Biology 12

SKILL FOCUS

Predicting

Performing and recording

Analyzing and interpreting

Communicating results

Investigation 15•A

508 MHR • Unit 5 Population Dynamics

Pre-lab Questions

What is a population? Are its boundaries defined only

in space?

What data do you need to construct a survivorship

curve for a population?

Problem

Does survivorship change over time in human

populations?

Prediction

Make a prediction about how the survivorship curves for

past and present human populations might differ.

CAUTION: When exploring the cemetery, take care

not to disturb the landscape or injure yourself.

Materials

pencil appropriate footwear and

clipboard clothes (possibly including

field data sheet rain gear)

Procedure

1.Design a field data sheet to facilitate data collection.

The sheet should be standardized for all members

of your class and for all teams collecting data. It

should have columns or blanks in which you can

record gender, age at death, year of death, and, if

possible, the cause of death for each individual

studied.

2.Divide yourselves into groups and designate which

ones will collect data on certain segments of the

population. The data collected will depend partly

on the number of gravestones or death records

available and the age of your community. Ideally,

collect data on at least 200 individuals who died

during each of these three intervals: 1980 to 2000,

1930 to 1950, and 1880 to 1900. For each of these

intervals, have one group collect data on females,

while another group collects data on males. If your

opportunities for data collection are limited, a

division of deaths into two time intervals, pre- and

post-1950, will show some of the same patterns.

Ensure all team members are clear on their

respective roles regarding data collection before

proceeding to the cemetery.

3.Visit one or more local cemeteries (the older the

cemetery the better) and record the information

described in step 1. (If unable to visit a cemetery,

use the Web Link preceding this investigation to

gather your data.) Ensure that members of the same

group avoid collecting data on the same individual.

Behave in a way appropriate in cemeteries by not

stepping on burial plots. Data can also be obtained

(with permission) from death records, which may be

held at city hall or at a records office elsewhere in

your community. In some cases, death records for

individuals buried in a cemetery are kept in a central

office at the cemetery. In some ways, death records

are better to work with than gravestones; they are

not subject to weathering or the effects of acid

precipitation (which can make inscriptions impossible

to read). Also, the cause of death is regularly

recorded (it is seldom found on a gravestone).

4.Return to the lab and sort your data so you can

collate the numbers of individuals of each gender

in your time period who died during each of the

following age intervals: zero to just under five years

of age, five to just under 10, 10 to just under 15,

15 to just under 20 and so on, up to a final interval

of 95 years of age and over. Again, all groups

should use similar data sheets.

Cemetery Studies of Human Demography

Cultural changes often have profound effects on the birth and death rates of a

population. In this investigation, you will have an opportunity to collect (or use)

data to construct survivorship curves (Chapter 14, section 14.4) for two or more

human populations. You will also examine the process of demographic transition.