The California coast and the associated Channel Islands provide a counterpoint to the other core groups discussed in this volume. They were not agricultural, but instead foraged and fished as a means of subsistence. The Channel Island chronologies are usually split into early versus late components. Health comparisons have been conducted between these two groups.
The presence and timing of linear enamel hypoplasias have been used to infer childhood stress (or physiological disruptions) and when that stress occurred (Figure 4.2). Linear enamel hypoplasias have been shown to be higher in agriculturalists.
FIGURE 4.2 This photo shows the linear enamel hypoplasias (LEH) that are visible in adult teeth but that were effected by some type of stress while those teeth were forming in early childhood (between the ages of 1—6). Specimen ID: AFIP 1002959. Source collection: Anatomical division. From National Museum of Health and Medicine, Otis Historical Archives via Flickr, http://creativecommons.org/licenses/by/4.0/.
Cohen and Armelagos (1984: 573; reprinted 2013) reviewed 19 case studies of ancient populations undergoing the shift from foraging to agriculture and summarized the findings this way:
[T]he incidence of physiological stress increases greatly and average mortality rates increase appreciably . . . most of these agricultural populations have high frequencies of porotic hyperostosis and cribra orbitalia, and there is a substantial increase in the number and severity of enamel hypoplasias and pathologies associated with infectious disease.
Although this pattern of increasing poor health is well documented, interpretations of why this is seen have been challenged over the years, and newer evidence from isotopes and better diagnostic criteria of disease has challenged some of the premises about what makes agriculture a less healthy human endeavor than foraging (Pinhasi and Stock 2011).
In contrast to the agriculturalists of the Lower Illinois RiverValley or the Southwest, the prevalence of linear enamel hypoplasias decreases with time for coastal California from 33% to 17% (Kerr 2004). Different islands were more subject to stressors than others as well. For example, San Nicolas Island individuals have more hypoplasias than other islands, indicating that children living there were exposed to more stress than the other islands.
In line with the decrease in linear enamel hypoplasias over time, there is also a reduction of caries (cavities) rates. Walker and Erlandson (1986) attribute this shift to a change from carbohydrate-rich tubers and roots to a more marine-based diet in the later periods of occupation. Geography also played a role in caries rates. In his dissertation, Bartelink (2006) compared caries rates between Sacramento Valley and the San Francisco Bay groups. He found that those groups living in the Sacramento Valley had higher caries rates regardless of period than those living in the San Francisco Bay, a difference attributed to the greater reliance on marine resources along the coast (San Francisco Bay).
There are sex differences in the expression of lesions related to stress and diet for all groups. One such difference can be seen in the expression of cribra orbitalia for the adult samples indicating that as children, males and females were exposed to different stresses (Lambert 1994). They possibly ate substantially different diets or had access to food sources in different amounts. Lambert (1994) also found that the percentage of individuals exhibiting cribra orbitalia (a condition of anemia) increased from the early to the late periods, from 13.8% to 30.6% of the total population. This may be related to climate change or to resource depletion brought on by population increases (Rick et al. 2005). As ecological conditions worsened and food became scarcer, the entire population showed more and more signs of nutritional stress. But women’s health suffered the most. It is also during this later period that violence becomes more prevalent. The same is true for dental pathologies such as antemortem tooth loss (Bartelink 2006). Children and adolescents also were exposed to violent interaction. Lambert (1994, 1997) found that individuals older than 10 years were more likely to exhibit trauma than those younger than the age of 10. This suggests a shift in the social identity of individuals at that age. They were included in activities after the age of 10 that exposed them to increased violent interaction, either with other adolescents or with the adult population.
When a child died, they would have probably been buried within a shell midden mound. These mounds would have also held domestic refuse, artifacts, house remains, and artifacts (Lightfoot and Luby 2012). Lambert (1993) notes that in mortuary samples from this area, children and adolescents were less common than adults. This may indicate that nonadults were buried using a different mortuary program and were not recovered as part of the normal excavations. The inclusion of at least some nonadults in the same mortuary program as adults, however, is intriguing. It suggests that there are possibly multiple burial programs present, and children were included in some but not all. This may indicate a ranked society (such as seen in the Lower Illinois RiverValley; see the following discussion) or that burial customs were highly regionalized.
Based on the data gleaned from larger analyses, a snapshot of what life was like in ancient California for children presents a nuanced picture. They would have been weaned onto starchy foods and marine resources, but this process was likely different for males and females. Adult females tend to have worse overall health indicators for stress, suggesting that they may have been exposed to more stress as children (Goodman and Armelagos 1988). Diet after weaning would have been dependent on local access. If they lived near the coast, they would have relied heavily on marine resources; if they lived farther from the coast, they would have relied more on starchy roots and tubers. Rites of passage occurred in their late childhood or early adolescence that would have changed their social standing within the community. In this case, that seems to have exposed them to increased levels of interpersonal violence.