Paleopathology, also spelled palaeopathology, is the study of ancient diseases and injuries in through the examination of , Mummy, skeletal remains, and analysis of . Specific sources in the study of ancient human diseases may include early documents, illustrations from early books, painting and sculpture from the past. All these objects provide information on the evolution of diseases as well as how past civilizations treated conditions. Studies have historically focused on humans, although there is no evidence that humans are more prone to pathologies than any other animal.
The word paleopathology is derived from the Ancient Greek roots of palaios (παλαιός) meaning "old", pathos (πάθος) meaning "experience" or "suffering", and -logia (-λογία), "study".
Paleopathology is an interdisciplinary science, meaning it involves knowledge from many sectors including (but not limited to) "clinical pathology, human osteology, epidemiology, social anthropology, and archaeology". It is unlikely that one person can be fluent in all necessary sciences. Therefore, those trained in each are important and make up a collective study. Training in anthropology and archaeology is arguably most important, because the analysis of human remains and ancient artifacts are paramount to the discovery of early disease.
From the Renaissance to the mid-nineteenth century, there was increasing reference to ancient disease, initially within Prehistory animals although later the importance of studying the antiquity of human disease began to be emphasized. Some historians and anthropologists theorize that "Johann Friederich Esper, a German naturalist...heralds the birth of paleopathology." Although it wasn't until between the mid nineteenth century and World War I that the field of human paleopathology is generally considered to have come about. During this period, a number of pioneering physicians and anthropologists, such as Marc Armand Ruffer, G. Elliot Smith, Frederic Wood Jones, Douglas E. Derry, and Samuel George Shattock, clarified the medical nature of ancient skeletal pathologies. This work was consolidated between the world wars with methods such as radiology, histology and serology being applied more frequently, improving diagnosis and accuracy with the introduction of statistical analysis. It was at this point that paleopathology can truly be considered to have become a scientific discipline.Aufderheide, A.C and Rodríguez-Martín, C. 1998. The Cambridge Encyclopedia of Human Paleopathology. Cambridge: Cambridge University Press. Today, the use of biomedical technology like DNA and isotopic analysis are major developments for pathological knowledge.
After World War II paleopathology began to be viewed in a different way: as an important tool for the understanding of past populations, and it was at this stage that the discipline began to be related to epidemiology and demography.
New techniques in molecular biology also began to add new information to what was already known about ancient disease, as it became possible to retrieve DNA from samples that were centuries or millennia old.
Whilst traumatic injuries such as broken and malformed bones can be easy to spot, evidence of other conditions, for example infectious diseases such as tuberculosis and syphilis, can also be found in bones. Arthropathies, that is joint diseases such as osteoarthritis and gout, are also not uncommon.
The first exhaustive reference of human paleopathology evidence in skeletal tissue was published in 1976 by Ortner & Putschar.Ortner, Donald J. and Walter G. J. Putschar. 1981. Identification of Pathological Conditions in Human Skeletal Remains. Washington: Smithsonian Institution Press. In identifying pathologies, physical anthropologists rely heavily on good archaeological documentation regarding location, age of site and other environmental factors. These provide the foundation on which further analysis is built and are required for accurate populations studies. From there, the paleopathology researcher determines a number of key biological indicators on the specimen including age and sex. These provide a foundation for further analysis of bone material and evaluation of lesions or other anomalies identified.
Archaeologists increasingly use paleopathology as an important main tool for understanding the lives of ancient peoples. For example, cranial deformation is evident in the skulls of the Maya peoples, where a straight line between nose and forehead may have been preferred over an angle or slope. There is also evidence for Trepanning, or drilling holes in the cranium, either singly or several times in a single individual. Partially or completely healed trepanations indicate that this procedure was often survived. The 10,000 year-old human remains discovered at the site of Nataruk in Turkana, Kenya, reportedly show extreme traumatic lesions to the head, neck, ribs, knees and hands, including embedded stone projectiles, and they may represent the earliest evidence of inter-group conflict between hunter-gatherers in the past.
All these different types of trauma may be the result of accident, interpersonal violence, cultural practice or therapeutic treatment.
Bone fracture are the result of enough force being applied to bone to mechanically alter it. Tension, compression, torsion, and bending or shearing each leave its own characteristics on skeletal remains. The type, severity, number, timing and location of fractures are important for delineating between accidental and violent trauma and the data recovered from analysis reveal the meaning of that violence.
Types of trauma encountered during analysis might include Blunt trauma (BFT), sharp force trauma (SFT), projectile, heat, and chemical. Evidence of trauma in skeletal remains can vary depending on the type of bone affected; for example, blunt force trauma from a club will present differently than sharp force trauma inflicted by a sword.
During analysis, evidence of antemortem (before death) healing of a fracture allows it to be compared with both perimortem (around time of death) and postmortem (after death) trauma. Antemortem healing will present as a callus at the location of the fracture. As White notes, “The rate of fracture repair depends on alignment, amount of movement at the site of fracture and the health, age, diet, and blood supply of the individual.”
Apart from bones, molecular biology has also been used as a tool of paleopathology over the last few decades, as DNA can be recovered from human remains that are hundreds of years old. Since techniques such as PCR are highly sensitive to contamination, meticulous laboratory set-ups and protocols such as "suicide" PCR are necessary to ensure that false positive results from other materials in the laboratory do not occur.
For example, the long-held assumption that bubonic plague was the cause of the Justinian plague and the Black Death has been strongly supported by finding Yersinia pestis DNA in mass graves, whereas another proposed cause, anthrax, was not found.
In 2013 an excavation at Thornton Abbey in North Lincolnshire uncovered a mass grave of 48 people, including 27 children. Radiocarbon dating and artifacts found in the mass grave showed that the bodies were from the time of the Black Death. The wide range of ages of the remains, from one to 45 years, led archaeologists to infer that something devastating most likely caused their deaths. Typically, mass graves contain remains from either the very young or the very old; this was not the case here. Because all ages were being buried here, archaeologists inferred that, although Thornton Abbey was adjacent to a small town, it was consumed by the plague to the extent in which a mass grave was needed. Until this discovery, mass graves were very rare because small towns seemed to bury their dead in usual ways. It is believed that mass burials were used in Europe during this time because of the overwhelming number of deaths caused by the Black Plague.
Teeth samples from the remains revealed the presence of plague bacteria. These samples showed the presence of Y. pestis DNA, the bacterial cause of the plague. "Molecular identification by 'suicide PCR' of Yersinia pestis in the pulp tissue of teeth" and other forms of analysis on ancient DNA has become progressively more common with modern advancements.
Tuberculosis manifests itself in the archaeological record through DNA extraction from the skeletal remains of people. Tuberculosis rarely manifests itself in the skeleton of individuals and when it does, it is usually only in advanced stages of the disease.Buikstra 2006, pg. 310 and 364 The tuberculosis bacteria stays in the growth centers and spongy areas of the bone. Tuberculosis can lie dormant for long periods of time; because of the long period of development in the body, tuberculosis damages the body and then the body has time to repair itself. The evidence of the disease in bones can be seen in the destruction and healing of the bone structures especially in joints. Tuberculosis therefore appears in the archaeology record in the knee and hip joints and also the spine.
It was thought that there was no tuberculosis infection in North America before the arrival of Europeans, but recent findings from the 80s and 90s have overturned that idea.Buikstra 2006, pg 307 Through extraction of DNA within the bone tuberculosis was not only found, but also dated to have been present in the Americas since 800 BC. Tuberculosis is a disease that thrives in dense populations; the implication of finding tuberculosis in pre-Columbian society is that there was a large thriving community at the time.Roberts 1995, pg. 141 The earliest evidence of tuberculosis has been found in Italy dating to the 4th millennium BC. Evidence of tuberculosis has also been found in mummies from ancient Egypt dating to the same period. There is however, a lack of medical texts from ancient European and Mediterranean regions describing diseases that are identifiable as tuberculosis but the bones show that there was a disease of this type.Roberts 1995, pg. 139
Bone changes can be seen in the archaeological record through lesions on the surface on the bone. In venereal syphilis the bone change is characterized by damage to the knees and joints. The damaged joints could be the source of infection or they could be damaged because of disruption in the nervous systems and ability to feel.Roberts 1995, pg 153 In the beginning stages of the disease, the bone forms small lesions on the skull and tibiae. These lesions are caused mostly by inflammation of the marrow. In the final stages of the disease the bones start to be destroyed. Lesions that are formed tend to look similar to "worm holes" in the bone and are seen in the skull as well as large bones in the body. Most of the bone that is destroyed is due to secondary infections.
Syphilis has been seen in the Americas and Europe alike but there is debate as to what the origin of the disease is. Columbus and his sailors were said to have brought it to the Americas, however, Europeans blame Columbus for bringing the disease to Europe. There has not been any evidence of bone lesions associated with the disease that Columbus and the Europeans describe.Janssens 1970, pg 104 The debate on the origins of venereal syphilis has been the subject of scientific discussions for hundreds of years and has recently been discussed and debated. At the first International Congress on the Evolution and Paleoepidemiology the subject was examined and debated by scholars from all over the world. There was no conclusive decision made as to the origin of venereal syphilis.
Methods and techniques
Trauma analysis in paleopathology
Skeletal trauma
Violence
Archaeological infectious diseases
Black Death
Tuberculosis
Syphilis
See also
Footnotes
External links
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