From Macro to Micro: Characterizing Lithic Raw Materials

This is where I take archaeology and geology, smashing them together in a glorious mess.

In order to source the lithic (stone) raw materials that we recovered in our assemblages (see previous entry "My Research 101" for explanation as to why I am doing this), I am attempting to describe the stone types in a way that is based in geology but is accessible to archaeologists with little or no background in geology. I do have a limited background in geology myself, mostly a few introductory courses along with some upper level ones in sedimentation and stratigraphy, GIS mapping, and mineralogy, but I am not a geologist.

I am describing our lithic artifacts using both macroscopic and microscopic attributes. Macroscopic attributes are those visual characteristics (colour, patination, lustre, mottling, speckling, banding, texture, inclusions, etc.) that you can see via the naked eye. Microscopic characteristics are those that require the use of, obviously, a microscope (preferably a polarizing microscope). These include mineral content and relative proportions, fabric, and texture among many others. The lists of attributes I am recording are derived from those used by geologists to describe and characterize rocks within the three major rock types: igneous, metamorphic, and sedimentary.

Macroscopic analysis is frequently not adequate for distinguishing between different rock types thus necessitating the use of microscopic analysis. Further, microscopic analysis often can tell us a lot about the specific formation environment of that particular rock (i.e. it's source). Chert is a great example to further clarify this.

Chert, overall, is highly variable. Within a single formation of chert there can be a considerable amount of variation in it's visual (macroscopic) characteristics. Even if the source is visually homogeneous there may be microscopic variations between the various members of that formation. Thus, when we talk about variation in cherts we can talk about inter-source variation (that between different sources) and intra-source variation (that within a single source). However, inter-source variation can be quite low too. You can have several sources of chert that all look visually the same, so we need to look at the microscopic features of each source individually to distinguish which one is which. We also have to look at a number of samples from each source must be look at in order to account for intra-source variability. Now if we don't have descriptions of the sources, like in this case (we did a field season of survey and were not able to find any potential sources, and this is the first study of its kind to occur in this region so there is no baseline data), we can still look at the microscopic attributes of the cherts to at least determine how many (potential) sources were being used and what formation environments should we expect to find these sources.

So I start by grouping the cherts into "types" based on their macroscopic features. I then sample each "type" for thin sectioning. These thin sections are then analysed for their microscopic attributes and again grouped into "types" based on similarity or difference to each other. Hopefully the macroscopic types will correlate with their microscopic types. If not, that's ok too - what that means is that it is likely there is intra-source variation. Either way I need to then look further at the microscopic attributes of the types to try to connect them to a formation environment. Again, certain microscopic features can allow me to say that this chert was formed in this particular environment over another. The idea is to then go back to the geological maps for the region and identify possible formations that match the microscopic evidence for where the chert could have come from so we can go back into the field and check them out.

Whether I am able to find the sources or not, it is my hope that the method I am using, and the charactertization scheme I am developing, will allow archaeologists working in Tanzania to describe their assemblages in a standardized way. This will then allow us to start to look at similarities and differences in raw material selection and use within and between various regions of the country.

In the future I'll post some pictures to clarify what I've tried to explain above. Eventually, once my research is done, I am going to develop a website where anybody can see descriptions, photos, and microphotographs of all of our raw material types (not just the chert).

Book club for October: Water for Elephants by Sara Gruen

Last week our book club, "The Bookies", met to discuss our first book of the year "Water for Elephants" by Sara Gruen. It was a great choice to start off with as it was well received by all.

"Water for Elephants" is simply about a man, Jacob, reflecting back on his time with a train circus,"The Benzini Brothers Most Spectacular Show on Earth", during his 20's. As his recollections of his past become crisp and detailed, Jacob is dismayed to find that his mental acuity in the present day is fading. Indeed he is unsure even as to his own age, though he is quite sure it is either 90 or 93. Often and much to his dismay, he seems to "awaken" from a recollection to find that he was speaking about it out loud. He can no longer keep track of "his people" - the relatives that visit him every sunday though he may recognize certain features in a grandchild or great grandchild (a smile, eyes, a laugh) as belonging to one in particular of his five children.

His own struggle with the affects of aging, in addition to the underlying social commentary on nursing homes, hit home with many of the Bookies. We had a great discussion concerning our own thoughts and fears regarding aging. Particularly, the emotional conflict between wanting to care for own parents in their old age but not wanting to be a burden our (future) children when we are the elderly ones requiring assistance was debated, as was the idea that our society/culture is perhaps too selfish and disposable (i.e. that we do not venerate our elders but "throw our old people away" by placing them in care facilities rather than bringing them into our own homes). A stimulating, but almost melancholic, discussion!

We agreed that one of the major strengths of this novel is that not only are the human characters memorable and interesting, but Gruen does a great job of bringing the individual personalities of the animals in the circus menagerie to life. From Rosie the elephant (who we all wanted more of) to Queenie the terrier, Gruen's animals have as diverse personalities as the humans they interact with. Also evident is the amount of research Gruen conducted on train circuses. The use of photos of actual performers from period circuses adds to both the tone and realism of the story.

Honestly so much more could be said but then you'd miss out on all this fantastic book has to offer.

EAAPP 2009

So let's go back to August and the second conference that I attended in Tanzania. From August 16-21st the 2nd biannual conference of the East African Association for Palaeoanthropology and Palaeontology (EAAPP) convened.It was a traditional scientific conference with speakers from Canada (us!), the United States, Australia, Japan, Eritrea, Ethiopia, Kenya, Tanzania, and South Africa (to name a few). It was great to be able to meet so many interesting and talented researchers in the East African community and to also see again many people I'd met last summer at the Society for Africanist Archaeology meeting in Frankfurt, Germany.

The first morning kicked off with an address by Dr. Richard Leakey. This was one of the many highlights of the conference. It was absolutely thrilling to hear him speak. He pulled no punches and addressed a number of key issues including the division amongst the researchers who currently work at Olduvai Gorge, and the need for evolution to be taught in South African school. His proclamation that "fossils are not theory, fossils are fact" drew a hearty round of applause.

My supervisor, myself, and her three other students all presented at EAAPP, and as with the Zinj conference, our research program was well received. I must admit I love giving conference presentations. There is just something about standing up there and putting yourself and your research out there.

The absolute highlight of the conference was the trip out to Olduvai Gorge. It's probably sacreligious to say this but for anthropologists in general going to Olduvai is like making pilgrimage to Mecca. We were given a guided tour of both the FLK Zinj(where Dr. Mary Leakey found Zinjanthropus/Paranthropus boisei) and FLK NN site.




Although, on further reflection, discussing what it means to be an Edmontonian and Canadian while arguing about the validity of the SASES system over drinks with my buddy Ben, Dr. Ambrose, and Dr. Conard was pretty special too.

Not very good at this blog thing.

Ok so I started this blog as I felt I wasn't able to really talk about my research and my travels very well using the limited formats of Facebook and Twitter. Don't get me wrong, I love trying to think of clever things to say in 140 characters or less but I love even more the idea of integrating text with video or photos. The problem is me. I could give you a number of excuses but ultimately it comes down to me choosing to do other things. I do want to have a blog though but feel like I'm not doing it justice unless I post regularly. So here's the plan: regular weekly posts. I'm thinking Thursdays as I usually don't have anything going on. I'm already starting to sketch out the next few posts as I figure if I can stay a week ahead then it will be easier to make a routine out of it. If you could do me the favour of counting this as my first official Thursday post I'd really appreciate it ; )

Zinj Conference

In honour of the golden anniversaries of the discovery of Zinanthropus and the establishment of Serengeti National Park and Ngorongoro Conservation Area, the Ministry of Natural Resources and Tourism (home to the Department of Antiquites) decided to host a conference. We (my supervisor and her graduate students) were lucky enough to be invited as participants. To be honest, there was some confusion surrounding this conference and our plans to present in Arusha. We first found out about the Zinjanthropus (affectionately known as "Zinj") conference last summer at a stop into the Department of Antiquities in Dar es Salaam. At that time it was mentioned that it was likely that the Zinj celebration would take the form of a conference held in conjunction with the 2nd East African Association for Palaeoanthropology and Palaeontology (EAAPP) meeting planned for August 2009 in Arusha. To make a long story short, it turned out this was not the case and so we find ourselves attending both the Zinj conference (13th to 17th) and the EAAPP conference (17th to 20th).

The conference was held in the Arusha International Conference Center (AICC) which interestingly is also home to the the International Criminal Tribunal for Rwanda, judging those responsible for the genocide, crimes against humanity and war crimes (note: trials are still in progress and when in session you can sit in on them).

The first day of the conference was all about dignitaries and Olduvai (Oldupai) Gorge. It was an interesting mix of welcoming speeches, votes of thanks, and scientific papers. There was also a performance of a song written about Olduvai Gorge and Tanzania's cultural heritage. It was very heartfelt and very Tanzanian. The participants were mostly Tanzanian - government officials, tourism agents, secondary school and university students, researchers, and Masai. We were part of around a dozen foreign researchers present which is quite humbling, and we were very honoured to be included.

Gotta love free conference loot!

The rest of the conference was filled with papers and endless hours of discussion. It is hard to summarize just how important cultural heritage is here but also how much Tanzanian's love to argue/discuss. It is also a reflection of Tanzania's socialist past as everyone is allowed, and given time, to present their opinion. This meant that more often than not we were running behind.

Although the official language of the conference was English, many chose to give papers (the text in their presentations were English so I usually could still follow along) and the discussion was primarily in Kiswahili. Topics focused mostly on either the archaeology of Olduvai Gorge and Laetoli or Cultural Heritage Management - everything from new interpretations of the faunal assemblage at BK site to the ecology of Serengeti National Park to conservation and preservation of rock art sites in Kondoa. My supervisor presented an overview of our research project and it was extremely well received. In particular everyone seemed really impressed with our work with local peoples and loved the posters I created to help in the dissemination of our results in local villages, schools, offices, and museums.

All in all it was a great conference. I heard a lot of interesting talks and met some fantastic people. I left feeling very optimistic about ongoing and future work in Tanzania.

My Research 101

Good evening class. Today's topic is my research. I will try to keep this relatively short and straightforward but please do not hesitate to interrupt should you have a question. Let's begin.

I study the raw materials used to make stone tools. Specifically I am interested in the characterization (description) and sourcing of these lithic raw materials in order to infer mobility patterns, trade and exchange, and resource exploitation. Basically, I look at and describe the different types of raw materials (including, but not limited to, chert) found in stone artifact assemblages and try to determine how they were being used and where they come from.The goal of this is to go from looking at stone artifacts to actually saying something about the behaviour, culture, and worldview of the people who made them.

In particular I am intrigued by the use of chert. Chert is, well, awesome. In the real world, it is just a type of sedimentary rock and, in honour of my pledge to keep this simple, a "variant" of chert - jasper - is often considered semi-precious and is used in jewelry. In my world, chert is a highly variable, high quality raw material for making tools. Different outcrops (sources) of chert can vary significantly from other sources in the same region. This means, in theory, that I can look at the different types of chert recovered in an assemblage at a single site, and between sites, to answer a number of questions relating to technology. To get a bit more science-y, chert is fascinating because geologists still cannot quite agree over how it forms. Generally it is agreed that there is some sort of precipitation and lithification process that involves siliceous microorganisms. Often we can find microfossils which are incorporated into the chert during formation. These microfossils can be specific to particular formations which can assist in determine what source a chert is coming from. Neat huh!?

Back to my current research...I am looking at the raw materials from two stone age sites in Tanzania. I am conducting work on sites there as Tanzania is important in terms of human evolution. Both genetic and fossil evidence place the origin of our species, Homo sapiens sapiens (anatomically modern humans), to East Africa. Now there is a whole bunch of discussion in the Africanist world about the relationship between anatomical modernity and behavioural modernity. As we know when we became anatomically modern (around 300,000 years ago give or take a couple thousand years) the question is when did we start behaving like modern humans. Now there is a whole grocery list of features that are argued make up behavioural modernity (i.e. art, personal adornment, etc.). Most of these indicators were derived from European Upper Palaeolithic assemblages - sites dating to after the expansion of modern humans into Eurasia from Africa (note: there is a counter argument to the idea that modern humans evolved in Africa but it is currently not the dominant paradigm. I will have to leave that debate to another post). What this suggests is that behavioural modernity developed after anatomical modernity. For those of us working in East Africa one of the things we are trying to do is identify these indicators or traits in our assemblages and see if we can pin down when the transition to modernity occurs. Luckily our research area Iringa (see earlier post) has sites that date to the period when we see the rise of anatomical modernity, and, hopefully, also contain the period of transition to behavioural modernity.

If you are following me so far you are probably wondering how this directly relates to what I do (i.e. all the stuff with the rocks and chert). Well, it is argued that a key modern behaviour is the establishment and maintenance of long distance trade and exchange networks. By looking at where and how stone raw materials were acquired and used, it may be possible for me to infer if there were long distance trade/exchange networks. My analyses demonstrate the presence of a number of the behaviours attributed to modern humans.

Obviously my research is just one small part of the larger research project headed by my PhD supervisor, and there are other archaeologists and palaeoanthropologists from around the world who are also working on this time period and these questions. In general, those of us looking at these questions have found that in fact behavioural modernity did develop before our anatomically modern ancestors left Africa to populate the rest of the world.

Any questions?

Class dismissed.

Counting the sleeps

I leave on the 10th for another trip to Tanzania. This will be my third time travelling there in four years. I spent six weeks there in 2006 and almost three months in 2008 doing archaeological field work as part of my PhD research. It did not take me long to fall in love with everything about the country. I must admit part of me can't help but think that somewhere in all our DNA is a code which recognizes East Africa as our ancestral home. A few colleagues of mine have commented on this so I know I am not the only one who has felt this connection.

Our study area is called Iringa, and our base of operations is Iringa town. We always stay at the Isimila Hotel (named after the famous Early Stone Age site of Isimila). It is my home away from home in Tanzania. I know the menu of the hotel restaurant by rote, as well as the names of most of the people who work there. Some of the shop ladies along "the gauntlet" (a street full of souvenier shops for mzungu like me) recognize me and we joke around as I make my purchases. We joke with the parking pass guy at the central market. When not in town, we are bombing around the region stopping in at villages and talking with everyone and anyone about "caves" that they know about. Often we will pick up a few people who will take us to sites they know or have heard about. We spend hours greeting local officials from every branch of government and handout posters about our research in English and kiswahili to offices, schools, and anyone else who may be interested. We record new sites and revisit those which have been disturbed by pothunters. Mostly I smile and try my best to the swahili I am slowly picking up.

This trip will be very different from the last two though. Unfortunately there will be no fieldwork, no Iringa, no Isimila hotel this time. Instead we (myself, my supervisor, and three of her graduate students) are travelling to Arusha for two conferences. The first is a celebration of the golden anniversary of the discovery of Zinjanthropus boisei at Olduvai Gorge. I am presenting at the meeting of the East African Association of Palaeoanthropologists and Palaeontologists. Both will feature many prominent archaeologists, geologists, and palaeontologists working in the area. I am eager to talk and network with my Africanist colleagues, and hear about all the exciting work going on. My ego is looking forward to presenting though it would be better if I had something more conclusive to put forward and not just preliminary results/thoughts. Oh well.

After the conferences, we are off on a four day safari (swahili for journey, trip, expedition)through the northern parks. It is sure to be the highlight of the trip and I plan on taking hundreds of photos of the wanyama (animals).

Seven more sleeps...

Welcome to Mental Debitage

Mental:
- Adjective
1. Of or relating to the mind; intellectual: mental powers.
2. Executed or performed by the mind; existing in the mind: mental images of happy times.
3. Of, relating to, or affected by a disorder of the mind.
4. Intended for treatment of people affected with disorders of the mind.
5. Of or relating to telepathy or mind reading.
- Slang
6. Emotionally upset; crazed: got mental when he saw the dent in his new car.
7. Offensive Slang Mentally or psychologically disturbed.
- Origin
Middle English, from Old French, from Late Latin mentālis, from Latin mēns, ment-, mind; see men-1 in Indo-European roots.

Debitage:
–noun Archaeology
1. lithic debris and discards found at the sites where stone tools and weapons were made.
- Origin
< F débitage, equiv. to débit(er) to cut up, saw up (< dé- + -biter, v. deriv. of bitte bitt) + -age.


Mental Debitage:
1. thought debris and discard found on the web, result of excess meditation on topics relating to archaeology, being a student, and life.
-Origin
The mind of one Katie M. Biittner, currently a PhD candidate (ABD) in Anthropology (Archaeology) at the University of Alberta.