Human Population Growth: Will Anything Stop It?
Since the industrial revolution, the population of humans on Earth has been growing exponentially. As we have been learning, exponential growth cannot continue forever. There will always be limiting factors that will stall the growth of any population. What could those limiting factors be for humans? Will we ever experience them?
How has human population size changed over time?
As can be seen in the graph, human population grew relatively slowly for thousands of years. Certain historical events had major impacts on population growth such as the development of agriculture, plowing and irrigation methods being developed, and the affects of the Bubonic plague. It wasn't until 1804, after the start of the industrial revolution the human population first reach 1 billion. Ever since, human population has been growing exponentially thanks to the development of medical technology.
Why do population growth rates differ among countries?
Demography is the study of human populations and examines characteristics of human populations and attempts to explain how those populations will change over time. Birthrates, death rates and the age structure of a population help predict why some countries have high growth rates while other countries grow more slowly. Throughout history, the birthrate and death rate was relatively the same throughout the world. Over the past century, many developed countries experienced a demographic transition, meaning that the high birthrates and death rates that these countries experienced in the past have changed over time so the the birthrates and death rates are much lower now.
It is predicted that once all countries experience their demographic transition, global human population will reach a carrying capacity and that the growth curve will represent logistic growth.