BC1002 Module 3, Labs 2 and 3 Spring Semester 2004
19th Century Human Demography in New York City
Learning Objectives
· Learn to use birth and death dates to estimate age-specific cumulative survivorship rates.
· Learn to graph age-specific cumulative survivorship rates.
· Be able to compare graphs of age-specific cumulative survivorship, and be able to interpret and speculate about causes for differences.
· Become familiar with how life expectancy, rates of infant mortality, and other demographic statistics depend not only on biology but also on social factors (new technologies, urbanism vs. ruralism, wealth vs. poverty, etc.)
· Become familiar with how human demographic data, including data from a cemetery, may be easily biased.
DRESS APPROPRIATELY FOR THE FIRST WEEK OF THIS LAB (April 5-9): The first week we will be going on a field trip, RAIN or SHINE! You will be walking in Trinity Church Cemetery, a gorgeous old cemetery that overlooks the Hudson River from a steep hill. Because the hill is steep and the walkways are old, it is very important that you wear good walking shoes – sturdy sneakers or boots are highly recommended. You will be very uncomfortable and may even injure yourself if you wear heels, platforms, sandals, etc. Also, pay attention to the day’s weather report and dress appropriately. Be prepared for a change in weather by bringing a jacket, raincoat, umbrella, etc.
BRING A $4.00 METROCARD SO YOU CAN RIDE THE SUBWAY to get to the field trip site during the first week! Trinity Church Cemetery is located at 155th Street and Broadway. You will travel via the #1 subway. BEFORE coming to lab, Metrocard with $4.00 in subway fare. Please! This is important. Don’t hold up your entire class waiting in line at the fare booth or Metrocard machine. And avoid having to walk all the way back to campus from 157th Street.
BRING IDENTIFICATION FOR WEEK ONE. You will not be permitted into the cemetery without it.
Lab Overview: This is a two-week lab.
Week One: Please note that this is a tight schedule! Work and travel quickly to be sure that you have time to collect all your data and to return to campus within the three hours allotted for your lab.
· First 10 minutes: quiz and preparation for field trip.
· Next 45 minutes: travel to Trinity Church Cemetery via #1 Subway (157th Street stop).
· Next 15 minutes: walk to from subway to cemetery and brief orientation by instructor.
· Next 60 minutes: collect data for your decades; you must gather 100 birth/death data points.
· Next 45 minutes: walk back to subway and return to campus.
Week Two
First Hour: Analyze with your Trinity Church Cemetery data
Second Hour: Analyze data from elsewhere. Your instructor will provide you with a data set from another geographic location but from the same decade as your Trinity Church Cemetery data. These data were collected by students at other college campuses.
Third Hour: Each pair of students will be asked to spend 4-5 minutes presenting their survivorship curves from Trinity Church Cemetery in New York and from a cemetery in another, more rural geographic location.
Introduction
The study of human population biology is quite different from the study of animal or plant populations. In particular, it can be quite challenging to find data useful for studying animal or plant populations that exist in the past. For humans, it is relatively easy to gather information about human populations that existed in the recent past. One thing that the human species have done quite well for many centuries is to keep records of births and deaths.
Consider, for example, the obituaries of the New York Times. If you looked through them for two entire decades, you could get information about the age at death for many people, as well as information about their families, their occupations, etc. We would gather a very massive data set, and we might be able to use it to answer various questions. Do married men live longer than single men? Do musicians tend to die younger than bankers? Do women live longer than men?
Another example would be records of birth dates and death dates found on cemetery tombstones. We might look at tombstones from the 1800s and ask whether, in the past, deaths occurred earlier. (Why would this be? Think back to Module Two.)
In this two-week lab, we will spend one week visiting a cemetery to gather data about birth dates and death dates of New Yorkers. We will spend a second week summarizing and analyzing the data and comparing it to data collected in cemeteries at other locations in the U.S.
Week One: Our “Field Trip”
You and your instructor will travel by subway to visit Trinity Church Cemetery at 155th Street and Broadway. Incidentally, this is a unique site in all of Manhattan, because it is the borough’s only remaining active cemetery. It is affiliated with Trinity Church on Broadway at Wall Street. The original Trinity Church burial ground downtown is small and includes the graves of famous New Yorkers such as Alexander Hamilton. It’s worth a visit if you’re visiting the financial district as a tourist. In the mid-1800s, the church started a new cemetery on land that was once the farm of John James Audubon, the famous painter and naturalist. This “new” cemetery is now an extremely historic and beautiful site, filled with 100-year-old trees and overlooking Riverside Park and the Hudson River. Among many other wealthy New Yorkers buried there, you may notice the graves of Audubon, John Jacob Astor, and Clement Clark Moore, author of “A Visit from St. Nicholas.” [‘Twas the night before Christmas...]
Please see the front page of this handout for practical reminders about preparing for this trip.
Week Two: Summarizing Data and Plotting Survivorship Curves
The lectures in this class will introduce you to an important type of graph, a survivorship curve. A survivorship curve summarizes information about the typical ages at which members of a population die. An example that uses data from a cemetery in rural Pennsylvania is shown below.[1]
This graph permits comparing deaths that occurred before 1950 (circles) with deaths that occurred after 1950 (triangles). You can see that something has definitely changed in the population, because the shapes of the curves are different. This may reflect many of the medical and technological changes that occurred during the middle of the 20th century. What are some examples? Interestingly, if you focus on just the late 20th century curves (triangles) and compare men (open triangles) with women (closed triangles), there appears to be something different between male and female survivorship. What might this reflect?
At first, you may find it challenging to read and interpret this type of graph. By learning to construct these graphs during week two of lab, you should be able to meet that challenge more easily by the end of Module Three.
Week One: Field Trip Directions
DRESS APPROPRIATELY FOR WEEK ONE: The first week we will be going out in the field, RAIN or SHINE! You will be walking in a gorgeous old cemetery that overlooks the Hudson River from a steep hill. Because the hill is steep and the walkways are old, it is very important that you wear good walking shoes – sturdy sneakers or boots are highly recommended. You will be very uncomfortable and perhaps in danger if you wear heels, platforms, sandals, etc. Also, pay attention to the day’s weather report and dress appropriately. Be prepared for a change in weather by bringing a jacket, raincoat, umbrella, etc. Also be sure to bring your college ID card or you will not be permitted to enter the cemetery. No photographs will be permitted on cemetery grounds.
You will be assigned a lab partner and a 20-year period during the 19th century (1800s). When you are at the cemetery, you will need to walk throughout the cemetery looking for tombstones with birth dates that occur during your assigned 20-year period. You and your partner are responsible for gathering at least 100 birth dates and associated death dates. If you can get more, definitely do so. It will improve your graphs. You and your partner will be required to initial and turn in your data sheets in addition to turning in your individual lab reports. If you have fewer than 100 birth dates and death dates, you may lose points on your lab report. Work quickly!
Hints:
· Watch your step! There are loose stones, sticks, nuts, uneven walkways, etc.
· Have one person read stones and the other record data (bring a clipboard if you have one).
· Familiarize yourself with the data sheet format before lab.
· Record just the birth dates and death dates. Do the subtraction later.
· Sometimes only death dates and age at death are on a stone. You should be able to use such data. You just need to subtract the age from the death date to determine the birth date, and then check to see if the birth date falls into your 20-year period.
· Multiple birth and death dates on a single headstone. Look on all sides of a stone.
· Limestone (whitish) tombstones are often difficult to read because the rock has been damaged by acid rain. It may be best to skip these. There are plenty of legible headstones.
· In our lab, we are not focusing on differences between males and females. Recording this information is entirely optional. If you are worried about getting 100 data points, it’s probably best to skip it.
· If you are assigned a 20-year period very early in the 1800s, you may want to start at the top of the hill, close to Broadway. This is the oldest part of the cemetery.
· If you are assigned a 20-year period very late in the 1800s, you may want to stay closer to the bottom of the hill, near Riverside Drive. You may also use dates on the small crypt and mausoleum stones nearest to the bottom of the hill near Riverside Drive.
· Some old headstones are in Dutch or German but you should be able to figure out birth and death dates. Deaths happen after births.
Data Table 1: Collect at least 100 data points. Space for additional data is provided, because more data are better. For this lab, it is not necessary to record M or F, but a space is provided if you choose to do so.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
death year / birth year / age at death (death yr-birth yr) / male or female?
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
death year / birth year / age at death (death yr-birth yr) / male or female?
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
death year / birth year / age at death (death yr-birth yr) / male or female?
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
death year / birth year / age at death (death yr-birth yr) / male or female?
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
Week Two: Data Summary, Analysis and Interpretation
The first thing that you’ll need to do is to tally how many of your records (birth/death dates) fall into each age class. On the table on the following page, each row of the table can be used for each class, defined in ten-year intervals (0-9 years, 10-19 years, etc.) Table A below provides an example. It is based on data from the 1830s collected in Newberry, South Carolina. In Table 2, there is space for you to summarize your own data in a similar manner.
Explanations and Hints:
· The first column on the left gives each of the 10-year age classes, going up to 110+.
· The second column provides space to tally the number of deaths in each age class, which comes from working systematically through the data collected in the cemetery using Table 1.
· The third column provides space to write the total number of deaths in each age class. When filling in this information for your data in Table 2, work by columns. That is, fill in this entire column before trying to fill in the fourth and fifth columns for each row.
· Column four provides a place to put the cumulative number of individuals surviving to each of the age classes. Fill in this column starting from the bottom. In the example, you can see that the last row (Age class 110+) has a zero for this column. No one survived to be older than 110. Working up to the next-to-last row (age class 100-109), only one individual survived to be older than 100. Working up again, to age class 90-99, that one individual plus an additional four individuals survived to be at least 90 years old (i.e., a total of 5). For the age class 80-89, an additional 22 survived, which must be added to the 5 who survived to the even older age classes (22 + 5 = 27). Working up the column, this procedure continues. Since all individuals survive to the youngest age class (starting at age 0), that row gives the total number of birth/death records collected (From Newberry, SC, 160 individuals.) When working with your own data, double check this with the number of birth/death records that you recorded at the cemetery using Table 1.