We would like to take this opportunity to once again thank Dr. Merli on her presentation and for giving us so much material to discuss! we wanted to recap on some key points drawn from the lecture.
History of population:
Dr. Merli presented an intriguing overview of demographics and its methodologies. She began her lecture with a historical overview of population growth. Since the emergence of organized societies, population growth has been tremendously slow. It was practically stationary until the mid-18th century. Once the industrial revolution began, population growth exploded exponentially. The population that had barely reached 1 billion people in 1750 has now grown to over 6 billion and is predicted to reach 9 billion in 2050 according to median UN estimates.
The demographic transition refers to the cycle of birth and death rates that has occurred or is occurring in every society of the world. There are four stages. The first stage is high birth rates and mortality rates where the population has very little growth. This is the pre-industrial phase seen in Europe prior to the industrial.
In the second stage of the transition, mortality rates fall tremendously while fertility rates still remain high. These longer life spans can be attributed to better food supply and health care access.. This leads to tremendous population growth. Historically, this is observed in Europe and Western society during the early phases of the industrial revolution.
In the third stage of the demographic transition, mortality rates continue to fall while fertility rates also begin to decline. This is typically due to better education and economic opportunities for women, contraception access, and urbanization. Consequently, the population growth begins to level and is no longer rising as exponentially. This is seen in Western society in the later parts of the industrial revolution. Most of the developing world currently finds itself in this stage or in the second stage which explains their extraordinary population growth.
In the fourth stage of the demographic transition, both the mortality rates and birth rates are extremely low. Consequently, this leads to a steady, unchanging population. The US is an example of this. In some countries, the fertility rates can drop below the mortality rates leading to a declining population. This is currently observed in places like Italy and Japan. It should be important to note that these changes do not account for out migration or in migration and that those affect population changes as well.
Professor Merli’s expertise is on China’s implementation of public policy on fertility. In the 1960’s, the fertility rate in China was extremely high and averaged almost 6 children per women. Consequently, in the 1970’s, China initiated the “Later, Longer, Fewer” campaign to encourage the Chinese population to space out their births and have less children. The fertility rate sharply declined throughout the 1970’s to about 3 children per women. However, the “later, longer, fewer” campaign ultimately culminated in the “one-child policy” initiated in 1979. This restricts urban couples to only one child. As a result of this fertility control policy, the total fertility rate in present day China has fallen to 1.58. Since this is less than 2, this means the population is below replacement. *Replacement refers to the number of births required to “replace” the population. In basic terms for every couple that procreates, it would take two children to replace them. In reality replacement level is actually 2.1 instead of 2, as one needs to account for mortality.
The Future and Africa:
Interestingly, as population growth in Asia have begun to decline, growth in Africa has continued to grow exponentially. The African population has doubled since 1982. It is expected to rise to almost 4 billion by the end of the century. Nigeria is expected to be one of the most populated countries in the world. Thinking back to the demographic transition, Africa has experienced an increase in life expectancy and thus the mortality has declined. As with every country in the third stage of demographic transition, the fertility falls after the mortality does. Africa is currently in this stage.
The class ended with an enthusiastic discussion on the impact of high populations with respect to resources. Some were saying that population growth really doesn’t matter as much as the allocation of resources within the world. However, others emphasized that the population growth itself and the high volume of people will have the biggest burden. What does everyone think?
Cant wait for a rowdy discussion!
Christina Chao and Ryan Lion