Science 1102 (Hoban)

A. Population growth over time

* In the past population growth was a universally regarded as a good thing. For parents, high birth rate meant more children to support them in old age; and for society, it meant a greater pool of labor for factory work.

* As population continues to increase, it is becoming more of a problem rather than the good thing it once was. This continuation of increasing birth rates as said by Thomas Malthus that if society didn’t start cutting back on population growth then it would continue to grow to the point that it outgrows the food supplies.

* Although population growth has slowed over the years, it still continues to grow. Countries, which are more poverty stricken, tend to have higher birth rates. People in countries like these have a low accessibility rate to contraceptives and birth control. But countries that are more industrialized tend to have lower birth rates. This is because women have become more educated about birth control. Government in some places have limited the number of kids couples are allowed to have while other governments have set up family planning plans and even offer incentives for couples to have a certain amount of kids.

* Populations continue to increase and that is because of the lack of knowledge that some countries have compared to others.

B. Population doubling times

* To determine when a population will double: take the growth rate of that population and divide that into 70 to find out the number of years it will take for that population to double

* 70/ (growth rate) = # of years it takes population to double

C. Limits of Growth

* Malthus

* Thomas Malthus (1766-1834): an economist, who argued that unless population growth were controlled by laws or other social structures, the number of people would eventually outgrow the available food supply.

* “An Essay on the Principle of Population” (most influential work; published in 1798)...