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The Wonders of Easter Island: A BBC Documentary

2 Feb

I have been pleasantly surprised by the great many documentaries aired on the BBC Four channel that focus on archaeology, perhaps none more so than a recent series entitled Lost Kingdoms of South America.  Presented by the knowledgeable and engaging Dr Jago Cooper, the series explored various (and to me some unknown) cultures in the pre-Colombian continent.  I admit to having a great interest in Mesoamerican and South American archaeology, as such it was a delight to watch these detailed documentaries.

Therefore I was quite happy to come across another BBC 4 feature the other day, this time with a focus on Easter Island (here-after Rapa Nui), a tiny Pacific volcanic island well-known for the megalithic human moai statues that dominate the landscape and the birdman cult that super-ceded the creation of the statues (Lipo et al 2013).  For a previous undergraduate essay I had researched the island’s history so I was familiar with the ecocide theory, the tale of the island’s supposed descent into war/ruin after using up the majority of the island’s natural resources.  However this documentary discovered a far more nuanced tale to tell.

easterislandmap

Geographic location of Easter Island, one of the most isolated inhabited islands in the world. Annexed by Chile in 1888, the island remains a special territory of the country. The aboriginal habitation of the island from Polynesian populations is hypothesized to have been in the mid 1st millennium AD (700-1100), although dates vary widely (Chapman 1997). The pre-European contact population maximum is thought to have been around 14,000 individuals, although post 1722 (the year Roggeveen landed) the aboriginal population greatly diminished and fluctuated due, in part, to slavery exploitation, the introduction of new diseases and repeated famines. The modern population currently stands at around 5800. (Image credit: Eric Gaba 2008).

Once again presented by Dr Jago Cooper, an archaeologist and curator at the British Museum, the 90 minute documentary was an interesting and informative show.  It was a pretty comprehensive overview of the history of the people of Rapa Nui, discussing their somewhat still mysterious origins (Chapman 1997) right through to the issues that dominate the island to this day.  It was also a show that actively engaged with a wide range of current specialists on the history and archaeology of the island.  It detailed not just the controversial theories of the island’s ecological diversity decline, but also the range and depth of archaeological research conducted on an island that has captivated and captured the hearts of many.

I am not going to review the whole program here but I do want to highlight a few parts where, for me, the program really came alive with the great value that archaeology has to offer.

Ecology and Landscape at Rapa Nui

The ecology and landscape environment of Rapa Nui have undergone extensive changes throughout the human habitation of the island, perhaps none more so than in the last 400 years.  Visitors to the island today will note the largely steppe like appearance of the landscape – the only trees still standing can largely be found around the main settlement of Hanga Roa in the south-west of the island.  The island was previously heavily forested with trees, shrubs and ferns.  The main predominate tree of the forested island was the now extinct palm tree Paschalococos disperta (Rapa Nui palm), which disappeared from the environmental record around 1650.  It is important to note that while there are various extinction events of various flora and fauna (land-birds such as herons and parrots) throughout the island’s natural history, there seems to be a fairly major change in landscape and ecology in the middle of  the 2nd millennium AD (Chapman 1997).

Although there are many theories on the collapse of the ecology of the island (from over-population, the various causes of intense deforestation and the impact of invasive species) it is likely thought that a combination of these and other factors were involved.  It is not my intent here to discuss this but to highlight the implications of this in the archaeological record.

The loss of the forests that covered Rapa Nui has led to some serious consequences in the landscapes ability to hold minerals and water in the soil.  The Roggeveen expedition of 1722, at least a century after the extinction of the main palm trees, stated that Rapa Nui was exceptionally fertile in its soil quality, that the population successfully cultivated sweet potatoes, bananas and sugar cane.  Further expeditions in the 18th century repeated claims of fairly well fed individuals.  This is interesting as we have archaeological and palaeoenvironmental evidence of a decrease in the ecological flora typically ascribed to a sub-tropical Polynesian environment.

The program shed light on this topic in a few surprising ways.  Firstly there are numerous caverns throughout Rapa Nui, some of which have carved artwork and glyphs attributed to different tribal groups.  Some, however, were clearly used as agricultural areas to help grow banana crops and sweet potatoes.  Further to this there was also evidence of lithic mulch across the island, that at least some of the forest chopped down was to make way for agricultural plots of land.  This, for me, was a new term I had not come across before.  It is the laying stones (of varying sizes, but in this case just under football size) across the landscape in small plots of lithic mulch gardens or in larger areas to encourage more nutrients into the soils and stabilize the landscape.

easterisnaldrocks

Dr Jago Cooper, some rocks and a horse.  The process of using lithic-mulch to help grow food produce has been used in countries throughout the world, and it is a distinct process though one that can be overlooked. (Image credit: BBC).

This encourages the retention of minerals and water in the soil below encouraging plant growth and helps to increase  the crop biomass and overall yields.  The stones also help to decrease/stop the rate of soil erosion from wind or water run off and shadow the soils from direct sunlight whilst also producing an environment which encourages other vegetation to grow (Lightfoot & Eddy 1994: 425).  Lithic mulch gardens have been noted at a variety of archaeological sites across the world that occur in predominately dry environments (Anasazi and Hohokam sites in Arizona, Negev in Israel, Maori in New Zealand etc) (Lightfoot & Eddy 1994: 426).

Inevitably the ecology and landscape has changed due to the actions of the human populations, both from those that are aboriginal and those that visited the island post-European contact.  Perhaps most damaging to the island soil ecology was the widespread grazing of over 70,000 sheep in the early 20th century, helping to destabilize the soils which has led to intense soil and field erosion ever since.

 The Moai and the Ahu Platforms

The moai are the quite wonderful sculpted megalithic stone statues, made mostly of volcanic tuff, that dominate the island.  They are largely found on either ahu platforms in groups or dotted around inland individually (termed road statues).  They are largely quarried from the main site of Rano Raraku on the foothills of the Terevaka volcano, the highest point on the island.  Around 887 statues have been documented and recorded so far, with almost 50% of them still located in and around Rano Raraku in a variety of completed states (Lipo et al 2013).  The statues were created over a 500-600 year period in the early part of the 2nd millennium AD, although exact dates are not known.

The smoothed statues are known for their overly large heads and minimal stylistic appearance that are carved in flat planes.  With an average height of 4 meters and width of 1.6 meters, the statues weigh in at 12 tonnes on average, although there are exceptions and some are often rather larger and heavier.  Some statues also have pukao, either hats or hairstyles, that adorn the top of the statue heads, which can weigh many tons themselves.  Although nearly every statue recorded is in a standing pose there is one statue that shows a kneeling position, Tukuturi at Rano Raraku, that also has a beard – a highly unusual feature of the statues and reminiscent of other Polynesian societies.  It is thought that this individual was carved late in the statue phase.          

easterislandahu

The Rapa Nui moai, with one of the individuals ‘wearing’ a pukao. Note the ahu stone platform on which the statues are standing on, and the fairly desolate landscape behind the statues. There is evidence to believe that the statues, or at least some of them, had been painted over in a variety of colours with coral and stone insets for eyes.  During the Birdman cult era glyphs were also added to some of the statues (Image credit: BBC).

A number of the statues are found on the ahu fitted stone ceremonial platforms that can be found around the whole perimeter of the island.  Nearly every ahu platform faces inland – there is only one documented case where the statues face out towards the sea.  It is thought that the statues represent the chiefs of ancestors of the aboriginal population, with the individuals facing inland towards their respective tribal land (Lipo et al 2013).  Researchers have also noted the boundary motifs of tribes on some moai throughout the Rapa Nui island, suggesting that fairly individual identities existed (Chapman 1997), regardless of their ancestral origin (Stefan 1999).  The ahu platforms consist of carefully fitted stone sections with distinct stone wings to the side of the platform and stone fields out to the front of the platform.

The documentary highlighted the fact that it is likely a variety of methods were used to transport the statues to their respective sites. There was a pretty impressive part where it was highlighted that the statues could walk to site:

easterislandwalking

Noted in the oral tradition of the native Rapa Nui population, the walking of the statues to their site could have been possible as Lipo et al. (2013) demonstrated with their smaller size replica statue in some rather interesting experimental archaeology. Wooden rollers and other methods of transportation have also been discussed. (Image credit: BBC).

Lipo et al. (2013) have stated that wear marks on the torso and heads of the statues indicate that great pressures were hinged at these areas suggesting that the size, shape and centre of gravity of the statues all point towards a rocking motion to gather the momentum to walk the statues.

After the initial contact with European sailors following Roggeveen’s landing in 1722 (in which the moai were still standing) it was reported that the toppling of the statues had commenced, with almost no statues standing on the ahu platforms by 1868.  It has been postulated by some researchers and historians (Lipo et al. 2013) that the statues were thrown down with force by rival tribal bands, but others have pointed out that at least some of the statues were carefully placed face down.  What is known is that some of the ahu platforms where the statues are face-down also function as ossuaries or burial complexes.  Today a total of 50 moai have been placed back in the standing position, whilst a few have been shipped to institutions are the world (Lipo et al. 2013).

For further information on the Moai I’d recommend checking out an ongoing project entitled Easter Island Statue Project, co-directed by Jo Anne Van Tilburg and Cristián Arévalo Pakarati, whose homepage can be found here.  A detailed map of the moai on the ahu platforms on the island can be found here.

Human Osteology and Population Origin

I think it is pertinent to touch on here a few of the (few) human osteology studies that have been carried out on aboriginal skeletal material of the Rapa Nui.  It has long been argued by some early archaeologist, such as Thor Heyerdahl, that Rapi Nui and other Polynesian islands were settled by Native Americans.  Although some archaeologists concede that contact between Native Americans and Polynesians was feasible (Chapman 1997: 161), the majority of the osteological and genetic tests carried out on human skeletal material indicates a Polynesian origin for the aboriginal inhabitants of Rapa Nui (Chapman 1997, Chapman & Gill 1998, Stefan 1999).

Chapman & Gill (1998: 189) measured the stature of 92 individuals from the Rapa Nui aboriginal population (54 males and 38 females from prehistoric (A.D. 1680-1722) and protohistoric (A.D. 1722-1868) populations.  The individuals were taken from the various tribal populations on the island and the bones (in ranked order: femur, tibia, fibula, humerus, radius or ulna) were measured and analysed using a regression formula devised for New Zealand Maori populations (Chapman & Gill 1998: 189).  The results stated that there was no statistical difference between the tribal areas of the island and stature, male average was 1726 mm and 1595 mm for females, reflective of general sex dimorphism (Chapman & Gill 1998: 191).  The stature range was found to be within range of other Polynesian groups and there were no obvious differences in stature within the population of the Rapa Nui island.

OLYMPUS DIGITAL CAMERA

Measuring a right humerus with an osteometric board and a calculator. Stature estimation is a vital technique in bioanthropology to gauge the height of past populations (useful guide here, image credit: Paul Duffy at Aberdeen Council).

Stefan (1999) and Chapman’s (1997) studies both indicate that the initial aboriginal population of Rapa Nui were from Polynesian origins.  Stefan’s (1999) studied 50 cranio-facial measurements on the crania of  prehistoric/protohistoric Rapa Nui populations and discovered greater between-group homogeneity in males than females but not the population as a whole.  Chapman (1997: 171) study does highlight the need to thoroughly investigate the prehistoric and protohistoric populations genetically for any further population admixture and genetic drift from later populations, with the need to specifically sample individuals from each main geographic location of the island.  As far as I am aware I do not know of any stable isotopic work that has been carried out on the skeletal remains, but this could add another informative dimension to understanding the Rapa Nui culture (1).

It must also be remembered  the island was repeatedly visited (and raided) after Roggeveen’s first landing by European ships in the same century, which ultimately led to a rejection of all ships by the Rapa Nui.  During the 19th century Peruvian ships also repeatedly and successfully made slave raids on the island, capturing up to a thousand aboriginals to work in the mines in Peru.  The slave raids, but also the introduction of new diseases from the Europeans and from surviving miners, caused the aboriginal population to dramatically fall resulting in an aboriginal population of only 111 individuals at one point in 1877.  Although a historic low, the population had undergone fluctuation before but probably never to this dramatic extent.  The documentary state that around half of the modern population (around 2500 individuals) claim to be genetically related to the original aboriginal population.

The program also produced a succinct point by highlighting the ongoing struggles of Rapa Nui to become recognised as an independent island.  There are still many controversies surrounding the Rapa Nui culture and as highlighted above there is still little agreement on certain key points of the population history of the island and the ecological effects that this produced.

Conclusion

Although only briefly mentioned here it is worth noting that Rapa Nui has evidence for a rich and diverse culture.  Interestingly Forment et al. (2001) highlight the fact that the wooden carvings of human figures, known as moai kavakava, were being carved and produced in the same period as the terminal phase of the megalithic statues.  Also noted is the fact that the wooden carvings probably do not indicate accurate physical reflections of the population (Forment et al. 2001: 532) as some researchers have suggested.  There are also numerous petroglyphs present throughout the island as well as an apparent script called rongorongo, which included glyphs of geometric and pictographic images (Chapman 1997).  Although Rapa Nui is only 15 miles by 7 miles in size, it has produced an incredibly diverse cultural legacy and material culture.  This is echoed today by the living population who understand the very real threat of population collapse and remain intent to keep their culture, and cultural heritage, alive.

Notes

(1). If I am mistaken (I only did a quick literature search) please email me or drop a comment below.

Important Update 25/10/14

New genomic evidence has shown that the human population of Rapa Nui had contact with the Native American populations from around AD 1300-1500.  The genome wide study of 27 native Rapa Nui individuals has discovered that there was significant contact between the inhabitants of Rapa Nui and Native American populations from around 19 to 23 generations ago.  The evidence for European based population admixture dates from around AD 1850-1895.  This is an outstanding piece of news, please see the Past Horizons article for more information.  The 2014 Current Biology article can be found here.

Further Information

Bibliography

Chapman, P. M. 1997. A Biological Review of the Prehistoric Rapanui. The Journal of the Polynesian Society. 106 (2): 161-174. (Open access). 

Chapman, P. M. & Gill, W. G. 1998. Estimation of Stature for the Prehistoric/Protohistoric Rapanui. The Journal of the Polynesian Society. 107 (2): 187-194. (Open access).

Forment, F., Huyge, D. & Valladas, H. 2001. AMS 14C Age Determinations of Rapanui (Easter Island) Wood Sculpture: Moai Kavakava ET 48.63 from Brussels. Antiquity. 75: 529-32. (Open access via academia).

Lightfoot, D.R. & Eddy, F.W. 1994. The Agricultural Utility of Lithic-Mulch Gardens: Past and PresentGeoJournal. 34 (4): 425-437. (Partially open access).

Lipo, C. P., Hunt, T. L. & Haoa, S. R. 2013. The ‘Walking’ Megalithic Statues (Moai) of Easter IslandJournal of Archaeological Science40 (6): 2859-2866. (Abstract only).

Stefan, V. H. 1999. Craniometric Variation and Homogeneity in Prehistoric/Protohistoric Rapa Nui (Easter Island) Regional Populations. American Journal of Physical Anthropology. 110 (4): 407-419. (Abstract only).

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Killer Whales: A BBC Natural World Documentary

26 Oct

The BBC strand of a wildlife documentary series, entitled Natural World, have a new episode up on the BBC Iplayer focusing on recent scientific research on the globally distributed killer whale (Orcinus orca).  It is available to view here, although readers outside of the UK may have trouble watching it online (If you have any links please leave a comment!).

It was whilst watching the program, and its discussion on whether there are different species of killer whale (likely 3-5, with various sub-species), that it reminded of the Dmanisi Homo erectus fossils (Lordkipanidze et al. 2013) which were subject of the previous post.  Lordkipanidze et al. (2013: 330) postulated that the morphology of the 5 Homo erectus crania present at Dmanisi, Georgia, represent, when examined against comparable material, the evidence for wide morphological differences within and among early Homo, possibly indicating rather less individual species than is currently documented and described.

The Natural World episode highlighted the differences between killer whale ‘cultural’ groups and species with niché but distinct differences in external anatomy (body size, eye and saddle markings, shape and size of dorsal fins), vocalisation and the different hunting methods used when groups targeted varying prey groups.  This is important as it will help to inform on how humans try to conserve killer whale populations around the globe as an understanding of the distinct species could have an important ecological impact on what groups of killer whales are under threat the most.  Of course the big difference between the above comparison was the use of DNA testing and active observational fieldwork, if only we could test the early Homo fossils in such a way!

Further into the program we came across evidence of an individual killer whale who had likely been maimed as a juvenile and who had been adopted, at different times, by no less than 4 different pods of killer whales. There was also footage of said killer whale shadowing and receiving food from one member of her current pod who could successfully hunt (whether this was deliberate is another question).  This reminded me of a nice little paper by Fashing & Nguyen (2011) of the relevance of behaviour towards disabled, injured or dying individuals among animal groups and it’s relevance towards palaeopathology.

Palaeoanthropologists should take into account the wider aspect of how animals treat members of their own species when they are disabled, injured or dying, as Fashing & Nguyen (2011: 129) note that ‘recent evidence from paleoanthropology indicates that inferences into the evolution of human behavior based solely on a chimpanzee model are less informative than previously believed’.  Lordkipanidze et al. (2013), in their study, compare the Dmanisi individuals against modern Homo sapiens and chimpanzees, amongst others, but it could be said that these two groups in particular do not reflect good study comparative groups as their anatomical plasticity is generally quite homogeneous.  As ever, of course, further research is needed and I for one look forward to it.

The program also debated the troubling nature of the capture of killer whales for the purposes of entertainment for large sea life centers across the world, a practice that has now been largely banned in the Western World.  There is a haunting passage in the Natural World episode showing archive footage of the frenzy of killer whale captures during the 60’s and 70’s, with an appropriately sinister (and awesome) Pink Floyd track playing in the background.  Killer whales are, by their nature, large social predators – they need the security of their family pods and the sea environment in which to live and to hunt.

At SeaWorld, in the United States of America, there have been a recorded 100 separate episodes of aggression towards humans from captive killer whales since 1988, and there have been 4 recorded fatalities of trainers involving captive killer whales across the globe.  Let me re-iterate here that killer whales pose little threat to humans in the wild, that there has been no recorded human death by killer whale in the wild but there have been incidents (see list).  Clearly captivity leads to abnormal behaviour amongst these amazing creatures, as it can be said for many animal species (worth a watch is the 2013 documentary Blackfish).

All in all, this was an enlightening program on the advances made in studying the killer whale, highlighting the distinct hunting differences, group structure and vocalisation of an apex predator who has both inspired and caused fear in humanity throughout the ages.  It is well worth watching the episode, if not the series, for insights into the natural world.  Previous episodes worth a watch also deal with the remarkable walrus and the delightful orangutan.

Watch the BBC documentary here (United Kingdom residents only).

Bibliography

Fashing, P. J. & Nguyen. 2011. Behavior Towards the Dying, Diseased, or Disabled Among Animals and its Relevance to Paleopathology. International Journal of Paleopathology. 1 (2-3): 128-129.

Lordkipanidze, D., Ponce de León, M. S., Margvelashvili, A., Rak, Y., Rightmire, G. P., Vekua, A. and Zollikofer, C. P. E. 2013. A Complete Skull from Dmanisi, Georgia, and the Evolutionary Biology of Early HomoScience.  342 (6156): 326-331. (Full article here, email if this doesn’t work).

Dental Delights and Disability in Archaeology

26 Mar

I’ve recently had the joy of a dealing with a dental abscess affecting the left hand side of my mandible, and whilst I’m thankful for modern medicine I can only imagine the pain and frustration for pre-modern populations suffering with such an infection, especially those who didn’t have access to antibiotics and strong painkillers.  As such I haven’t posted properly for a while, and it might be a bit longer before I do.  Having had surgery to relieve the effect of the swelling and to drain the infection and remove two pesky teeth (with added complications courtesy of Fibrous Dysplasia), I’m once again learning how to chew (farewell 1st and 3rd left mandibular molars!).  It has also given me the time to think about the role of disability in the archaeological record and how it is approached by modern-day researchers.  What follows below is a very quick and brief overview of the main points of how disability has been approached in the archaeological sector and the changes therein.  Articles of interest are noted in the bibliography.

Dettwyler famously wrote a paper entitled ‘Can paleopathology provide evidence for compassion‘ (1991: 375-384, PDF embedded) that rightly questioned the interpretations of archaeologists and osteologists on the inferred aspects of care and compassion that disabled individuals from the archaeological record may or may not have received during their lifetimes.  The author cautioned that archaeologists and researchers are not ‘justified in drawing conclusions either about quality of life for disabled individuals in the past or attitudes of the rest of the community from skeletal impairment of physical impairment’ (Dettwyler 1991: 375).  This was a much-needed wake up call, and rightly raised questions in the realms of archaeology and palaopathology regarding how we viewed individuals, and how we analysed them.

The majority of disability studies before the Dettwyler (1991) article focused on disabled individuals as case studies, reported in journals and rarely integrated or investigated as part of the society or cemetery population they may belonged to.  Mays (2012) rightly investigated the impact of the relative value of individual case studies compared to quantitative and problem orientated population studies, and found that although the publishing gap had lessened between the two types, singular case studies still predominated.  Mays (2012) main contention is that individual case studies do little to further the advance of palaeopathology, something which Larsen (1997) effectively demonstrates throughout his book and review (2002), in the consideration of how palaeopathology can indicate society or cultural wide rituals, actions or lifestyles.

Since the publication of the Dettwyler paper there has been a slew of articles, journals and books dedicated to researching disability as evidenced from the skeletal and archaeological record, both from a bioarchaeological perspective and from a theory perspective (Battles 2011, Brothwell 2010, Hawkey 1998, Kleinman 1972, Vilos 2011, Wood et al. 1992).  Indeed the study of disability and the implications for affected individuals, their communities and societies, has moved on considerably since the descriptive days of Calvin Wells, especially in the consideration of the theory of ‘compassion’ as an evolutionary force in the primate family (Hublin 2009, Stewart et al. 2012), or as evidenced in other mammals (Fashing & Nyuyen 2011).

This is in accordance with the rise and debate of disability theory and studies in numerous other disciplines.  This has had real life applications in many areas of modern-day life, where multi-agented approaches to understanding,  recognising and implementing programs that are designed to raise awareness or life quality for disabled individuals.  Two prominent examples from the UK are the 2005 Disability Discrimination Act and the 2010 Equality Law where disability itself is given a legal definition, and here we come to a prominent problem in the archaeological and palaeopathological record itself.

Disability, as we would recognise it today, can mean both a physical and/or a mental impairment that can be substantial and lifelong, and it is worth noting some problems inherent in the archaeological record.  Firstly, in the archaeological record, we can only recognise physical disability when it has affected the skeletal remains of individuals, normally at a late and severe stage in the disease progression (Aufderheide & Rodriquez 1998, Waldron 2009, Wood et al. 1992).  As such, a large number of individuals with diseases or traumatic injuries that only affected the flesh will go unknown, and as such are unstudied.  Secondly, there is no universal or standard definition of disability that archaeologists and researchers use, it is solely up to the person/persons to define clearly and openly which definition they are using at the outset of their research (and there are a lot of definitions and models depending on which source you base your definition on).  Thirdly, the usage of terminology itself, such as the very word disability, can have vastly different connotations or implications for different populations and cultures (Battles 2011).

There may have been distinct differences as to who was considered disabled or not in historic and prehistoric cultures, and we should, as researchers, always be aware of observer bias ourselves (Dettwyler 1991).  As such researchers should always be clear who they are addressing, and the possible differences highlighted, where evidence is available, as to how a disabled person was treated within their culture when archaeological or cultural evidence is available.

To complicate the matter further is the ‘osteological paradox‘, as highlighted by Larsen (1997), Woods et al. (1992) and Wright & Yoder (2003) amongst others, which heavily influences the health status of skeletal remains that survive and that are then studied.  Therefore it should always be understood that no skeletal sample is entirely representative of their population, that there are many caveats (Hahn 1995, Roberts 2000).

Battles (2011) highlighted the need to move towards a more holistic approach to disability, to take advantage of different fields (including physical anthropology, sociocultural anthropology, experimental studies and archaeology itself) to understand disability at archaeological sites and affected individuals, to a model that integrates the data and insight of the various fields.  In particular Battles (2011) makes the salient point of noting the individuals  (largely females and sub-adults) that historically have been under-studied in archaeological and population analyses.

An important methodological update has been the advancement of a ‘Bioarchaeology of Care‘, as espoused by Tilley & Oxenham (2011), where a four stage assessment of an individual produces an assessment of the care needed for the disabled individual found in a Neolithic Vietnam community.  The stages are: (1) describing,  diagnosing and documenting the individual and site, (2) identify the clinical/functional impacts of disease or trauma, and determine if care was needed, (3) produce a model of care, and finally (4) interpret the implications for the individual and society, as well as possible indications for the identity and nature of both (Tilly & Oxenham 2011: 36).  It could be argued that other researchers have espoused the same sentiments (Roberts & Manchester 2010, Vilos 2011), but it is the clear initiation of the applying the model to individuals who fit the criteria that will hopefully produce further studies and elicit meaningful result which highlight this recent study as one to watch.  The Tilley & Oxenham (2011) model is particularly useful for prehistoric cases where there are no written or documentary sources.

Hawkey’s (1998) study of musculoskeletal markers (MSM’s) of a disabled individual from a New Mexico Pueblo culture highlighted the worth of applying existing osteological techniques to disabled individuals in order to assess the quality of bodily movement.  The modelling of the movement capable for this individual suggested that bodily manipulation, feeding, and the cleaning of this person was likely carried out by members of his culture (possibly family relatives, although this is conjecture) due to the severity of his disability (Hawkey 1998: 330).  Craig & Craig (2011) make extensive use of modern medical imaging to diagnosis a specific disease (fibrous dysplasia) in the case of a sub-adult from an English Anglo-Saxon site.  The striking bone expansion in the mandible is discussed within the social sphere of the community that the individual belonged.  The implications, via the the inference of position of the body within the grave, grave goods and grave location, and studies into Anglo-Saxon culture and social stratification give rise to the theory that the individual was not treated any differently due to his disability, although it is unknown if the disease led to the early demise of the individual (Craig & Craig 2011: 3).

Craig & Craig’s (2011) case study, and the above studies, highlight the use of modern medical literature and imaging technology in establishing a likely disease diagnosis, yet Brothwell (2010) rightly highlights the dangers of the differential diagnosis of diseases in skeletal remains at a macroscopic level.  Waldron’s (2009) palaeopathology handbook presents an ideal source on how to identify diseases that can lead to disability, but highlights the value of the differential diagnosis when the osteologist cannot be exactly sure of the disease.

The battery of scientific techniques used in archaeological investigations, including aDNA analysis, trace chemical analysis, and isotopic analysis amongst others, have become significantly refined within the past two decades, and are now allowing for a more nuanced understanding of individual and population dynamics (Brown & Brown 2011).  This includes the ability to analysis the movement of a person in a landscape within their lifetime (Marstellar et al. 2011), and to understand the changes in diet and the effects of diet on the body (Larsen 1997, Roberts 2000, Roberts & Manchester 2010). It also includes the ability to indicate the likely exposure of populations to various chemicals and diseases (Barnes et al. 2011), and exploration of how social structure (Bentley et al. 2012), and hence the role of the population or of the individual, changed through time.

Perhaps what the above studies cannot show, especially in prehistoric societies, are the actions of the disabled individuals themselves.  It is most likely that we will never know if they took an active interest in their society, if they took part, or how they felt as disabled individuals, or even if they saw themselves as disabled (Battles 2011, Hahn 1995).  Compassion  itself cannot be excavated (Dettwyler 1991), but with careful examination of the available evidence results can be produced that suggest that severely disabled individuals did survive past natural limitations.

The progress continually being made in the hard sciences and in the humanities continues to advance our knowledge of past populations via their skeletal remains and their cultural context.  The understanding of disability within an archaeological and osteological context provides the opportunity to investigate of how individual’s survived, and whether care was a key component (Hawkey 1998, Kleinman 1978, Tilley & Oxenham 2011).  This is a burgeoning area of bioarchological research, and when combined with a multidisciplinary approach, it opens up a wide range of interesting and diverse approaches and avenues.

Case Studies, Theories and Further Information:

Full articles are linked where possible, although a number hide behind Journal pay walls.

Aufderheide, A. C. & Roderiquez-Martin, C. 1998. The Cambridge Encyclopedia of Human Palaeopathology. Cambridge: Cambridge University Press.

Barnes, I., Duda, A., Pybus, O. G. & Thomas, M. G. 2011. Ancient Urbanization Predicts Genetic Resistance to Tuberculosis. Evolution. 65 (3): 842-848.

Battles, H. 2011. Toward Engagement: Exploring the Prospects for an Integrated Anthropology of Disability. Explorations in Anthropology. 11 (1): 107-124.

Bentley, R. A., Bickle, P., Fibiger, L., Nowell, G. M., Dale C. W., Hedges, R. E. M., Hamiliton,. J., Wahl, J., Francken, M., Grupe, G., Lenneis, E., Teschler-Nicola, M., Arbogast, R-M., Hofmann, D. & Whittle, A. 2012. Community Differentiation and Kinship Among Europe’s First Farmers. Proceedings of the National Academy of Sciences Early Edition. 1-5. (Early View).

Brothwell, D. 2010. On problems of Differential Diagnosis in Palaeopathology, as Illustrated by a Case from Prehistoric Indiana. International Journal of Osteoarchaeology. 20: 621-622.

Brown, T. & Brown, K. 2011. Biomolecular Archaeology: An Introduction. Chichester: Blackwell Publishing.

Churchill, S. E., Franciscus. R. G., McKean-Peraza, H. A., Daniel, J, A. & Warren, B. R. 2009. Shanidar 3 Neandertal Rib Puncture Wound and Palaeolithic Weaponry. Journal of Human Evolution. 57: 163-178.

Craig, E. & Craig, G. 2011. The Diagnosis and Context of a Facial Deformity from an Anglo-Saxon Cemetery at Spofforth, North Yorkshire. International Journal of Osteoarchaeology. (Early View doi: 10.1002/oa.1288).

Dettwyler, K. A. 1991. Can Palaeopathology Provide Evidence for “Compassion”? American Journal of Physical Anthropology. 84: 375-384.

Fashing, P. J. & Nguyen, N. 2011. Behaviour Towards the Dying, Diseased, or Disabled Among Animal and its Relevance to Palaeopathology.  International Journal of Palaeopathology. 1: 128-129. 

Hahn, R. A. 1995. Sickness and Healing: An Anthropological Perspective. New Haven: Yale University.

Hawkey, D. E. 1998. Disability, Compassion and the Skeletal Record: Using Musculoskeletal Stress Markers (MSM) to Construct an Osteobiography from Early New Mexico. International Journal of Osteoarchaeology. 8: 326-340.

Hublin, J. J. 2009. The Prehistory of Compassion. Proceedings of the National Academy of Sciences. 106 (16): 6429-6430.

Kleinman A. 1978. Concepts and a Model for the Compassion of Medical Systems as Cultural Systems. Soc Sci Med. 12: 85-93.

Knusel, C. J. 1999.  Orthopaedic Disability: Some Hard Evidence. Archaeological Review Cambridge. 15: 31-53.

Larsen, C. 1997. Bioarchaeology: Interpreting Behaviour from the Human Skeleton. Cambridge: Cambridge University Press.

Larsen, C. S. 2002. Bioarchaeology: The Lives and Lifestyles of Past Peoples. Journal of Archaeological Research. 10 (2): 119-166.

Marstellar, S. J., Torres-Rouff, C. & Knudson, K. J. 2011. Pre-Columbian Andean Sickness Ideology and the Social Experience of Leishmaniasis: A Contextualised Analysis of Bioarchaeological and Palaeopathological Data from San Pedro de Atacama, Chile. International Journal of Palaeopathology. 1 (1): 23-34.

Mays, S. 2012. The Impact of Case Reports Relative to Other Types of Publication in Palaeopathology. International Journal of Osteoarchaeology. 22: 81-85.

Roberts, C. A. 2000. ‘Did They Take Sugar? The Use of Skeletal Evidence in the Study of Disability in Past Populations’. In Hubert, J. (ed) Madness, Disability and Social Exclusion: The Archaeology and Anthropology of Difference. London: Routledge. 46-59.

Roberts, C. & Manchester, K. 2010. The Archaeology of Disease. Stroud: The History Press.

Stewart, F.A., Piel, A.K., O’Malley, R.C., 2012. Responses of Chimpanzees to a Recently Dead Community Member at Gombe National Park, Tanzania. American Journal of Primatology. 74: 1–7.

Tilley, L. & Oxenham, M. F. 2011. Survival Against the Odds: Modelling the Social Implications of Care Provision to the Seriously Disabled. International Journal of Palaeopathology. 1 (1): 35-42.

Vilos, J. D. 2011.  Bioarchaeology of Compassion: Exploring Extreme Cases of Pathology in a Bronze Age Skeletal Population from Tell Abraq, U. A. E. Master’s Dissertation. Las Vegas: University of Nevada.

Waldron, T. 2009. Palaeopathology. Cambridge: Cambridge University Press.

Wood, J. W., Milner, G.R., Harpending H. C., & Weiss, K. M. 1992.  The Osteological Paradox: Problems of Inferring Prehistoric Health from Skeletal SamplesCurrent Anthropology 33:  343-370.

Wright, L. E. & Yoder, C. J. 2003.  Recent Progress in Bioarchaeology: Approaches to the Osteological ParadoxJournal of Archaeological Research 11 (1): 43-70. (**An extensive bibliography of articles can be found in the bibliography of this article**).

An Introduction to Fibrous Dysplasia & McCune-Albright Syndrome

28 Oct

Definition of Fibrous Dysplasia: ‘Fibrous dysplasia is a non-inherited metabolic bone disease in which abnormal differentiation of osteoblast maturation (which) leads to replacement of normal marrow and cancellous bone by immature bone and fibrous stroma’ (Fitzpatrick et al 2004: 1389).  Fibrous Dsyplasia (FD) can be described as either monostotic (one) or polyostotic (many), depending on how many bones are affected by the disease.  Fibrous Dysplasia lesions are often displayed as having a ‘ground glass‘ appearance on x-rays and are a distinctive radiographic feature of the disease, although it is not pathognomonic of it (Waldron 2009).  It is also noted that pathological fractures are a key defining feature of polyostotic Fibrous Dysplasia (Marsland & Kapoor 2008).  FD is described as a rare disease, with the monostotic form being more prevalent than the polyostotic form.

Definition of McCune-Albright Syndrome:  McCune-Albright Syndrome (MAS) was originally typically diagnosed and recognised when a person had any of the two of the triad of the following symptoms: polyostotic Fibrous Dysplasia, Cafe-au-lait marks and/or precocious puberty.  However it was later recognised that ‘endocrinopathies, including hyperthyroidism, growth hormone excess, renal phosphate wasting with or without rickets/osteomalacia, and Cushing Syndrome’  could be found in association with the original triad (Dumitrescu & Collins 2008: 1).  In all three systems (skin, skeletal & endocrine), the presentation and abnormality can be highly variable from person to person depending on the tissues involved and the extent of the involvement (OMIM-see below).  Estimated prevalence is 1/100,000 to 1/1,000,000, it is such a wide margin because no thorough prevalence study has been carried out in recent times (Dumitrescu & Collins 2008: 1).

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As a person who happens to have McCune Albright syndrome, to have known to have it from the first years of life, I have become somewhat forgetful of its origin: that somewhere in the early postzygotic  divisions of my life, the disease appeared and became a part of me.  Although I am aware each day of the ramifications that the mutation of the GNAS1 gene has caused I often consider myself lucky.  Lucky in the fact that in my case it has only led to broken bones and various surgeries rather than the full expression of the endocrinopathies that can occur.  I use a wheelchair for everyday mobility with limited use of crutches, mostly used for aiding inside mobility (and sometimes excavations!).

In my personal case, the disease has most affected the main weight-bearing bones of the lower limbs (fairly typical as they are the stress bearing bones, prone to fracture from weakened bone architecture).  Generally speaking,the long bones of the appendicular skeleton tend to be bowed naturally with a pathological weakness due to the lack of normal bone density and high bone cell turnover, with the aforementioned bone lesions occurring spontaneously which sometimes lead to fracture.  This includes the bilateral deformity of the femora with which I’ve had numerous pathological fractures (Five natural transverse fractures, five elective surgery initiated) on both the left and right sides, alongside a number of fractures of the right tibia and fibula (including both transverse and hairline fractures), two on the right humerus and the 5th metatarsal in the right foot.  The shepherd’s crook deformity is the common bowing deformity with varus angulation of the proximal femur (Fitzpatrick et al 2004: online).

As stated the primary bones affected by the MAS pathological fractures are typically located in the appendicular skeleton and include the following bones in order of prevalence first:  a) femur, b) tibia, c) fibula, d) humerus and e) the ribs.  It can also affect the craniofacial skeleton with distinct abnormalities in the amount of bone growth and deformity; however this tends to lessen with age after the primary and secondary growth periods (adolescence and sexual maturity), or ‘burn out’ as it is often called by medical specialists (Dumitrescu & Collins 2008: 8).

‘An example of the shepherds crook’ deformity of the femoral neck (coxa vara) with internal fixation.

My experiences of living with McCune Albright syndrome has included numerous hospitalizations due to fractured bones and planned corrective surgeries.  This has also included large amounts of time stuck in my old friend the Thomas Splint in bed bound traction, alongside enduring a host of various corrective surgical procedures to improve the angulation of both femoral necks.  Although the initial idea following a number of fractures was to treat the femoral deformities with an Ilizarov apparatus by manipulating the bone growth every day, it was quickly decided that an intramedullary rod (nicknamed the Sheffield Rod), carried out in conjunction with osteotomies to correct the femoral neck angle during surgery, would be a much safer and further reaching goal in stabilising both femoral necks in the long term.  (A rather wonderful digital video of a rod being inserted/hammered in can be viewed here).  Five major elective intramedullary rod surgeries later (3 for the left femur and 2 for the right femur!), and it seems as if they have thus far stabilised each femoral shaft/neck enough for them not to fracture again.  However this is also due to using the wheelchair much more extensively than before!

I also have had surgery to stabilise the right tibia and fibula.  This was decided after having undergone three accidental fractures of the right tibia and fibula with a space of 5 years (when the tibia breaks the fibula often follows because of their connection via the interosseous membrane), with each fracture requiring many months in plaster in order for the bone to heal.  Again this surgery included osteotomies of the tibia and fibula to improve the angle of the bone (and thus improve the bio-mechanical loading of the lower leg) and included the fixation of the tibia by means of a titanium plate.  It was hoped that an intramedullary rod could be inserted into the tibia after the tibial osteotomy but the risk of massive blood loss (an outcome of the porous bone and increased heartbeat/blood flow) and the presence of porous cortical bone meant that the tibia was probably unlikely to be able to ‘hold’ the rod in place.

I have also fractured the right humerus twice, with the second transverse fracture resulting in the fixation of the humerus with a permanent titanium plate and associated screws.  This is similar to my right tibia which has a permanent titanium plate and screws to fixate the bone and alleviate some of the pressure of walking.

I have undertaken treatment using biphosphonphates (in my case the drug pamidronate) to increase the bone density itself over a number of years in the past when I was a teenager, but the resultant bone density scans (taken at intervals before, during and after the treatment) showed little improvement and treatment was subsequently stopped.  Upon further reading into this it seems there are possible problems for long term users of biphosphonates.   This can include the higher risk of fracture after long term use due to the bodies inability to metabolize the drug and the natural effect of the biphosphonate inhibition on the bone cell turnover rate (Ott 2005: 31897).  There are many cases though where drug treatment has proved beneficial; however each case should be merited individually and each person monitored as appropriate.  I will stress here that there are many different types of biphosphonates available and that McCune Albright Syndrome varies in its intensity.

X ray of my left femur and hip with a locking intramedullary rod and screws.  Although please note that two of the femoral neck screws have now been taken out.

Although this is just a short post on the introduction to the disease that is sharing life with me it can also be found in the archaeological record.  Waldron (2009: 214) points out that Fibrous Dysplasia is often best diagnosed in an archaeological skeleton by the noting of either a shepherd’s crook deformity, healed fractures and findings of expansile swellings on one or more bones.  Subjecting the suspected sample to X-ray should show ‘lucent areas with endosteal scalloping and sometimes a thick sclerotic border’  (Waldron 2009: 215).  Unlike today’s vast array of modern medical treatment and surgical procedures, people in the past largely had to make do and mend.

As Roberts & Manchester (2010) discuss in their book, fracture treatment in the medieval age and before was fairly adept at helping in supporting and stabilising the fracture site.  However with repeated breaks in the main weight supporting bones, it is doubtful whether one could have led a normal life if the fractures were not reduced properly or repeatedly after continual breaks (Oakley 2007).  It also should be noted here that due to the nature of McCune Albright Syndrome it is unlikely to be described in the archaeology record as human skin rarely preserves.  It is far more likely that Fibrous Dysplasia is diagnosed based on the skeletal remains.

In the archaeological record Fibrous Dysplasia remains a rare and elusive disease to diagnose, whilst is has actively been described and documented in more recent human remains (Nerlich et al. 1991).  The following two case studies highlight individual cases of where Fibrous Dysplasia has been documented in archaeological material.

A recent case study presented by Craig & Craig (2011) discusses a juvenile skeleton with evidence of polyostotic Fibrous Dysplasia.  The skeletal remains of a child aged 7 years presents with Fibrous Dysplasia with evidence of involvement most noticeable with large bone expansion on the left mandible alongside involvement of the temporal, maxilla, parietal and frontal craniofacial bones.  A review of the burial context of the skeleton and of the Anglo-Saxon cemetery population that the child comes from shows no differentiation between this and other burials, indicating no differentiation in the disposition of this child’s body or associated grave goods.  Craig & Craig (2011) also cite further Ango-Saxon literature to suggest that it is highly unlikely that the child was stigmatized due to his disability, although we can never know for sure.

Recent evidence in a 120,000 year old Neandertal individual from the Upper Pleistocene site of Krapina in present day Croatia highlights the likely evidence for Fibrous Dysplasia presence in a small rib fragment (Monge et al. 2013).  This is extremely rare to find a bone lesion or tumour  in skeletal material from such a period and it is extremely exciting.  The rib was allocated original as a faunal remain when the site was initially excavated, but the rib was recognised for being of Neandertal origin by sharp eyed human osteology legend Tim D. White (Monge et al. 2013).

X ray of the transverse fracture of my right tibia and fibula in the summer of 2009.  This was the first of three transverse fractures of the right tibia and fibula that followed in quick succession over a short number of years, and resulted in the fixation of the tibia with a permanent titanium plate.

Below are some medical and non-medical sources of information on the various aspects of both Fibrous Dysplasia & McCune Albright Syndrome (FD and MAS). This includes a few recent palaeopathology articles that are freely available, medical articles discussing both FD and MAS, core palaeopathology textbooks and support groups in the US and UK for sufferers of the bone disease.  Although the disease is not headline grabbing news, the lack of research into the socio-economic aspects of the disease is distinctly lacking, as is the number of foundations or adult support services for sufferers with the disease.

I am thankful for the support of my friends, family & my consultant in the treatment of this syndrome and for continued support given.

N.B. The origin of the Ilizarov frame is particularly interesting.  It was first used in the 1950s in the USSR, with Dr Gavril Ilizarov originally using bicycle wheel spokes to fixate, support and lengthen badly fractured bones.  It was only introduced to the West in the 1980’s as a direct result of Ilizarov’s corrective surgery on a patient in Italy when all other options had failed in healing the patient’s fractures.  So far I have managed to avoid having the frame but it is still a standard procedure for badly fragmented fractures, in particular it is often used after motorbike accidents or reconstructing limb angulation/length.

Bibliography and Further Sources:

Fibrous Dysplasia:

Medical Articles:

  • Lee, J. S. FItzgibbon, E. J., Chen, Y. R., Kim, H. J., Lustig, L. R., Akintoye, S. O., Collins, M. T. & Kaban, L. B. 2012. Clinical Guidelines for the Management of Craniofacial Fibrous Dysplasia. Orphanet Journal of Rare Disease. 7 (1): 1-19..
  • Marsland, D. & Kapoor, S. 2008. Rheumatology and Orthopaedics. London: Mosby Elsevier.

McCune-Albright Syndrome:

Medical Articles:

Palaeopathology:
  • Aufderheide, A. C. & Rodríguez-Martín. C. 1998. Cambridge: Cambridge University Press. (pg.420-421).
  • Roberts, C. & Manchester, K. 2010. The Archaeology of Disease Third Edition. Stroud: The History Press.
  • Waldron, T. 2009. Palaeopathology: Cambridge Manuals in Archaeology. Cambridge: Cambridge University Press.
General Medical
  • Pub Med, a US National Library of Medicine website.

The Origins of Tuberculosis & Smallpox

3 Jun

The following articles cited were brought to my attention by the good work of Confusedious: A Science Blog, and his entries on TB and its  possible origin.

Surprising Origins of Tuberculosis & Smallpox

Recent genetic investigations into the origin of the above diseases, of the chromosomes in TB and the study of smallpox’s ‘biological clock’, has revealed interesting information regarding their origin.   TB and Smallpox were previously thought caused or at least had its early origins during the domestication of animals, and by the dense urbanisation of human populations, first seen during the Mesolithic to Neolithic transition (Tuberculosis- Barnes et al 2011, Larsen 1997, Roberts & Manchester 2010, Smith et al 2009, Smallpox- Li et al 2007, Waldron 2009).

Compression Of Vertebrae As An Effect Of TB

Tuberculosis was originally thought to be spread from bovine at the period of domestication, with the strains M. Tuberculosis and M. Bovis to be considered the main organisms for TB infection in humans.  New genetic research has led to distinguish that M. Tuberculosis did not evolve from M. Bovis at the time of domestication of animals as a direct zoonosis; however it must be remembered that ‘it is probable that a necessary condition for its transference from animal to human is the close association between the two’ (Roberts & Manchester 2010: 184, Smith et al 2009).  I’d imagine the intensification of the Neolithic domestication undoubtedly led to higher rates of cross-species infection.  Research has also shown that the Mycobacterial Tuberculosis strain appeared some 15,300-20,400 years ago, well before the domestication of the earliest animals (Roberts & Manchester 2010: 185).  However there is no doubting the record that during the Neolithic, and up to the present day, that TB has damaged numerous lives.  The effects of TB on the human body can produce results found in osteological remains (Waldron 2009).  This will be discussed in a later blog entry on diseases found in human bones.

The threat of smallpox, a unique infectious disease to humans, was wiped out in AD 1980, but its origins are mysterious.  As Roberts & Manchester (2010: 181) note smallpox (Variola major or minor) ‘would obviously need highly populated urban areas for its success…and it is unlikely it was a problem until urbanization occurred’.  Recent genetic investigations into the origin of the Variola major/minor have discovered that it likely diverged from an ancestral African rodent-borne Variola-like virus either 68,000 to 16,000 BP (Li et al 2007).  However, it is well known that in its most virulent form in humans as smallpox, it has ravaged human urbanised populations for at least 2000 years, and is definitely dated to 10,000 BP.  Curiously, from documentary data and archaeological data, it seems there is a particular lacking of recorded smallpox cases in ancient Greece and ancient Rome (Roberts & Manchester 2010).

The Effects of Smallpox Decimated The Americas When The Europeans Helped Spread the Disease in the 16th Century, As Depicted In This, The Florentine Codex.

New genetic data is providing the backdrop for how infectious diseases spread, and more about their origin.  It is also helping scientists develop past population pathways for infection routes and rates (Jurmain et al 2011).It is apparent that new genetic data has opened up a whole raft of new research potentials into the origins and evolution of tuberculosis, and the relationship before, during and after the domestication of animals.

Bibliography:

Barnes, I.Duda, A. Pybus, O. G. Thomas, M. G. 2011. ‘Ancient Urbanization Predicts Genetic Resistance To Tuberculosis’. In Evolution. 65 (3): 842-848. Blackwell Publishing: London.

Jurmain, R. Kilgore, L. & Trevathan, W.  2011. Essentials of Physical Anthropology International Edition. London: Wadworth.

Li, Y. Carroll, D. S. Gardner, S. N. Walsh, M C. Vitalis, E. A. & Damon, I. K. 2007. ‘On The Origin of Smallpox: Correlating Variola Phylogenics with Historical Smallpox Record’. In PNAS. 104 (40). October 2nd.  15,787-15,792.National Academy of Sciences: Wisconsin.

Roberts, C. & Manchester, K. 2010. The Archaeology of Disease Third Edition. The History Press: Stroud.

Smith, N. H. Hewinson, R. G. Kremer, K. Brosch, R. & Gordon, S. V. 2009. ‘Myths and Misconceptions: The Origin and Evolution of Mycobacterium tuberculosis’. In Nature Reviews: Microbiology. Vol 7. 537-544. Macmilan Publishers Limited: London.

Waldron, T. 2009. Palaeopathology: Cambridge Manuals in Archaeology. Cambridge:Cambridge University Press.