Chapter 53, Problem 53.6CR

The human population is no longer growing exponentially but is still increasing rapidly (pp. 1205-1209)

• Since about 1650, the global human population has grown exponentially, but within the last 50 years, the rate of growth has fallen by half. Differences in age structure show that while some nations' populations are growing rapidly, those of others are stable or declining in size. Infant mortality rates and life expectancy at birth vary widely in different countries.

• Ecological footprint is the aggregate land and water area needed to produce all the resources a person or group of people consume and to absorb all of their waste. It is one measure of how close we are to the carrying capacity of Earth, which is uncertain. With a world population of more than 7.2 billion people, we are already using many resources in an unsustainable manner.

How do humans differ from other species in the ability to "clloose" a carrying capacity for their environment?