Digital Marine Osteoarchaeology: The problematization of bodies and bones in water

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Department of Archaeology and Ancient History

Digital marine osteoarchaeology

- the problematization of bodies and bones in water

Matilda Fredriksson

Master's thesis, 45 ECT's, spring 2017 Uppsala University Campus Gotland Supervisor: Sabine Sten Co-Supervisor: Johan Rönnby

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Cover photo of the diver and photographer Ingemar Lundgren at the Gribshunden site by the author.

All pictures and illustrations in this thesis are by the author unless anything else is stated.

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ABSTRACT

Fredriksson, M. 2017. Digital marine osteoarchaeology: the problematization of bodies and bones in water

Fredriksson, M. 2017. Digital marinosteoarkeologi: problematiseringen om kroppar och ben i vatten

This master's thesis is intended as a foundation for further development of methods for digital marine osteoarchaeology. The main purpose of this thesis was to examine and problematise the process of locating, documenting, and analyzing skeletal remains in marine archaeological, and other hard to reach sites. Three forms of osteological analysis' was performed and assessed: one based on analysis of physical skeletal remains, another based on 2D documented skeletal remains, and a third on analysis on 3D reconstructed skeletal remains. The secondary purpose of this thesis was to problematise the taphonomic effects on bodies, body parts, and bones in marine environments, necessary for the evaluation of the different methods. The analysis' has been conducted on source material provided by the research projects for the naval ships Mars and Gribshunden, the National Maritime Museum of Sweden, the Sandby Borg project, and the Çatalhöyük project. In addition, a test was carried out, with eight volunteer osteology students at Campus Gotland, Uppsala University, during a seminar exercise. The results collected through the osteological analysis' performed on the three different formats and the students osteology exercise could be used in order to highlight a variation of data available in the different formats. The results was then used in order to create a basis for future digital documentation methods that may be applied in the field. The secondary aim of this thesis was addressed through the use of the naval ships Mars and Gribshunden as case examples in order to address the limited amount of skeletal remains located so far at the marine archaeological sites.

Denna master uppsats är ämnad som grund för vidare utveckling av metoder för digital marinosteoarkeologi. Det huvudsakliga syftet med uppsatsen är att undersöka och problematisera problemen kring at lokalisera, dokumentera, och analysera skeletala kvarlevor vid marinarkeologiska, och andra svåråtkomliga lokaler. Tre olika slags osteologiska analyser utfördes: en baserad på analyser av skeletala kvarlevor, en annan baserad analyser av 2D dokumenterade skeletala kvarlevor, och en tredje baserat på analyser av 3D rekonstruerade skeletala kvarlevor. Det sekundära syftet uppsatsen var att problematisera den tafonomiska påverkan på kroppar, kroppsdelar, och ben i marina miljöer, nödvändiga för utvärderingen för de olika metoderna. Analyserna har utförts på källmaterial som tillgängliggjorts genom forskningsprojekten för skeppen Mars och Gribshunden, Statens Maritima Museer i Sverige, Sandby borg projektet, och Catalhöyük projektet. Utöver detta har även en studie utförts tillsammans med åtta frivilliga osteologistudenter vid Campus Gotland, Uppsala Universitet, under en seminarieövning. Resultaten som samlades in genom de osteologiska analyserna av de tre olika källmaterialen och student studien användes för att kunna understryka den datavariation som fanns tillgänglig för de olika källmaterialen. Resultaten användes för att skapa en grund för framtida digitala dokumentationsmetoder som kan appliceras i fält. Det sekundära syftet med studien besvarades genom att använda skeppen Mars och Gribshunden som exempel för att kunna diskutera den begränsade mängden skeletala kvarlevor som hittills hittats vid de marinarkeologiska lokalerna.

Master's thesis in Archaeology with focus in osteology 45 ECT's. Supervisor: Sabine Sten. Co- Supervisor: Johan Rönnby. Ventilated and passed [June 2^nd 2017] © Matilda Fredriksson. Uppsala University Campus Gotland, Cramér gatan 3, 621 57 Visby, Sweden.

Keywords: Digital marine osteoarchaeology; Marine archaeology; Marine osteology;

Osteoarchaeology; Bioarchaeology; Birka; Mars; Gribshunden; Mary Rose; Sandby borg; Çatalhöyük;

Marine osteoarchaeology; Animal remains; Human remains; Taphonomy; Fluvial transport.

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Acknowledgments

A great thank you to ...

My supervisor Sabine Sten, professor at Uppsala University Campus Gotland, for all the help and support that you have given me through the years. You showed me the world of marine osteoarchaeology, and through this you helped me find a way to combine two of the things that fascinate me the most, osteology and digital photography. For this and much more, I am forever grateful.

My co-supervisor Johan Rönnby, professor at Södertörn University, for all the help and support you have given me through the years. You did not only invite me into the world of marine archaeology, but you also showed me that research may be an adventure when part of a good team.

The project groups for the research projects for the naval ships Mars (1564) and Gribshunden (1495), for letting me be a part of these two amazing projects. You have all taught me so much, and I look forward to many more exciting and lucrative meetings with you in the future.

All the archaeology and osteology teachers at Uppsala University Campus Gotland, and the archaeology teachers at the masters program at Uppsala University, for passionately guiding us students through the wonderful world of archaeology, for all the hours of hard work that you do, and for never leaving a question unanswered.

Nina Eklöf, marine archaeologist at the Swedish Maritime Museum, for inviting me to the maritime Birka project, as well as supporting and aiding me in my search of taphonomic changes in the animal remains of the Viking Age harbour of Birka.

Anneli Ekblom, PhD, Uppsala University, for all the advice and support you have given me, concerning my thesis, during the last two years.

Ian Hodder, professor at Stanford University, USA, for the lucrative discussion concerning my thesis work and for providing me with articles concerning the digital documentation at Çatalhöyük, as well as granting me access to part of your digital material.

Scott Haddow, PhD, Editing assistant at Stanford University, USA, for providing me with both answers and articles concerning the digital documentation at Çatalhöyük, as well as granting me access to part of your digital material.

Alex Hildred, PhD, at the Mary Rose museum, England, for granting me access to the collection, answering my questions concerning the remains and their taphonomic conditions, and for the discussions concerning future possibilities.

Simon Ware, Collectors assistant at the Mary Rose museum, England, for granting me access to the collection and answering my questions concerning the remains and their taphonomic

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conditions.

Max Jahrehorn, conservator at Oxider AB, for the long and interesting discussions concerning the disintegration and taphonomic effects on human bodies and skeletal remains in marine environments.

Fredrik Gunnarsson, archaeologist at Kalmar Länsmuseum, for providing me access to the digital documentation from the Sandby borg project.

Fredrik Svanberg, head of the Swedish Maritime Museum's dive unit, for granting me continued access to the animal skeletal remains of the Viking Age harbour of Birka.

Jhonny Therus, PhD student at Uppsala University, for the lucrative discussions concerning the use of the digital documentation collected at the Sandby borg site, as a comparative material for my thesis.

Leena Drenzel, first curator at the Swedish History Museum, for letting me use the Swedish History Museum's reference collection and aiding me with the species assessment for some of the more complicated bone elements.

Jim Hansson, marine archaeologist at the Swedish Maritime Museum's dive unit, for the lucrative discussions concerning the possibilities of applying the digital method in both archaeological and forensic contexts.

Clara Alfsdotter, PhD student at Grasca and archaeologist at Bohuslän museum, for all the support and discussions concerning the skeletal remains at the Sandby borg excavation, and advice prior to my visit at the Mary Rose museum.

The osteology students at Uppsala University Campus Gotland who participated in the osteology students exercise. Thank you all for partaking in the study and adding valuable data to my research.

The 'Kungliga Humanistiska Vetenskapssamfundet in Uppsala Enequistska medlen' for granting me a travel scholarship, and making my visit to the Mary Rose Museum in Portsmouth, England, possible.

My friends and family, for all the love and support you've given me during the last five years.

You are the wind in my sails, and the light that guides me home.

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This thesis is a continuation of a study that was initiated in my bachelor's thesis The skeletal remains of the naval ship Mars: An osteological pre-study for analysing digitally documented skeletal remains in a marine context (Fredriksson, 2015). The aim of the bachelor's thesis was to lay the ground for future osteological analysis of the skeletal remains of the naval ship Mars. The purpose of this master thesis, is to further examine the possibilities of using digital documentation to analyse skeletal remains in marine environments. I also address how to create a work method applicable in the field. A taphonomic understanding is crucial for assessing different field methods, therefore, I also study the taphonomic effects of human and animal remains focusing on the disintegration of bodies and bones in marine environments.

The study includes: fluvial transport of bodies, body parts, and separate bone elements in marine environments, as well as the absorption of foreign substances in bone tissue. The discussion concerning the fluvial transport is also connected to the limited amount of documented skeletal remains at the marine archaeological sites of the naval ships Mars and Gribshunden.

The study was based on both physical skeletal remains, digitally documented 2D remains, and 3D reconstructed skeletal remains. As a part of the study I have also carried out a student osteology exercise where a group of osteology students performed osteological analysis' on ten bone elements in both physical and digital 2D format. The skeletal remains used in the osteology students exercise consist of fragmented animal bones from the training materials in the osteological laboratory of Uppsala University Campus Gotland.

The other physical remains discussed here consist of the animal skeletal remains from the 2014 excavation at the Viking Age harbour of Birka, Sweden, and a selection of human skeletal remains of the naval ship Mary Rose, England. The digitally documented 2D skeletal remains were collected through the use of ROV (Remotely Operated Vehicle) and divers with handheld cameras at the sites of the naval ships Mars and Gribshunden in the Baltic Sea, Sweden, through the use of remote sensing documentation. The 3D reconstructions were based on the image material of skeletal remains collected during the terrestrial excavations of Sandby borg, Sweden, and Catalhöyük, Turkey.

The terrestrial 3D image material of the human skeletal remains were added as a contribution to this thesis in order to allow for further discussion concerning the possibilities and limitations of in-situ 3D reconstructions of skeletal remains as source of data collection through the use of an osteological analysis.

1.1 Purpose

The primary focus of this thesis is to further examine the possibilities and limitations of digital marine osteoarchaeology, and create a field methodology, through comparison of the amount and form of data that may be collected through the use of different types of source material. Underwater excavations are, just like conservation, expensive. Occasionally, the marine archaeological sites are placed too deep or contain artefacts or remains that are too fragile to collect, at such sites it would be ideal to be able to collect as much information as possible without disrupting the site. The development of the work method is based on the comparisons between the three types of source material, the physical skeletal remains, the 2D

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documented skeletal remains, and the 3D reconstructed skeletal remains, in order to contrast the information available to the osteologist through the different formats. In order to be able to assess these different techniques with a sufficient amount of empirical studies from a wide range of contexts are included, not only marine archaeological sites (the naval ships Mars and Gribshunden, the Viking Age harbour of Birka), but also some terrestrial sites (Çatalhöyük and Sandby borg). The comparison between the collected data from the performed osteological analysis presented here provide a basis for development of the documentation method, based on the represented osteological features available to the osteologist through the two forms of image material, 2D and 3D. In addition I have also tested results of identification using physical skeletal remains and photo imaging in a test group of students to further assess the different methods. The comparison of the information collected through the different formats may, therefore, be used in order to determine how skeletal remains preferably should be documented at marine archaeological sites in order to collect as much information as possible.

It has become clear in the research process that there is a need for a greater understanding and acknowledgement of the taphonomic processes. A secondary aim of this thesis has, therefore, been to present and discuss the taphonomic effects of human and animal skeletal remains in marine environments. This in order to create a greater understanding of how bodies and bones are transported in fluvial systems, and how this affects the amount of skeletal remains visible or present at the marine archaeological sites for the naval ships Mars and Gribshunden. These factors are of great importance within the context of digital marine osteoarchaeology since the understanding of how bodies are transported may allow researchers to pinpoint certain areas in the marine system where it is more or less likely to discover skeletal remains. The study of taphonomic effects of human and animal remains in marine environments is also done in order to create a greater understanding of how skeletal remains absorb foreign substances in the bone tissue. A greater understanding of how the bone tissue is affected by the marine environment may provide the researchers with additional information of the skeletal remains during an osteological analysis of both physical and digitally documented skeletal remains. In the end of the thesis a recommendation for designing a documentation strategy and photographic documentation is also given resulting from the study presented in this thesis.

1.2 Research questions

To summarise from the above I here address the following three main research questions:

- How do the collected data differ between a physical, 2D, and a 3D osteological analysis?

- How should the skeletal remains preferably be documented at the site in order to retrieve as much information as possible?

- How are bodies and skeletal remains affected by the marine environment? And how may this explain the lack of located skeletal remains at the sites?

The first research question was formulated in order to discuss and assess the quality of information available to the osteologist on the basis of three different methodologies: analysis' based on 2D documented skeletal remains, and analysis' on 3D reconstructed skeletal remains.

The second research question was formulated as a consequence of the results presented in the first research question. The aim is here to formulate a recommendation for the basis of a documentation method for skeletal remains at marine archaeological sites. The third research question is also an outcome of the results of the analysis' carried out connected to research question 1. The research question was formulated in order to problematise how bodies, body parts, and bone elements are affected by the marine environment. To answer this question I

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have had to compile a lengthy review as marine taphonomic processes in themselves are an under researched field within archaeology. Some of the review has been placed in the appendix. In the thesis text the aim is to explore how taphonomic factors may explain the limited amount of skeletal remains at the marine archaeological sites of the naval ships Mars and Gribshunden.

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2. SOURCE CRITICISM AND DELIMITATION

2.1 Digitally documented 2D and 3D skeletal remains

Most of the digital documentation performed at the marine archaeological sites (the naval ships Mars and Gribshunden) where collected by non-archaeology/osteology trained divers.

The lack of archaeological/ osteological training may be an important factor that affected how the divers searched for and documented the bone elements at the site. The image material collected during the first field season was taken with the aim to document the wreckage and the surrounding site, and did, therefore, not focus specifically on the documentation of specific objects.

The skeletal remains documented during the field season of 2015 were collected before the author had been contacted by the project group (the research project for the naval ship Mars) and was, therefore, documented from a limited amount of angles and without a measuring stick. The documented skeletal remains of the naval ship Mars have been documented in two different formats, film and photography, where the photography has been performed in two different ways. The majority of the images containing bone elements or possible bone elements are images where the diver has not actively documented the specific bone element, but has instead by chance taken pictures where bones or possible bones happen to be in the surrounding area. A small amount of bone elements, and possible bone elements, were documented according to the instructions given to the divers by the author during a presentation at the base camp for the 2015 naval ship Mars (1564) examinations. The instructions included the placing of a measuring stick near the bone element in order to create a size reference applicable in the osteological analysis. Recommendations were also given as to documentation angles and amount of images. The divers were urged to document the bone elements from above, as well as from all sides, and to collect as many different images as possible of each bone element in order to ensure that as many osteological characters would be available to the osteologist during the analysis in the laboratory.

A large amount of the image material was also collected for other purposes than to perform a digital osteological analysis, such as in the case of the 3D reconstructed skeletal remains at the sites Catalhöyük, Turkey, and Sandby borg, Öland, Sweden, and were included here for comparison.

Most bone elements at the Mars site were not discovered until the image material was thoroughly examined. This because of the specific diving conditions at the site where the divers had a hard time locating the skeletal remains due to limited access to light and the marine sediment cover at the site.

Unfortunately, the skeletal remains located in 2014 could not be relocated at the site in 2015. It is, therefore, possible that either the bones and/or the marine sediment had been swooped around the seabed, or carried off by undercurrents.

The author of this thesis was present as an osteoarchaeologist during the archaeological excavation at Sandby borg, Kalmar County Museum, in 2015 and assisted the main osteologist, Clara Alfsdotter, during the collection of the individual referred to as individual 2 in this thesis. The author has, therefore, knowledge of some of the osteological characters not visible in the digital 3D reconstruction of the individual. This information has not been included in this thesis since the purpose of the analysis of the digitally 3D reconstructed individuals at the Sandby borg site, is to underline the amount of information available in the actual image material, not in the ocular information collected by the author during the

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collection and handling of individual bone elements during the collection process at the site. It is, therefore, important to underline that the author has previous knowledge of the age and sex of the analysed individual.

2.2 Physical skeletal remains

The majority of the physical skeletal remains from the Viking Age harbour of Birka was analysed without the use of a physical reference collection. This since the Swedish Maritime Museum did not have access to an osteological reference collection. The bone elements were, therefore, instead compared to a number of articles and reference books of human and animal remains. Some of the bone elements were, however, analysed in the osteological reference collection at the Swedish History Museum in Stockholm.

The skeletal remains studied at the Mary Rose museum, Portsmouth, England were picked based on their exposure to foreign substances in-situ. A small selection was made for this thesis and may, therefore, not be seen as representative for all the skeletal remains at the site.

2.3 The osteology students exercise

The osteology students at Uppsala University Campus Gotland analysed animal skeletal remains in both physical and documented form (in printed digital pictures) and the results differs to a large extent between the students. The student trial was intended be performed individually, the results of the study do, however, indicate that the students discussed the different bone elements amongst themselves. Student assessments of one of the specific bone elements concur with the students seating in the two joint rooms, region A and B, in the laboratory. The results from their analysis of both the image material and the physical bone elements show that there was some discussion among the students. Sheets 1-2 were collected first in area B, whereas sheets 3-7 were collected in area A, sheet 8 had been left by a student on a table in area B instead of handed in at the assigned desk and was, therefore, collected last and given the number 8.

Bone 10, a horse femur, was during the analysis of the image material determined as the bone element as a large bovine femur by students 3, 4, 5, to small bovine femur by students 6,7. All these students were seated in region A. The three students, 1, 2, and 8, seated in region B, determined the bone to be horse (Equus caballus) femur. The physical analysis of the same bone element resulted in a slight change of species assessment. Here students 1,2,6,7, and 8 determined the bone element to be a horse femur and students 3, 4, and 5, determined the bone to a large bovine femur. Meaning that the students who determined the bone element to belong to a small bovine changed their answer concerning species from small bovine to horse. These students were seated in region A. The species determination divide between region A and B during the digital analysis of bone 10 may be of chance, but since this is an unknown factor it is of great importance to underline this as a possible contributing factor.

The collected data is, therefore, unfortunately, not representative of the individual interpretations of each bone element. However, since the image material was analysed prior to the physical skeletal remains it may be possible to draw some form of conclusion regarding the different analysis methods as will be discussed further below.

2.4 Literature limitations

There is a limited knowledge concerning taphonomic processes. There are a few books

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focusing on the theme, but most information can be retrieved from forensic articles, some of which represent archaeological perspectives. Most do, however, focus on modern forensic cases (Sorg, et al. 2006:567). Anderson and Bell (2016) underline in their article Impact of marine submergence of decomposition of Carrion that the knowledge of taphonomic effects of human bodies in water is rather limited. Most research of human remains have been conducted in terrestrial environments, whereas the marine environments have remained rather unexplored. Some observations have been done on the decomposition of marine animals, the taphonomic effects do, however, differ from the ones that have been noted on terrestrial mammals of humans or human sized animals placed in a marine context (Anderson & Bell, 2016:2). For this reason and because of the limited knowledge on marine taphonomic processes, a discussion on taphonomic processes is included here.

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3. BACKGROUND

Since several forms of source materials and sites have been used as a basis for this master's thesis, each material and site is be presented separately through a short presentation based on some of the most important factors relevant to this thesis. A short summary of the previous research is also presented in this chapter.

3.1 The naval ship Mars, Baltic Sea, Sweden

The naval ship Mars was found, in the Baltic Sea at a depth of sixty-five to seventy-five meters (Eriksson, et al. 2011:5), north east of the Island of Öland, Sweden, by Ocean Discovery in the summer of 2011. The wreckage was examined in October the same year (Rönnby, et al.. 2013:5) where the identity of the ship was confirmed through an assessment of markings found on one of the large cannons located at the site (Eriksson, et al. 2011:15).

Further archaeological surveys were conducted in the summers of 2012, 2013, 2014, and 2015, where sonar, ROV (Remotely Operated Vehicle), and divers with handheld cameras were used in order to document the wreck and any possible artefacts and remains at the site (Rönnby, et al. 2013:5; Eriksson, 2015:5; Eriksson & Rönnby, 2017:94). Three silver coins were located and salvaged during the second archaeological survey (Rönnby, et al.. 2013:5) and two canons and several wooden structures were collected during the third archaeological survey in order to evaluate possible future preservation methods (Eriksson, 2015:5). The ship sank due to an explosion in the fore ship where the black powder was stored (Smirnov, 2009:106).

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Fig 1 The naval ship Mars, Mosaic picture compilation of the wreckage. Photo by Tomasz Stachura

3.2 The naval ship Gribshunden, Ronneby, Sweden

The naval ship Gribshunden, also known as the Griffon, was located at the depth of approximately 9 meters by sport divers near the island Stora Ekön, Sweden, in the 1970's but remained undocumented until 2001 when the divers group Doppingarna contacted the Kalmar County Museum (Einarsson & Gainsford, 2007:3; Einarsson, 2008:23; Warming, 2015;

Rönnby, 2015:5-7.). Three types of marine archaeological surveys were conducted on the site;

an ocular survey, an archaeological investigation, and a sample collection. Further examinations of the site were performed in the autumn of 2006, where a small trench on 100x80x110cm was placed near the keelson of the ship. The excavation revealed finds of ceramics, glass, leather, metal, wood, and animal bones (Einarsson, 2008:37; Warming 2015;

Rönnby, 2015:5-7). The surveys at the site then continued in 2013 through a cooperation project between the MARIS Ships at war project, Blekinge Museum, and Kalmar County Museum. The cooperation project was later expanded to include the University of Southampton and the companies MMT (Maritim Mätteknik) and Combat archaeology (Warming, 2015). The figure head of the Gribshunden ship was located in June 2015, and was due to its sensitive position collected through a protective salvage attempt in August 2015.

The figure head was then sent to Blekinge museum to await conservation. Further archaeological surveys are to be conducted in cooperation of Blekinge museum, MARIS, MMT, Southampton University, The South Danish University, Kalmar County Museum, the divers club Doppingarna, Deep Sea productions, and several other volunteer colleagues and divers (Rönnby, 2015:6).

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Fig 2 Illustration of the Gribshunden wreck in-situ by Niklas Eriksson published in Marinarkeologisk Tidskrift 1. 2016.

3.3 Maritime Birka, Uppland, Sweden

The first notes of the presence of a cultural layer in the Björkö strait was made in the mid 1800s but no confirmation was made until the early 1870s when the archaeologist Hjalmar Stolpe collected soil samples from the water area in an attempt to locate trace of amber. The first marine archaeological surveys were, however, not performed until 1957 when the archaeologist Clas Varenius examined the area with the aid of British divers. New surveys were then performed in the years 1969 to 1971 by the Swedish National Maritime Museums and the Stockholm diver community in an attempt to relocate old shore lines and traces of old port structures. They noted the presence of a possible bulwark and collected wood samples that after a 14^C analysis indicated that the structure dated back to the 700’s. They also noted the presence of several jetty foundations that could be dated to the 900’s due to their position in relation to previous shore lines. Several minor surveys were performed in the Björkö strait in the 1990’s, and underlined the presence of several different harbours. Further surveys were conducted by the Swedish National Maritime Museum and Södertörn University (MARIS) in the years 2004-2014. The first survey was a preliminary investigation where the marine archaeologists excavated a 1m² area, and found a 120 cm thick cultural layer, where most of the located finds consisted of wood. The further surveys focused mainly on marine archaeological excavations where six 1m² areas were excavated in 2010, and resulted in the mapping and further understanding of the formation of the cultural layers at the site. Two trenches on a total of 12m² were excavated in the years 2011-2012 and recovered a large amount of timber, pikes, two possible stone anchors, and a cultural layer filled with well- preserved organic find material. The surveys continued in the years of 2013 and 2014, where a 6m² trench was excavated in 2013 and an approximately 6m² trench was excavated in 2014, as well as the collection of 34 drill samples and three cross sections (Olsson, in prep).

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Fig 3 The marine archaeological area examined at the Viking Age harbour of Birka in 2014.

3.4 Çatalhöyük, Anatolia, Turkey

The early Neolithic town Çatalhöyük, Anatolia, Turkey, was discovered by British archaeologists in 1958, and was first excavated in the years 1961-1965 and resulted in the discovery of 40 houses, some of which contained wall art, pottery and figurines (Çatalhöyük Research Project site). The remainder of the area remained unexamined until 1993 when Ian Hodder and his team started up their new Çatalhöyük research project (Berglund et al.

2016:434; Catalhöyük Research Project site). In 1998 two new west mound teams continued the research that was started in 1961. The excavations continued in the northern area in the years 2007-2008. In the 2010s the excavations started to become more and more digital. The traditional excavation work continued but new digital methods for documentation and visualisation started to be used (Çatalhöyük Research Project site).

The 3D reconstructions at Çatalhöyük were created through the use of regular cameras and the two softwares Meshlab and Photoscan. Each individual was documented with as many as 15-50 images from as many angles as possible in order to create as good a representation of the individual conditions of each individual grave. The aim was to through the use of the documentation avoid the timely task of manual drawings of the graves and limit the amount of exposure of the remains before being collected and sent to an osteological laboratory for further analysis. The 3D reconstructions have mainly been used in order to illustrate the conditions of the site and the placement of individual objects or skeletal remains for several different public purposes. No attempt to analyse the skeletal remains through the use of digital methods have been attempted since the remains were collected at the site (Haddow, 2012).

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Fig 4 Illustrative image from the Çatalhöyük site. Photographer: Jason Quinlan.

http://server.catalhoyuk.com/netpub/server.np?original=85048&site=catalhoyuk&catalog=catalog

3.5 Sandby borg, Öland, Sweden

The Iron Age ring fort of Sandby borg at the eastern coast of the swedish island of Öland is clearly visible in the landscape, and has been examined at several different occasions from the early 1800's to present day, where the main purpose was to examine the ring fort itself (Viberg et al., 2014:414-415). The present day excavations at the ring fort Sandby borg was, however, not initiated until 2010 after the discovery of looting pits during some initial GPR and magnetometer surveys within the fort structure. The looting pits where reported to the Kalmar County Museum who performed a metal detector survey in 2010 prior to their first excavation performed in 2011 (Viberg, et al. 2014:416).

The initial archaeological excavation by the Kalmar County Museums archaeological unit showed traces of what turned out to be a massacre that took place in the 400's. Annual excavations are performed with the aid of digital documentation techniques through the project the Digital Sandby borg. A project that includes both 3D reconstructions of the site as well as the web based portal Sandby borg - a digital discovery where the general public is allowed to follow the archaeological excavation in real time. The digital Sandby borg is a co- operation project between the Swedish exhibition agency, the south eastern museum archaeological unit at Kalmar County Museum, and Kulturmiljö Halland (Gunnarsson, et al.

2016:6-7).

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Fig 5 Drone photograph of the Sandby borg site. Photographer: Sebastian Jakobsson – Kalmar County Museum.

http://www.sandbyborg.se/bilder

3.6 The naval ship Mary Rose, Portsmouth, England

Mary Rose sank in the salty strait of the Solent, in the Atlantic sea, in 1545 (Stirland, 2013:2, 66-67), was rediscovered in 1971 and salvaged in 1982 (Bell, et al. 2009:167). The first plans to raise the Mary Rose was, however, formed in 1545, and resulted in a partial recovery of the ships rigging, sails, and yards, whereas the remainder of the ship was locked into the deep sediments at the seabed due to its rapid sinking and the sweeping tides of the Solent. Several attempts were made in the following years but none fully successful until 1982 (Stirland, 2013:6).

The wreckage of the Mary Rose was located approximately one kilometre of shore, and was due to the sweeping tides of the Solent, both covered and macerated by the silt that was swooped along with it (Stirland, 2013:66-67). The silt was of a fine grey character, and is one of the contributing factors for the good preservation conditions at the site (Stirland, 2013:71;

Conversation via email with Alex Hildred, 2017-05-29.).

The skeletal remains were lifted from the site immediately after the excavation and was sent to be put in rinsing baths, desalination. No human skeletal remains were left on the seabed (Conversation via email with Alex Hildred, 2017-05-29). The human skeletal remains located at the site had been placed in netting bags (Stirland, 2013:71), marked with a human bone number (Conversation via email with Alex Hildred, 2017-05-29), during the excavation and underwent a desalting process where the bones were placed in four different baths, each for one week, before being placed to dry (Stirland, 2013:71). The desalination process was highly prioritised (Conversation via email with Alex Hildred, 2017-05-29). Once dried they

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were numbered and sent to an osteologist for analysis (Stirland, 2013:71).

Fig 6 Documentation image of the Mary Rose wreckage after being salvaged from the seabed in 1982. Photographer: The Mary Rose Museum. Collected from http://www.maryrose.org/discover-our-collection/story-of-the-ship/image-galleries/ on may 15 2017. [Usage of the image in this thesis work has been approved by the Mary Rose Trust]

3.7 Previous research

Digital marine osteology is a new field and there is, therefore, a very limited amount of previous research to be listed. Information concerning the taphonomic processes affecting human and animal bodies and skeletal remains have mainly been compiled from forensic taphonomic literature due to the limited amount of research within the field of marine archaeology.

A digital osteological analysis was performed on the digitally documented skeletal remains of the naval ship Mars in the spring of 2015. The results of the analysis underlined that it was possible to collect osteological data through the use of image material as source material. Only four bone elements were distinct enough to be used for an osteological analysis. The bone elements consisted of a right human femur from an individual with the minimum age of 22, and showed possible trace of trauma in the knee region. The three other bone elements were determined to make up the right hip of a pig. The bone elements were determined to a femur, a tibia, and the right side of a pelvis (coxae). The pig femur showed signs of trauma probably related to the butchering process, and a discolouration possibly connected to absorption of foreign substances in the marine sediments or from exposure to

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fire (Fredriksson, 2015:16).

There is today a digitalisation project, referred to as the Digital Tudors project, between the Mary Rose museum and Swansea University, where photogrammatry is used in order to create 3D reconstructions of human skeletal remains in their collections. These 3D reconstructions are then sent out to different institutions for osteological analysis' of the digital reconstructions. The collected data is then sent back to the Digital Tudors project in order to be compiled and evaluated as an analysis method (http://www.maryrose.org/virtual- tudors-project/).

There has been very little research concerning the human and animal skeletal remains in marine contexts. The majority of research within this field has, however, focused on the taphonomic processes that affect skeletal remains at marine archaeological sites, but hardly any research has been done concerning the factors that affect the bodies before they are fully skeletonised. Some research has been done, but the researchers themselves stress the lack of previous research in the field (Sorg, et al. 2006:567; Anderson & Bell, 2016:2). It is, therefore, of great importance to underline the importance to problematise the taphonomic affects of human and animal bodies in marine archaeological environments. The majority of the research that has been performed has mainly been based on hard cases, for human remains, and experimental cases, for animal remains (Sorg, et al. 2006:567-568; Anderson &

Bell, 2016:2). This means that there is no cheat sheet for the taphonomic effects on human remains in marine contexts, and that the collected data is connected to accidents, homicides, or suicides. This also means that that very few experiments have been made on human remains in a controlled environments, similar to those performed on human remains placed in a terrestrial environments where the human decomposition process may be fully monitored, such as at the University of Tennessee’s Forensic Anthropology Centre (http://fac.utk.edu/) often referred to as the Body farm.

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4. MATERIAL

This chapter include the material descriptions of the analysed skeletal remains from the different sites. The chapter also introduce the compilation of taphonomic texts presented in Appendix 3. As the discussion is quite lengthy it has been separated as an appendix, but is introduced in this chapter and forms the basis of the taphonomic discussions presented in the discussion chapter (chapter 8).

4.1 The skeletal remains of the naval ship Mars

The skeletal remains documented at the naval ship Mars in 2015 consists of 220 images containing objects that could possibly be bone, as well as 7 confirmed bones. No possible bone elements or confirmed bone elements were documented in the 30 minutes of film material collected in 2015 (for further clarification concerning the possible bone elements see 2.1). For complete amount of image material, images containing possible bone elements and number of confirmed bones see table 1. For complete amount of film material, amount of possible bone elements, and number of confirmed bone elements see table 2.

Table 1 Compilation of image material; possible bones; confirmed bones, at the site of the naval ship Mars in 2014 and 2015 Field season Images Total amount of

images

Number images containing possible bones

Number of confirmed bones

2014 6 X 3

2015 10 942 220 7

Table 2 Compilation of film material; possible bones; confirmed bones, at the site of the naval ship Mars in 2014 and 2015 Field season Film Total hours Number films

containing possible bones

Number of confirmed bones

2014 18 3 1

2015 0,5 X X

4.2 The skeletal remains of the naval ship Gribshunden

The skeletal remains documented at the naval ship Gribshunden in 2016 consists of one possible bone element and one confirmed bone element (table 3 and table 4). Both elements were documented successfully according to the recommendations presented by the author to the divers. The noted possible bone element in table 3 is the same as the one noted as a possible bone element in table 4.

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Table 3 Compilation of image material of possible and confirmed skeletal remains at the naval ship Gribshunden at the field season of 2016.

Field season Pictures Total amount of Images Number of possible bones Number of confirmed bones

2016 852 1 1

Table 4 Compilation of film material of possible and confirmed skeletal remains at the naval ship Gribshunden at the field season of 2016.

Field season Film Total amount of film Number of possible bones Number of confirmed bones

2016 31 min 1 X

4.3 The skeletal remains at the Viking Age harbour of Birka

The skeletal remains collected in the Viking Age harbour of Birka in the field season of 2014 consisted of 16 289 grams of macerated dried bone element consisting of 10 593 fragments.

The osteological analysis was performed and compiled into an osteological report (See Fredrikson, In. Prep). For the complete amount of bone elements collected in the harbour see table 5. The analysis results from the 2014 osteological analysis are compiled in Appendix 1:

Bone lists, this due to the vast amount of information collected during the analysis.

Table 5 Compilation of the collection type, amount of bone elements, and weight of macerated bone elements retrieved at the Viking Age harbour of Birka.

Field season Bones Collection type Amount of bone elements Weight of macerated dried bone elements

2007 Core sample 304 3000 grams

2010 Excavated 864 x

2012 Excavated 87 5335 grams

2014 Excavated 10 593 16 289 grams

4.4 The skeletal remains of Çatalhöyük, Anatolia, Turkey -3D

The 3D reconstructed skeletal remains of Çatalhöyük consist of human skeletal remains placed in grave 40. The individual was placed in a foetal position on its back.

The 3D reconstructions at Çatalhöyük were created in order to illustrate the conditions at the site and are in this thesis work used in order to illustrate and discuss the possibilities and limitations of 3D reconstructions as source data for an osteological analysis. This in order to underline and discuss the general possibilities and limitations of analysing digitally documented skeletal remains in a terrestrial context to further discuss the possibilities of applying the same work method in a marine context.

The human skeletal remains of grave 40 was analysed with the permission of PhD Scott Haddow and Professor Ian Hodder at Stanford University, USA.

4.5 The skeletal remains of Sandby borg, Öland, Sweden - 3D

The skeletal remains of Sandby borg used in this thesis consists of two individuals located at the excavations in 2015. Both individuals were found within house 40 together with six other individuals. All eight individuals had been killed at the site, and neither had been buried.

The 3D reconstructions were created in order to illustrate the conditions at the site and

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are in this thesis work used in order to illustrate and discuss the possibilities and limitations of 3D reconstructions as source data for an osteological analysis. This in order to underline and discuss the general possibilities and limitations of analysing digitally documented skeletal remains in a terrestrial context to further discuss the possibilities of applying the same work method in a marine context.

The human skeletal remains of Sandby borg were analyzed with the permission of Fredrik Gunnarsson at Kalmar County Museum, Sweden.

4.6 The skeletal remains of the naval ship Mary Rose, England

The documented bone elements consist of a selection of human skeletal remains stored at the Mary Rose Museum. The documented bone elements range from well preserved with limited amount of taphonomic alterations to well preserved and highly taphonomically affected. The collected image material has been sent to the Mary Rose Museum for approval for usage in this thesis work, and stored for future reference connected to the skeletal remains of the analysed individuals. The image material consists of 276 images connected to the individuals and 20 bone elements listed in table 6. Some images have been included in this thesis in order to illustrate the representation of noted taphonomic effects of the skeletal remains of the crew of the Mary Rose. The selected image material includes taphonomic alterations such as salt staining, metal absorption, mineral absorption, and general staining. The selected image material also include image material of well preserved skeletal remains, this in order to underline the contrast between the highly altered bone elements in contrast to the bone elements with very little to none alterations.

It is also important to underline that the bone elements were retrieved in a marine context where the sediments consisted of grey silt (Email conversation with Alex Hildred, 2017-05-29).

Table 6 The skeletal remains of the crew of the Mary Rose. Compilation of the collected data of taphonomic changes noted for the individual bone elements, as well as information noted during the documentation process.

Additional information

Individual #75 LH Archer.

Cranium Images 443-467

Taphonomy Discolouration, metal absorption

Pathology & Trauma Trauma temporal/occipital.

Swimmers ear - Otitis externa

Scapula ² Images 693-719

Taphonomy Metal absorption

Individual #84

Humerus ² Images 470-481

Scapula ² Images 482-486

Coxae SIN Images 487-491

Coxae DEX Images 492-500

Ulna ² (discolouration DEX) Images 501-520

Radius SIN Images 521-530

Radius DEX Images 531-542

Femur DEX Images 543-559

Femur SIN Images 560-574

Tibia SIN Images 575-603

Tibia DEX Images 604-615

Taphonomy Slight staining. Some traces of salt absorption Individual #14

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Femur SIN Images 616-628

Coxae DEX Images 629-667

Coxae SIN Images 668-692

Taphonomy Metal and clay mineral absorption

4.7 The osteology students exercise

The osteology students exercise was based on ten animal bone elements hand-picked from the practice material available at the osteological laboratory at Uppsala University Campus Gotland. The ten bone elements were documented individually and were placed next to a measuring stick for size reference. The image material was compiled into a work sheet together with the work instructions needed in order to fulfil the task. Each bone element were then given an individual number and placed in an archaeological find box. Each bone number correlated to the collected image material of each bone element (Appendix 2: The osteology student exercise).

The osteology students exercise was performed in two stages where the students at the first stage performed an osteological analysis of the image material presented to them in the work sheet, through the use of the osteological reference collection and literature available in the osteological reference collection at Uppsala University Campus Gotland. The students were handed the physical bone elements during the second stage in order to perform a physical osteological analysis of the same bone elements that had previously been analysed based on an image material.

The students were allowed to sit in any of the two areas of the osteological laboratory at Uppsala University Campus Gotland. The two areas are here referred to as region A and B.

The work sheets were to be collected in a pile at one of the assigned desks in each room, and numbered in the order they were collected, but one work sheet was left at one of the work desks in region B and was, therefore, collected and numbered in a different way than intended. For complete osteological results see Appendix 2: The osteology student exercise:

compilation.

4.8 Human and animal remains in marine environments

One of the main focuses in this master's thesis is the combination of osteology and forensic science. It is of great importance for osteologists to understand, not only the cause of death of an individual, but how the taphonomic effects of the surrounding environment affect both the process of decomposition, distribution patterns, and the preservation conditions of skeletal remains. Taphonomy is the main key when working with skeletal remains that have been submerged in water for centuries, and is a field that conjoins the forensic sciences with osteoarchaeology in a way where the two fields may learn a lot from each other through combining their experiences and intellectual resources.

In order to understand skeletal remains it is, therefore, important to have a greater understanding of what happens at the event of death, during the process of decomposition, and how different environments affect both bodies and bone tissue. It is, therefore, important to form an understanding of general taphonomy during the initial stages after death before striving to understand the taphonomic effects of bodies and bones in marine environments.

These factors are, therefore, presented in Appendix 3, and are used for the basis of the discussion concerning bodies and bones in water (Appendix 3: General taphonomy, and bodies and bones in water).

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5. THEORY

Osteological analysis' of skeletal remains found in marine archaeological contexts is nothing new, but the approach where digital documentation of skeletal remains left in-situ may be used as a source material for osteological analysis has not previously been tested by others than the author of this thesis. It is, therefore, not possible to position the work in this thesis directly to similar research. It is, however, important to underline that this thesis approach the results collected through the different forms of source material through applying a methodological uniformitarianistic perspective. This based on the idea that what is true today was also true in the past, and that we may only explain the world through the laws of nature as they are dictated by scientists at this point in time (Lyman, 2005:47-48). Through the use of this approach it is possible to discuss how different internal and external taphonomic processes may have affected bodies and skeletal remains in marine archaeological contexts through the use of forensic literature based on modern cases and experiments. Through this perspective it is also possible to apply the debate concerning the perception differences between visual and tactile sensation, where it is highlighted that some materials may appear different in an image than it would in real life (Chen & Chuang, 2014).

The two main objectives in this thesis concern which information is available to the osteologist through the different forms of source material, and in extension how the skeletal remains should be documented in order to increase the amount of osteological information available to the osteologist. The second objective is to highlight how bodies and skeletal remains are affected by the marine environment, and in extension how these factors may explain the limited amount of skeletal remains located at the marine archaeological sites of the naval ships Mars and Gribshunden.

The taphonomic processes related to bodies and skeletal remains in marine environments were compiled and used as a basis for the discussion in order to attempt to both present a general description of how bodies and skeletal remains are affected by the marine environment, as well as in an attempt to discuss how these factors may have affected the skeletal remains at the marine archaeological sites of the naval ships Mars and Gribshunden.

In order to further discuss the taphonomic processes that directly affect the bone tissue, an observational study was performed on the physical skeletal remains of the men of the naval ship Mary Rose, and the animal skeletal remains of the Viking Age harbour of Birka.

In this thesis the skeletal remains are analysed based on the information that may be retrieved from the three different source materials (physical, 2D, 3D), and is used in order to highlight the information available to the osteologist through the three formats. The analysis results may then be compared to each other in order to form a basis for a discussion concerning how skeletal remains preferably should be documented in-situ in order to retrieve as much information as possible during an osteological analysis.

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6. METHOD

The theoretical part of this thesis is based on literature including previous research of human and animal remains in marine environments. The literature was here used in order to present how bodies, body parts, and bone elements can be affected by the marine environment both when it comes to fluvial transport, disintegration, and discolouration. This in order to discuss how the located skeletal remains have been affected by the environment, and why only a small amount of skeletal remains have been located at the sites of the naval ships Mars and Gribshunden.

The practical part of this thesis is based on the observations made on three different formats of skeletal remains: physical; 2D documentation (photographs and film); 3D reconstructions (a three dimensional picture where the viewer may see an object from several different angles through rotating and turning the reconstructed object). The osteological analysis was performed according to the methods listed under heading 6.1. The documentation and collection of data through digital documentation, may also be described through the use of the term remote sensing, where information is collected through non- invasive methods in-situ through either direct ocular observations or photographic documentation (Haralick, 1976:5).

6.1 Osteological analysis

The osteological analysis was performed based on morphological characters of the digitally documented skeletal remains, this due to the lack of possibility to measure the different bone elements. The osteological reference collection at Uppsala University Campus Gotland was used for bone element assessment and species identification during the analysis of the digitally documented skeletal remains of the naval ships Mars and Gribshunden.

6.1.1 Identification of species

Identification of species was performed through the use of the Uppsala University Campus Gotland reference collection, the Swedish History Museum reference collection and the books: Comparative Osteology (Adams & Crabtree, 2012); Anatomie comparée des mammifères domestiques (Barone, 1976); Atlas of animal bones (Schmidt, 1972); Human and Nonhuman bone identification (France, 2009); Birds (Serjeantson, 2009); Fishes (Wheeler &

Jones, 2009).

6.1.2 Bone element assessment

Identification of bone elements was performed through the use of the Uppsala University Campus Gotland reference collection, the Swedish History Museum reference collection and the books: Comparative Osteology (Adams & Crabtree, 2012); Anatomie comparée des mammifères domestiques (Barone, 1976); Atlas of animal bones (Schmidt, 1972); Human and Nonhuman bone identification (France, 2009), Birds (Serjeantson, 2009), Fishes (Wheeler &

Jones, 2009).

6.1.3 Age assessment

Age assessments for domestic animals are based on epiphyseal closure according to Silver

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(1969) and tooth wear according to Grant (1982).

Age assessment for humans are based on epiphyseal closure according to Buikstra &

Uberlaker (1994).

Epiphyseal closure occurs at different stages in an individual's life and can, therefore, be used to estimate an approximate age.

6.1.4 Withers height

Withers height calculations for domestic animals are based on the greatest length of the talus bones of pigs and sheep according to Teichert (1969).

6.1.5 MNI assessment

For this Master's thesis the simple MNI (Minimum Number of Individuals) count based on Gautier (1984) was used in order to estimate the minimum number of individuals documented on the sites of Mars, Gribshunden, and Birka. This through sorting the bone elements into species, bone elements, estimated ages, and then comparing the results to the amount of singular or plural bone element representation for a singular individual.

6.2 Literature review

As discussed above. In an attempt to answer the theoretical work questions of this thesis a thematic literature review has been performed. This means that information has been retrieved and compiled (see Appendix 3: General taphonomy, and bodies and bones in water) through the use of literature and video documentation concerning: the fluvial transport of bodies, body parts and bones, the disintegration of human and animal bodies in marine environments (Haglund & Sorg, 2002; Phillipe & Modell, 2005; Nawrocki, et al. 2006; Boyle, et al. 2006;.

O´Brien, 2006; Sorg, et al. 2006; Brooks & Brooks, 2006; Lange, 2006; Magnell, 2008;

Evans, 2014; Video¹, 2015; Video², 2015; Andersson & Bell, 2016), taphonomy and the absorption of foreign substances in bone tissue (Haglund & Sorg, 2002; Nawrocki, et al.

2006; Higgs & Pokines, 2014; Dupraz and Schultz, 2014) and any additional information these aspects may provide during the osteological analysis.

6.3 The osteology student exercise

The osteology student exercise was performed in the spring term of 2016 by eight osteology bachelor students at Uppsala University Campus Gotland, where the students performed osteological analyses on ten different bone elements in both physical and 2D format.

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7. RESULTS

This chapter will begin with presenting the osteological analysis results, and then proceed to present the factors affecting human and animal bodies and bones in marine environments.

The osteological analysis results

The analysis results differ between the physical, the 2D, and the 3D osteological analysis' for several different reasons. One of the main reasons is that the amount of bone elements represented in each format differs greatly from 10 593 bone fragments at the Viking Age harbour of Birka, to one bone element at the wreckage site of the naval ship Gribshunden.

What is, however, important to underline is the type of information that could be retrieved through the use of different forms of osteological source material. One of the factors to take into consideration is the representation of bone elements, some bone elements contain more information about the individual than other bone elements and may be easier to separate from other species than other bone elements. The represented bone element is, therefore, key in the collection of osteological data, and the more bone elements that are documented, the more likely is it that there will exist some bone elements that are more likely to be identified and used for the purpose of age assessment, sexing, or calculations of withers height etc.

During the osteological analysis of the animal skeletal remains in the Viking Age harbour of Birka, it stood clear that it was possible to retrieve information such as species, age, withers height, age, side, trauma, and taphonomic changes to the bone tissue. During the osteological analysis of the 2D format digital documentation (the naval ships Mars and Gribshunden) it stood clear that it was possible to retrieve information such as species, bone element, possible trauma, bone elements greatest length, and taphonomic changes to the bone tissue. During the osteological analysis of the 3D reconstructed skeletal remains (Çatalhöyük

& Sandby borg) it stood clear that it was possible to retrieve information such as species, bone element, age, sex, trauma, and taphonomic changes to the bone tissue.

The Viking Age harbour of Birka

Due to the large amount of bone elements analysed during the osteological analysis of the animal skeletal remains at the Viking Age harbour of Birka, the results will here be compiled into a short summary in order to highlight the information available to the osteologist during the analysis.

The bone element fragments that could be determined to a specific species during the osteological analysis was: Cattle, horse, pig/boar, elk, sheep, goat, badger, fox, dog, fish, and bird. Several bone elements could only be determined as mammal, ungulates, sheep/goat, bovines, cervid, elk/deer (table 7). For species representation in the different cultural layers see Fredriksson (in. prep).

Thirteen age assessments could be performed on cattle, based on Silver (1969), where ten of the individuals were younger than four at the time of death. Four of the cows were younger than one and a half year at the time of death. One of the cows were at least one year old, and only one of the cows were older than two and a half years at the time of death (table 8). Two age assessments could be performed on sheep, based on Silver (1969), where one of

Digital Marine Osteoarchaeology: The problematization of bodies and bones in water