Skeletal biologists who study disease and trauma in prehistoric remains are called paleopathologists. In prehistoric skeletons, numerous kinds of conditions have been recognized, including dental problems, infectious disease, neoplasms (cancer and other tumors), metabolic disorders (which typically affect growth), and degenerative arthritis and related conditions. In addition, paleopathologists are also interested in trauma, which can be recognized in skeletons in the form of broken bones or, occasionally, as weapon wounds.
Dental disease is the most common category of pathological conditions found in prehistoric remains. Commonly seen dental problems include extreme tooth wear (see Fig. 15-13), abscesses, and tooth loss. (For a very early example dating close to 2 mya, see Chapter 11, Fig. 11-7). Dental caries (cavities) were not common among hunter-gatherers prior to the adoption of agriculture, but with the introduction of new foods containing carbohydrates (especially grains such as corn or wheat), the frequency of caries increased dramatically. In fact, one “marker” of an agricultural lifestyle is the high frequency of caries.
As we have discussed in this chapter, infectious disease became the leading cause of death in human populations during the past few thousand years and, consequently, a major adaptive challenge for our species. Pale pathologists have found numerous examples of severe infectious diseases such as TB and syphilis. In the New World there are a few cases of TB and several examples of fungal diseases including “valley fever,” found in California and the American Southwest (Fig. 15-14).
Non‒life-threatening benign bone tumors are quite common, but only a few cases of severe cancer have been reported (Fig. 15-15). There are several possible explanations for the apparent rarity of cancer in the past: People died younger, on average, in prehistory, and cancer primarily affects older people. Also, many cancers don’t affect bone or do so only in advanced cases. Thus many individuals who may have had cancer died before it progressed to their skeletons. Moreover, exposure to environmental carcinogens was less common in prehistory than it is today.
Metabolic diseases such as rickets are most severe when they affect children during development (Fig. 15-16; also see Fig. 15-4, which shows rickets in a young child). Degenerative diseases include a wide variety of conditions, but those that directly affect the skeleton are colloquially referred to as “arthritis.” The most common location is the spine, especially in older individuals. The joints of the limbs, particularly hips and knees, are also frequently affected (Fig. 15-17).
As mentioned, paleopathologists also study trauma, which is found most typically in the form of healed fractures (Fig. 15-18). Fractures that occur at or very near the time of death exhibit no evidence of healing; therefore it’s difficult to distinguish such perimortem traumatic lesions from damage that occurred perhaps centuries after the death of the individual. (Post-mortem damage can occur any time burial sites are disturbed due to construction, agricultural activities, and many other factors.)
Wounds caused by weapons can be dramatic; even if they healed long before the person died, they are often still very obvious. Sometimes, if such injuries occurred shortly before or at death, it’s possible to determine cause of death, something that usually is not possible in archaeological material. For example, there are cases where arrow points have been found embedded in bones such as vertebrae or the cranium, with no sign of healing. In such a situation, it’s safe to assume that the person didn’t die of natural causes (Fig. 15-19). In several Old World sites, burials with injuries caused by metal weapons have also been found, particularly in battlefield cemeteries. Not surprisingly, these skeletons display many fatal injuries (Fiorato et al., 2000).
In August, 2012, archaeologists excavated the skeletal remains of an adult male in Leicester, England. As of this writing, there are no official publications regarding the skeleton, but it is likely to be that of King Richard III who died in battle in 1485. This is one of the most exciting archaeological discoveries in decades because it has the potential to answer questions about this infamous monarch that historians and others have been asking for 500 years. One near contemporary account states that Richard III was killed by a blow to the back of the head. The rear portion of this newly discovered cranium exhibits a severe injury and additionally a barbed, metal projectile point was found in the “upper back.” Last, the spine exhibits evidence of scoliosis and legend (strongly enhanced by Shakespeare) has always held that Richard III had a spinal deformity. Currently researchers are waiting for results of DNA analysis to help confirm the identity of this individual (Burns, 2012).