Survivorship Report

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Figure 1. Survivorship curves plotted on a log 10 scale of a cohort born before 1860 from the Millersville Mennonite Church, Millersville, PA. Survivorship between both females and males of the population dropped sharply between the first and second age class, then decreased slowly until reaching age class 80-89. The males of the population had a higher survivorship than the females over several age classes. Figure 2. The values of dx, the proportion of the cohort that died in each age class. There is a very high proportion that died from both sexes in age class 0-9, indicating high infant mortality. Thereafter, the proportions steadily decreased for the females as there were fewer individuals that remained alive. The proportion of males …show more content…

The population represented consists of wealthy, predominantly white, Mennonites of the area. Many life history characteristics are revealed through the data collected at the cemetery. For instance, the survivorship curves on a log 10 scale of the males and females of the population fit a type I survivorship curve. A type I survivorship curve indicates that individuals of the population experience high survival until later in life (Ricklefs & Relyea, 2014). Therefore, populations that fit a type I survivorship curve experience low mortality early in life then experience high mortality later in life (Ricklefs & Relyea, 2014). For this particular population, females and males experienced a sharp decline in survivorship when they reached 80-89 years of age. In addition, males tend to have a higher survivorship than females in several age classes, indicating females died at younger ages relative to males. In addition, Figure 2 shows that the highest proportion (about 33%) of the cohort that died for both females and males was in the age class 0-9 years. This reflects the high infant mortality of the time period, as few children made it to adulthood (Preston & Haines, 1991). About 13% of females died in the age class 10-19 compared to 6% of males. This reflects the how many women during this time period experienced high mortality due to complications with childbirth (Preston & Haines, 1991). Approximately 54% of females of the cohort died when they reached 20-29 years old, whereas 57% of males died by 30-39 years. Furthermore, Figure 3 reflects the difficulty the population faced surviving childhood and how the intensity of mortality increased as the population reached age class

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