Cemetery Demography Lab
Adapted from William Molnar and Nacy Flood
INTRODUCTION
As the United States has progressed through the industrial revolution over the last 150+ years, changes in the life styles of
citizens have been reflected in their age at death. Factors such as diseases and accidents have changed in their relative
impacts. One way to study these changes in human demographic patterns is to visit a local cemetery and collect data
recorded on tombstones.
By collecting information on the year of death for all individuals of the same age class (dying before 1930 or after 1931 a
certain time period) you can produce a graphical representation of their survivorship.
For the numerous species studied, the graphed curves usually fit one of three general shapes (Figure 1). Human
survivorship typically fits a type 1 curve. Especially interesting through is that slight, but distinct, differences can be seen
when curves from separate communities are compared, or when cohorts (groups of people) from different decades for a
single community are compared, as you will do during this lab.
Figure 1. Three types of survivorship curves:
Type 1 shows low initial mortality and many
individuals living to old age. Type 2 shows a
steady death rate. Type 3 shows high initial
mortality with few individuals living to old age.
Figure 2. Survivorship curves for the
decades of the 1830’s and 1880’s in
Newberry, South Carolina.
LABORATORY OBJECTIVES
1. Compare and explain the differences in the survivorship curves for at least two cohorts in a community with respect to
local or national history.
2. Speculate on future changes in demography, based on current community changes.
3. Collect age data and calculate survivorship for at least two cohorts in a community. Graph these data to show a
survivorship curve for each decade you studied.
MATERIALS AND METHODS
1. Data Sheets
2. The data needed for this lab will be collected virtually on Findagrave.com today in class or you can go on a personal
grave‐seeking mission this weekend for extra credit. 1pt extra up to 5pts for every tombstone you photograph and use in
your data set.
http://www.findagrave.com/cgi-bin/fg.cgi?page=gsr&GScid=7896
3. Above you will find the link to the findagrave website that lists graves at The Chapel of the Chimes gravesite right hear
near us! You need to find 100 people (50 male and 50 female) that died before 1930 (or a decade of your choice,
remember that older is better). It’s a random crapshoot, but with 1,911 to choose from you should find good data in short
order. Maybe you’ll run across a name that is familiar to you.
a. EXTRA CREDIT SIDE NOTE: Please be respectful of the deceased, as you are there as researchers, a representative
of this class and an upstanding young adult and future leader of this community. To prove you were at the cemetery you
need to take photos of the headstones you recorded using your cell phone or a camera.
4. Record birth year and death year for each individual in Table 1a & 1b.
DATA ANALYSIS
1. For each individual calculate the age at death (Table 1).
2. Summarize the data you collected into Table 2 (you should make 2 tables, one for males and one for females). Note that
data are clustered into age classes (first column) of ten year intervals. For the 0‐9 age class, count all of the individuals
which died at an age of 9 or less. Continue to record the number of deaths for each of the age classes.
3. The number of deaths for an age class is commonly abbreviated as "dx". When you reach the bottom of the column,
determine the total number of deaths and record this number in the indicated space. This number should equal the total
number of tombstones you counted for that period of time.
4. The third column is for survivorship data (nx) and the calculations of these data are cumulative.
a. Begin by placing a zero (0) in the lowest box of the column. To determine the number for the next box up add to the
zero the number for the number of deaths (dx) that appears in the column to the left and one row up.
b. Continue this process of adding on the number to the left and one row up to determine the data for each row of the
survivorship column. When you reach the top you should have the total number of tombstones that you originally counted
(50). (See Table 3 for an example of data determined in this manner.)
5. The fourth column calculates the proportion of surviving population.
6. Standardize the survivorship data to per 1000 (S1000) to allow you to compare data from the two time periods. Use the
equation below to make the necessary calculations.
S1000 = (lx) X 1000 Remember, lx = nx/total deaths
To check your calculations, the top line should be 1000 and the bottom line zero.
7. To standardize your data for graphing, calculate the logarithm to the base ten (10) of each number in the "survivorship
per 1000" column. Once again to check your calculations, the number in the top row should be
3 and bottom line will produce an error (log 0 is undefined) on your calculator. For this number just put "0".
8. Graph curves for both males and females.
ANALYSIS QUESTIONS
1. Compare the survivorship curves for males against those for females.
a. Explain the differences and why they occur.
b. Give details of possible biological and social/historical causes. For example, evolutionary theory
implies that females in the child-bearing years suffer higher mortality from childbirth deaths.
c. Describe changes in mortality for males as a result of wars.
2. Analyze and compare the mortality rates for the older age groups.
a. In general, why should these rates be higher than the average?
b. Predict how a nineteenth-century population would differ from the survivershop curve you made in
three ways.
3.
a. How would the survivorship curves of a developed country compare to those of a less developed
one?
b. How could survivorship curves be used to make judgments about environmental and health
conditions in different countries?
c. If AIDS continues to spread and no cure is found what would survivorship curves look like?