Bony involvement of the skull is apparent such manifestations as porotic hyperostosis. .
Iron-Deficiency Anemia .
Iron-deficiency anemia appeared in some cultures evidenced as cribra orbitalia and porotic hyperostosis (Gerszten et al. 1997; Blom et al. 2004; Moseley, 1965; Moodie, 1929). The presence of the aforementioned bony reaction implies that chronic childhood anemia is the culprit. 25% of subadult remains examined by Gerszten et al. (1997) showed evidence of porotic hyperostosis. In some earlier studies, symmetrical osteoporosis of the cranial vault, especially the frontal is similar in appearance to the bony involvement of iron-deficiency anemia. In 1965, it was cited that Peruvian coastal infant populations had high frequencies of this paleopathology, as observed by Hrdlika in 1910 (Moseley). The areas affected are similar to those of chronic iron-deficiency anemia, located on the roof of the orbits (cribra orbitalia), "on each side of the frontal squama between frontal tuberosity and the coronal suture" (Moseley, 1965). .
Blom et al. (2004) studied an extensive collection of pre-Columbian skeletal remains, consisting of 1465 individuals from widely distributed latitudinal South American localities. Blom et al. (2004) found regional and dietary causes for chronic childhood anemia. Lowland skeletal remains exhibit higher numbers of porotic hyperostosis as well as a mixed diet of maize and marine resources yield higher frequencies of porotic hyperostosis, the prime "indicator of the bodies' attempt to overcome childhood anemia." .
Deafness .
Deafness, a result of occupational hazards is visible in exotoses of the external auditory canal, this has only been observed to occur in coastal populations-indicative of an occupational stressor. Exotoses of the auditory canal occurs as a reaction to chronic ear infection, the infection is a result of shellfish diving. Coastal populations that rely on diving for fish as a subsistence economy resulted in the continuous exposure to ear infection, thus creating a chronic disease.
