- Education and Science
World Population Growth through Time
The current world population is more than 7 billion and will continue to grow in the years to come. It took about 250,000 years as modern humans and about 6 million years from the time when early hominids first appeared in the world to reach this number. During this period the human population has not always been in an upward trend on its way to the 7 billion mark. Some dips in the population progression occurred from time to time cause by major natural or social events that slowed it down. At one point along the way man almost joined the club of extinct animals but somehow managed to beat the odds to continue its existence today. The downside to this phenomenal population growth is that it is putting an ever increasing pressure on the world ecological system as it continue to grow.
In the Beginning...
I am not going to look at the starting point of our population from a religious perspective, but obviously somewhere along the way our population began growing from a group of humans living in the Great Rift Valley in eastern Africa as indicated by all the hominid fossils found there over the years by many anthropologists. At the time this part of Africa was the only place in the world where early humans were living. Early humans populated other parts of the world later after several waves of migration from Africa.
Of course no one at the time in the early human groups kept track of the population but we know it took more than two individuals to get the human population going. Humans gradually appeared on earth through millions of years of evolution from earlier primate ancestors based on fossil records found in Africa. So based on these evidence It is reasonable to assume that there were not too many humans in the world at the time. Just a few scattered here and there around the Great Rift Valley in eastern Africa.
Life was short for early hominids. The typically life span of man back then was less than 30 years as compared to 75 years today. Many died from injuries, diseases and death caused by animal attacks and as a result the human population increased very slowly in the beginning.
We Almost Became Extinct Along the Way
Before our population went into high gear in the upward direction, mankind almost became extinct about 70,000 years ago due to changes in the global climate. At that time it was estimated that there were less than 25,000 humans in the world. This near extinction event reported in the Journal of Human Genetics was determine from data generated from genetic analysis of the mitochondrial DNA found in every living person in the world. This DNA is passed down from the mother to her descendants and can be traced to one woman who lived in African about 200,000 years ago. This DNA can also be used to determined if someone is genetically related on the maternal side of the family.
During this time Earth was undergoing another glacial period that caused a cool, dry environment to develop in southern and eastern Africa thus forcing the small groups of humans to scattered. These droughts lasted for thousands of years at times based on geological evidence. What saved us? Our carnivorous diet and our use of fire. As a result of these activities the dwindling population of mankind took an upward direction again toward the first million.
Population of Earth Reaches One Million People
According to historical records, it is estimated the world population did not reached the first 1 million until around 10,000 BC, roughly 250,000 years after modern man first appeared. Most of the population was centered in the region of China and other areas in the Asia region of the ancient world. It would take another 5,000 years before the population would reach the 5 million mark and would be less than 150 millions humans in the entire world by 1 A.D. as indicated in John H. Tenton's "End of the Migration Epoch", printed in 1955 in The Social Contract.
The Bubonic Plague Hits the Human Population Hard
By the 1330s, growth of the human population took another downward turn because of natural and social events. The outbreak of the Bubonic Plague (or Black Death) in China dramatically affected population growth that will last for years after spreading by fleas from a port in Sicily, Italy in 1347 into the European countryside on its way to London. At the start of the outbreak the world population was estimated to be between 400 million and 500 million with 75 million estimated living in Europe. When the plague was over five years later 25 million people would perished from the disease causing a 33% percent drop in the European population and a 5% to 6% drop in the world population. For comparison, if this had happened today in the United States a 33% drop in population would be 99 million people. Here is another comparison to consider, a 5% drop in the world population would be 350 million people if the bubonic plague had struck with the same virulence today. That is a significant drop in population.
Population of Earth Reaches One Billion People
It would take almost another 500 years after the Bubonic Plague for the world population to hit the 1 billion mark and that milestone would not be reached until around the first decade of the 19th century. The 19th century was a very critical turning point in the world population growth. It was the century when antibiotics first appeared on the medical scene along with improvements in sanitation. These were the two major events that improved the quality and longevity of life in the developed countries. As a result, the birthrate went up dramatically while at the same time the death rate dropped causing a significant acceleration in the population growth rate. In Europe the population doubled from about 150 million to 291 million in that 100 years and during that same time period the population of London went from 1 million to 6.7 million making it the largest city in the world. Countries, such as North America and South America only had an estimated 16 million and 9 million people, respectively, at the beginning of the nineteenth century.
It is incredible to note that at the beginning of the 19th century China, the most populous country in the world today, only had a population estimated to be between 300 to 400 million people, but the population growth rate would increase rapidly by the mid 1900s. Today 19.2% of the world population or 1.4 billion people live here. India is the second most populous country with 17.4% of the world population with 1.2 billion people. The two regions combined contain 36% of the total world population. On the other end, Pitcairn Island, a group of small islands located in the southern Pacific has a population of only 50 people today and this country has it own flag despite its small population.
During the early 20th century the world population took a slight dip downward during the two World Wars. The world population went down by 8.5 million people killed in the war and 11 million people lost their lives in the concentration camps during the Holocaust. This was a decrease of about 1% of the total world population as a result of these major world events. It was a small drop in the world population but a large number in terms of the number of people killed. The world population has not drop by more than 1% since those historical events.
The Worldometer- Current population
Click on this link to see the current population:
Will the Population Growth Continue to Go Up?
The world population will continue to grow based on three projections in a 240 page report published in 2006 from the Department of Economic and Social Affairs in the Population Division of the United Nation organization entitled "World Population to 2300", but not at the current rate. It took 123 years from 1804 for the world population to reach the 2 billion mark and from that point on it would surpassed each billion at an ever accelerating rate. Today the growth rate is so fast that the world population took only eleven years to grow from 6 billion to 7 billion people and by 2050 the growth rate is expected to decline slightly due to mounting pressure on world resources as the number approaches the 9 billion mark based on medium projections published in the report. The report also stated that the world population probably will stay around the 9 billion mark and may decrease slightly until 2300. This appears to be the most likely outcome in the future.
However, high projection indicates the population could go as high as 36 billion by 2300 and a low projection indicates it could actually go down to about 2 billion people in that same time period. In both cases these are dire future projections. The first one seems to indicate over-population and the second one seems to be indicative of some serious future disaster will occur between now and 2300. Let us hope the world leaders are watching the population clock just as much as the rest of the world is to start serious planning to keep these two scenarios from happening. We might have to start devising plans for a Terra Nova in the distant future if they do not start paying attention pretty soon.
© 2011 Melvin Porter