MicroCT Rotating Target and a Holiday Fruit Cake

In the Sustainable Archaeology Ancient Images Lab, we've been performing proof of concept tests using the rotating target on the microCT. The rotating target enables the user to "up" the flux (amount of power) that can be delivered to the target, without degrading the spot size - essentially allowing for faster scanning without compromising the excellent resolution of the machine. This give us the ability to greatly increase the amount of power we can use in a scan, allowing us to scan very dense objects, including meteorites, or, holiday fruit cake!

Special thank you to Hope Miles for providing the delicious fruit cake!

Happy Holidays from Sustainable Archaeology

This week wraps up the end of the year for Sustainable Archaeology, and marks the project's third holiday season. Two years ago (December 2012) building of the facility was delayed by the heavy snowfall that buried London early in the month, and the materials for the pre-fab building had only just arrived before the Christmas break. In 2011, we had only had occupancy of the building for a few months, and while things were really starting to wrap up in terms of the facility's construction, without furniture, or most of our major lab equipment, it still felt quite empty and unoccupied in the new building. As of December 2012, SA-Western has been occupied for over a year, and with the additions of furniture, imaging equipment, as well as staff, students, and other researchers working in the building on a regular basis, this December couldn't feel more different!

In 2013, we're looking forward to the continued development of our database, and to exciting new projects by students and other researchers. We'll continue to publish our bi-monthly newsletter, Notes from the SA and look forward to sharing more projects, research and updates from Sustainable Archaeology with you during the coming year. Until then, we'd like to wish everyone a safe and happy holiday, and best wishes for 2013!

Notes from the SA - December/January Edition

The December 2012/January 2013 edition of Notes from the SA, our Sustainable Archaeology newsletter is out!

 

3D Printer Demos

 

One of these items is the real thing - the other has been printed on a ZPrinter (450 model) from Zcorp. Can you tell which is which? The bottle, complete with threads (and fitted cap) and colour label is the printed object.

This week we attended vendor demonstrations by Cimetrix Solutions and Agile Manufacturing for 3D printers as we prepare to purchase this equipment for SA Western. The equipment will be used to print a variety of archaeological materials in 3D, including artifacts scanned using SA's 3D digitizers. 3D printers are widely used in the worlds of manufacturing and prototyping, for everything from machine components to jewellery, to chocolate - even GIS data can be used to print 3D models of landscapes. 

Digital Artifact Ecosystems: The "Internet of Things" in Archaeology

The video below features the paper "Digital Artifact Ecosystems: The "Internet of Things" in Archaeology" (Namir Ahmed, Michael Carter, Neal Ferris) presented by Western University MA student Namir Ahmed at the Digital Engagement in Archaeology conference this past week. The conference ran November 8th and 9th at the UCL Institute of Archaeology in London, England.

Other videos from the conference can be viewed at Doug's Archaeology blog. Thanks to Doug for posting these! To see conversations and chatter from the conference, check out the hashtag #digipubarch on Twitter.

Front entrance sign

 

We had our Sustainable Archaeology, Western, exterior sign erected today - now you'll know where to find us!

Yes the Cat: A Study of Mummification

The "Yes the Cat" project is an interdisciplinary investigation led by Dr. Andrew Nelson of the Department of Anthropology at Western University. The project is an ongoing study of the effects of mummification on different tissues of the body as demonstrated by the individual of interest - a domestic house cat named Yes.

Yes was mummified at the request of his owner, after dying of natural causes eight years ago. Since the time of the mummification, he has been studied using MR and clinical CT imaging in order to see beneath the exterior wrappings, to examine how the remains have changed over time.

Most recently, Yes the Cat was scanned using Sustainable Archaeology's microCT scanner. The microCT provides an additional means to non-destructively examine Yes the Cat's "afterlife", without removing any of the wrappings or disturbing the remains below. In the video below, Yes's skeleton was isolated from the layers of wrappings, which are digitally removed, allowing for the examination of the skeletal remains.

                                     

 

By isolating different densities, the researchers were also able to examine the condition of remaining internal organs, such as the heart, seen in red in the image below.

This cross-section, produced using the SA microCT's software, provides a more complete picture of Yes - through the wrappings down to the skeleton, also revealing what remains of the brain, heart and tongue.

Through digital imaging, Yes the Cat will continue to be a source of information about the effects of mummification for years to come, contributing broadly to our understanding of mummification and how mummified remains change over time. These findings can be applied to other cases of mummification, including both humans and other animals.

The Yes the Cat project will be presented at the upcoming Annual Meeting of the Canadian Association for Physical Anthropology at the University of Victoria in Victoria, B.C., on November 13th.

Guest Blog #3: From the Field to the Lab: Artifacts and “Microfacts” from the McMaster Archaeological Field School

Our third guest blog features the Centre for Sustainable Archaeology at McMaster University in Hamilton, ON. This post was written by Jennifer Walton, a third year anthropology student at McMaster, and Research Assistant at Sustainable Archaeology. The blog features her experience using the Centre's materials analysis equipment to examine "microfacts" recovered from the McMaster field school at the Nursery Site (AhGx-8) this past spring.

From the Field to the Lab: Artifacts and “Microfacts” from the McMaster Archaeological Field School

 By:  Jennifer Walton, Honours Anthropology (III), Research Assistant, Centre for Sustainable Archaeology at McMaster Innovation Park

This spring I had the opportunity to attend the McMaster University archaeological field school held at the Nursery Site (AhGx-8) in Cootes Paradise within the Royal Botanical Gardens. The site dates from approximately 3000 years ago and was also used as a farmstead during the historic era.  During the course of the excavation, we were responsible for conducting two different types of sub-surface surveys to find the boundaries of the site and to evaluate the differences between traditional test-pitting used in cultural resource management, and a finer resolution method.  Each student took standard test-pit samples using a shovel alongside bucket-auger samples to analyze the variability in field survey methods.  Understanding the variability in the recovery of artifacts using different techniques is important because of the history of plowing at the site, and the fragmented nature of the artifacts we recovered.  Test-pit sediment was screened in the field, following the guidelines set by the Ministry of Culture. The auger samples were later wet-screened at the Centre for Sustainable Archaeology at McMaster Innovation Park.

Using the auger at the 2012 field school

Auger sampling has been used at the Nursery Site since the 2010 field school. Since the site has been a plough zone for over 50 years, the Nursery Site had experienced heavy disturbances, resulting in the fragmentation of many of the artifacts. Auger sampling is useful in this context because it retains the entire sediment sample and the finer screening method allows for the collection of smaller artifacts, often resulting in more artifacts per litre of soil compared to traditional test pitting.  The boundaries of a site should show a decrease in artifact density as one moves away from the central area of the site, therefore augering is potentially a more effective way of finding the outer limits of the activity area, especially in highly disturbed areas. 

The bucket-auger sampling method uses a hand held device (7.5cm bucket-auger) that is twisted into the ground below the sub-soil to extract an intact sediment sample. All of the sediment is retained, and once in the Sustainable Archaeology lab, each auger sample is washed through 2mm mesh, dried, and the sediment fraction >2mm is examined beneath a stereomicroscope. The sediment from the test pits, in contrast, is screened in the field through 1/8 inch mesh and artifacts are picked in the field. It is the difference in these screening methods, in association with the methods used to identify artifacts that accounts for the variance in artifact recovery.

In the lab the auger samples were wet-screened, and the remaining fraction was viewed under a Zeiss V8 microscope at 10 X magnification to distinguish if the materials were, in fact “micro” artifacts.  Many research questions can be answered from the analysis of these samples, such as artifact densities and types of artifacts found in specific areas of the site or throughout the site as a whole.  Site boundaries may also be estimated and further insight into disturbance levels may be gained. The results from the auger samples have shown new insights into the artifact densities as well as the extreme fragmentation of the artifacts, especially calcined bone, ceramics and tertiary debitage.  Using this survey method and the resources at the Centre for Sustainable Archaeology has allowed us to identify new areas of the site which can be excavated in future field seasons.

Examples of the "microartifacts" found in the auger samples, using a Zeiss V.16 axiozoom telecentric microscope at 20 X magnification. From left to right: historic era ceramic; tertiary debitage; calcined bone; pre-contact ceramic)

 

Signs, Signs, Everywhere There's Signs!

It's been a while since we've had a construction or building related post to share! Today we received our official signage, including room numbers and designations, as well as a number of exterior signs. It's one of those finishing touches that makes the building really feel polished and functional.

Notes from the SA

We'd like to take this opportunity to share our newest endeavour:  Notes from the SA: The Sustainable Archaeology Newsletter. Our goal is to connect with fellow researchers and with students both in the archaeological community, and on campus at Western. If you have ideas for content, events, lectures, conferences or grants you'd like to share, contact Kira Westby at kwestby2@uwo.ca

Guest Blog #2: Animating the Past

Our second guest blog features the experiences of Colin Creamer during his participation in the Sustainable Archaeology Animation Unit internship this summer. Colin is a recent graduate of the Loyalist College Animation and New Media program, and was recently hired by Sustainable Archaeology. 

Animating the Past 

By Colin Creamer

As animators we come from an artistic and tech-savvy background and look at the world much differently than archaeologists might. We had very little knowledge of the world of archaeology. When we discovered we could come all the way down to London from Loyalist College in Belleville, to work at a museum, it wasn’t so much the history and knowledge of the past that caught our attention, but more so the opportunity to get hands-on experience with new technologies. At Loyalist College this past year, we were just beginning to get into some of the freeware scanning solutions such as Autodesk’s 123D Catch, an image driven 3D reconstruction platform. It was really cool to see real-life objects come into digital existence. However with this platform, being a beta, you got whatever it gave you and had no real control over the results. Sometimes it worked, but most of the time you would get some deformity that resembles nothing of the original object being scanned. This made the idea of working with the-real-deal industrial grade scanners all the more appealing.

Colin Creamer sets up an artifact scan

After jumping the fence and zipping down to London, we started our work term with the Sustainable Archaeology Animation Unit (SAAU). May 7th 2012 was our first day. We got the tour of the facility, and were in awe as we saw the massive mechanical aisles of the artifact repository sliding across the floor. To think, these shelving units would soon be the home of hundreds of thousands of artifacts in the near future. We would be a part of that process, scanning a variety of artifacts for digital archiving. Unfortunately… there was one problem. Things were only just starting to come together. The scanners would not be arriving for at least another three weeks. So now there’s a room full of animators, but nothing to do. We needed a project to keep us occupied and seeing as we are animators after all, the idea sprouted to create a recreation animation of the Lawson Village site, a 16th century Neutral Iroquoian site, located just outside the facility, next door at the Museum of Ontario Archaeology.


 The animation of the village would give an understanding to interested onlookers. However seeing as none of us animators are archaeologists; in order to pursue this new project, we needed to develop an understanding of what archaeology is and learn as much as we could about the Lawson site. The animation had to appeal to people that have little or no understanding of archaeological findings. Also on the other hand, each archaeologist has their own interpretation of what a village site would look like, and we had to show something that was accurate. Throughout the term we were learning new things little by little. At first, we went out to do some concept art in the site, and draw anything and everything we saw. We also obtained archaeological maps which illustrated the shape of the land as well as features that showed exactly where the long houses and palisade posts resided. This allowed us to build an accurate representation of the site layout. We also went on a field trip to the Ska-Nah-Doht Village and Museum site, to get a better general understanding of how things were thought to have been at the time that the Lawson Site was occupied. All of this research informed how we designed and created the animation.

 Having started with no insight or real knowledge of archaeology, working at the museum on related projects has bridged the gap between two, normally unrelated fields. The experience is continually exposing us to the terminologies and ways of archaeology. This unique mix has allowed us to successfully achieve projects such as the Lawson animation, that both people from inside and out of archaeology can appreciate and enjoy.

Autumn at the Lawson site

 

It's a beautiful fall day out in the reconstructed late Woodland village beside SA Western. Inside, the microCT is busy scanning primate skulls and plans for the database are taking shape up in the Mezzanine. This month we anticipate researchers on site to utilize our equipment for analyzing coral growth and trauma caused by hanging. We will also receive our second shipment of green boxes. We expect to be accepting collections into the facility by late spring/early summer. If you require any boxes for collections that you anticipate storing at SA Western, please contact SA Operations: rhonda.bathurst@uwo.ca

What Can We Learn About Ceramics?

Examining digital scans of archaeological artifacts can tell us how an object was made, what materials it was constructed from, how it was used, how it was broken or mended, or how it has changed over time. Digital scans can aid in identification of materials, or in plans for conservation. Through past blog posts and videos, we've demonstrated the capabilities of Sustainable Archaeology's MicroCT scanner for digital analysis and non-destructive studies of a range of archaeological materials. We've demonstrated the potential for examining pathologies (evidence of past injury or disease) in bone, and for revealing previously unknown aspects of artifacts - from what lies below the rust of a metal object, to what the interior of a historic pipe looks like. This week, we turn to ceramic material, and to what a digital scan of a ceramic object can reveal.

Happy Anniversary to Western SA!

Today marks the first year anniversary of Western's SA occupancy permit. Over the course of this past year, we've seen the finishing touches done to the building, had our safety checks and we've purchased our computers, 3D scanners, MicroCT, digital x-ray and an electric work assist vehicle.We've hosted a three month 3D/animation internship and a three week thin-sectioning workshop. Our geophysical equipment has been used at a number of archaeological sites, including at Techumseh Park in Chatham, Ontario (last September), and at Fort Erie this summer. We've welcomed tours of representatives from the Canadian Foundation for Innovation, the First Nation's Financial Management Board, the Smithsonian Institution, the Art Gallery of Ontario, Mitacs, local Rotary clubs, as well as hosts of individuals from across Ontario and around the world who are interested in Sustainable Archaeology and the philosophy we espouse. We've also begun to establish communication with a variety of other archaeological facilities and institutions, such as the Center for Digital Archaeology at the University of California, Berkley.

Over the course of the next year, we look forward to growing and settling into our space. We have more equipment to purchase (including a 3D prototyper and Virtual Imaging station), more courses and workshops to host, and we're looking forward to having some substantive information to share about our project at a number of local and international conferences. Watch for representatives from SA Western and SA McMaster at the Ontario Archaeological Society meeting in Windsor and the Canadian Association for Physical Anthropology conference in Victoria, BC in November 2012, as well as the Society for American Archaeology conference in Honolulu, Hawaii in April 2013! 

Guest Blog: Don’t look a gift horse in the mouth? How about looking at 170 digital radiographs of deer mouths!

This week we are featuring a guest blog post by Zoe Morris, a PhD candidate at Western University, and our Ancient Images Lab technician. You may remember Zoe from some of our past blog entries, featuring artifact scanning and proof of concept testing on the MicroCT. In this post, she introduces one aspect of the research she has completed for her PhD thesis - determining the order of tooth formation (dental mineralization) in white tailed deer. Her research has been informed by examining radiographs (x-rays) of deer jaw bones completed at Sustainable Archaeology using the Faxitron Digital X-Ray. Why deer? Read on to find out!

Don’t look a gift horse in the mouth? How about looking at 170 digital radiographs of deer mouths! 
By Zoe Morris, PhD Candidate Department of Anthropology, Western University

White-tailed deer are one of the most adaptable North American mammalian species, found as far south as the jungles of Central America and as far north as the boreal forests south of Hudson Bay. They are the most important Canadian and American hunted species, providing millions of dollars in revenue annually. White-tailed deer are also significant crop pests, causing more damage to crops than any other large-bodied animal, they are involved in thousands of deer-car collisions a year causing property damage and human loss of life and they can be vectors for a variety of diseases that affect livestock.

A browsing white-tailed deer in the Medway Valley Heritage Forest, neighbouring the Sustainable Archaeology facility in London. Photo by Zoe Morris.

White-tailed deer’s adaptability to human altered landscapes has brought them in close proximity with humans for thousands of years and they are the most ubiquitous animal find at many North American archaeological sites, constituting a major source of protein and an essential source of skins for clothing and shelter for past human groups.  Because of the modern and archaeological significance of white-tailed deer, understanding their habitat-use throughout the year has implications for ecological research, hunting policies, and archaeological understanding of past life-ways.

In order to better track the movement and diet of Ontario white-tailed deer over the first year and a half of life, I determined the dental mineralization sequence of white-tailed deer teeth.  There is extensive literature on the order of eruption of white-tailed deer teeth and this information is used by hunters, ecologists and zooarchaeologist to estimate the age of deer under two years old (dental wear is used after two years of age).  However, there is no previous research on the mineralization sequence for white-tailed deer.

In order to examine dental mineralization I examined 170 radiographs (x-ray images) of juvenile (less than two years), Ontario white-tailed deer mandibles and maxilla.  The majority of radiographs were completed at the Sustainable Archaeology Ancient Images Laboratory located in London Ontario. Additional radiographs were completed at the Royal Ontario Museum in Toronto, Ontario and Canadian Museum of Nature in Gatineau, Quebec.

All of the radiographed deer were aged based on their dental eruption. I also estimated their season of death. For example, most deer in SW Ontario are born mid-May or early-June. Therefore if a white-tailed deer died at six months old, it probably died approximately November. We could then begin to work out when each tooth was forming by examining the radiographic images and estimating which teeth were forming during which season. (Left image: sixteen white-tailed deer mandibles at various dental mineralization stages. Digital Radiograph courtesy of Sustainable Archaeology Ancient Images Laboratory).

Once the dental formation sequence was completed, it was confirmed using oxygen isotope analysis. Oxygen isotopes were obtained from the serial sections of deer teeth. Oxygen isotopes are variations of oxygen atoms whose ratios vary depending on factors such as temperature, precipitation, and geography.  This ratio is preserved in tissues such as dental enamel.  Because precipitation and temperature varies greatly in SW Ontario with season, we were able to track seasonal variations in the oxygen of both modern and archaeological deer teeth. Happily, the variation corresponded to the estimated season of dental formation!

Why is this significant? We can now use those same teeth to track other information about white-tailed deer. For example, I was able to examine whether deer were eating corn or other food sources during the first two years of life using carbon isotopes from the dentition. Carbon isotopes reflect the foods we eat and can vary based on whether a plant is warm weather adapted (like corn which was domesticated in Mexico) or cool weather adapted (like most indigenous SW Ontario plants).  For more information on the final results of this study, please see my dissertation, to be defended in 2013 (fingers crossed).

A white-tailed deer skull with mandibles (~six month old) from Griffith Island, Ontario. Note the second molar is forming but has not yet erupted.  Digital Radiograph courtesy of Sustainable Archaeology Ancient Images Laboratory