Discuss how human survivorship curves might have been different, say, in the Middle Ages when health care was minimal and many children died of the childhood diseases for which we are now immunized. Many women died giving birth, and infant mortality in general was considerably higher. Have the students direct as you draw a hypothetical survivorship curve for people 400 years ago. It should show a high juvenile mortality, then taper off to a sloping horizontal in the adult years. At the age of 50 or so, the line should again take a turn toward the X-axis as many older people die.
How is this different (or is it) from the survivorship curves for countries such as India or Ethiopia?
(See Leland G. Johnson, 1987, Biology, 2nd edition, Wm. C. Brown Publishers, Dubuque, IA, p. 848, for a comparison of survivorship curves in Sweden over a number of centuries.)
Most people agree that human population control works best when it is voluntary, rather than mandatory, and when parents choose to have fewer children. Explore this topic with your students. Ask them such questions as:
Are you willing to limit yourself to having two children or less during your lifetime? Why or why not?
If you want more children than two, are you willing to adopt? Why or why not?
Are you willing to have children later in life, which limits the number of generations in your family alive at one time? [Hint: Show students the mathematics of this very viable alternative. If two adults choose to have children at age 20, and their parents had them at age 20, and so on down the line--and if everyone lived to be 80 years old--how many people would be alive in one family made up of four to five generations? Compare this to having children at a later age, say 30-35, when three generations are alive at once.]
Last, emphasize the importance of family planning. This is important from many aspects (economic, health of the mother and her infant, and social--having both parents to raise the child).