Population

Concerning Population

Since the first agricultural revolution in around 10000 B.C.E., the number of homo sapiens on the Earth has grown exponentially. This topic contains numerous branches and topics in and of themselves. However, it is next to impossible to know all there is to know about population. Some of the basic things concerning population are the crude birth rate and death rate, population pyramids, Zero Population Growth laws, population growth theories of Malthus, Marx, and Boserup, the Demographic Transition Model, the effect of resources and wealth on the population, population density, and which countries have the most people.

Understanding population density is a key part of learning about population. Population density is the measurement of population per unit of something. When measuring human population, the kilometer or the mile is used. Countries such as Indonesia, India, and the Japan have high population density. Indonesia has a population density of 326.51 people per square mile, India has 851.04, and Japan has 873.42. The five countries with the largest population are China, India, the United States of America, Indonesia, and Brazil, in that order. There are about 6.7 billion people on the earth. Those five countries make up more than half of the global population. (3,119,995,960 people) China and India make up about one third of the global population.

There are several theories on how population grows, and why it grows the way it does. One of the more prominent theories was coined by a man called Thomas Malthus. Malthus said that the Earth has a specific limit on how many people can be on it at once. This is known as carrying capacity. Once the number of people on the Earth goes over that capacity, there will not be enough resources to go around. When this happens, there will be checks on the population. Checks on the population are ways to decrease it if it gets too high. A positive check is when humans decide to lower the population by means such as contraception and celibacy. Negative checks are when the population is lowered naturally by means of disease, famine, drought, or any or all of the aforementioned. Another negative check is war. An additional theory was conceived by a man called Karl Marx. He said that population size is not the problem. He said that there is plenty of resources to sustain the people on the planet, but those resources weren’t distributed evenly, thus causing many people to starve. Yet another theory was formed by a woman by the name of Ester Boserup. She believed that the population would decrease if the number of subsistence farmers was increased. Subsistence farmers are people who only eat what they grow. They tend to be at or below starvation level. They tend to have many children because they need help working the farm.
Countries throughout the globe are at different stages in development. There is a way to tell what stage they are at now and what stage they will go to next. This method is called the Demographic Transition Model. The Demographic Transition Model is based on what Great Britain’s population did from before the industrial revolution onward. The model has four stages. Stage one is the pre-industrial stage of a country. This means that many people are farmers. The Crude Birth Rate is high. The Crude Birth Rate (CBR) is the measure of births per 1000 people. The reason that the CBR is high during stage one is because all of the farmers must have numerous children in order to have enough help on the farm and keep the family alive. The Crude Death Rate (number of deaths per 1000 people) is high as well, due to poor hygiene. In stage two, conditions start to improve. Sanitation is better, as well as medical technology. The CBR stays high due to tradition, and the CDR drops. Stage three is when the CBR and CDR both level off at a low rate. Sanitation and medicine improves even more. Stage four is the final stage of the model. In stage four, the Crude Birth Rate and Crude Death Rate go even lower. Sanitation and medicine are excellent, and most people have a good amount of money. There are critics of the Demographic Transition Model, however. These people argue that four stages is not enough. They say that Japan is already in stage five, which is theoretically when the CBR is lower than the CDR.

The age-sex structure is how many males and females there are in a country and what age those people are. The chart we use to show this data is called an age-sex pyramid. An age-sex pyramid is a chart that has the population numbers on the x-axis and the ages of the people in the country on the y-axis. There are bars jutting out from the age numbers on the x-axis according to the population of each age group. To keep the population under control, some countries issue a one child per couple law. China was the first to do so. The Chinese government wanted the population to stop growing. Although it slowed, the population did not stop growing. The reason this happened is because people were dying at slower rates, and there were many youth entering their reproductive years. This phenomenon is called hidden momentum. Many countries strive to reach Zero Population Growth, (ZPG) which is when the number of births is even with the number of deaths. To do this, the countries must impose strict population laws such as the one child per couple law. Occurrences such as hidden momentum make zero population growth hard to attain.

The number of people on the planet is growing at an astronomical rate. By 2050, the population is projected to surpass nine billion people. Will that number be carrying capacity? Is the Earth at carrying capacity right now? No one knows for sure, but it sure will be interesting to find out. Once the world does reach carrying capacity, there will almost certainly be wars over food, water and land. On the bright side, humans only live on about five percent of the earth’s surface. Humans did not become the dominant species by being dumb. They think, and if something does not suit them, they change it. Humans will adapt to living in places previously thought uninhabitable. They will figure out better ways to grow food. Nobody really knows precisely what the population will do. However, people will continue to populate the Earth regardless of what the experts that try to predict population patterns say.