

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Four mouse teeth – a full day’s work