Demographic analysis of survivorship between Caucasian and Native American females in two temporally separated human populations buried in Emmet County, northern lower Michigan.

Abstract

A powerful tool for describing life patterns of individuals is the analysis of population demography. This study examined demographics for two temporally separated populations buried in six cemeteries throughout Emmet County, northern lower Michigan. The populations were defined as: (1) females who died between 1900 and 1945 inclusively, and (2) females who died between 1946 and 2000. I examined differences in survivorship between Caucasian and Native American females within the three separate populations, and differences in age-specific mortality rates for females of each ethnic group through time, across the populations. I determined age at death from the dates of birth and death marked on individual tombstones, and then recorded these data for each poulation separately by ethnic group for 1016 people. From the number of deaths observed in certain predetermined age intervals I constructed a life table. Both populations of females showed a statistically significant difference in the distribution of deaths (dx) between Caucasians and Native Americans (X2 df = 2, P < 0.05). These results concur with previous observations of other human populations. They are a result of both genetic and environmental factors such as hormonal differences, lifestyle, and access to medical care. For both Caucasian and Native American females, there was no difference in average age-specific mortality rates across the two populations (t Test df = 2, P > 0.05). Biological and evolutionary constraints on the human species may naturally limit increases in survivorship of human populations through time. Further studies involving fecundity and genetic variation in humans may provide stronger evidence for this hypothesis.