Overpopulation refers to the planet having too many people for it to sustain. The worlds population is estimated at being around the 7.5 billion mark (May 2017) and is increasing all the time Ref: World o Meters . As you can see from the link previous, the numbers of people being born is over double the number of people that are dying.
The below is a simplified past and predicted future growith of the human population. No one can be sure of the exact numbers for each year, they are only estimates. The reference for this site is Ref: Livescience
|8,000 B.C.||5 Million|
|500 B.C.||100 Million|
|500 - 600 A.D.||200 Million|
|1250 A.D.||400 - 416 Million|
It depend son who you asked as to who you ask. Some people will say it will never be overpopulated, others will say it is overpopulated already. Some places are more overpopulated with higher people density than elsewhere.
By looking down on the planet at night, you can get an idea of the how widespread and populous the planet is by looking at the light population. In the picture below, you can see that the United States is heavily populated on the east coast and so too is the whole of Europe. The sparsely populated areas are where don't have access to have lights or the area is inhospitable. Its not a case of moving into the not so populated areas such as Africa because for example, the land at the top is desert and whilst some nomads live there, its not suitable for all. The below picture was taken by National Aeronautics and Aerospace Administration Ref: N.A.S.A. . Since that time, the light would have increased as the population has increased and the map might look a little but not much different to it does now
Thousands of years ago, the worlds population hardly took off, it stayed static for thousands of years. What the key was the creation of farming. The earliest records of farming date from about 5,000 B.C. when crops were first grown which matches up with the first item in the table above. Ref: Local Histories Since farming, the world population has increased steadily until the mid-late nineteenth century. The worlds health and wealth has also been a contributing factor.
Population Control is a highly contentious issue. Having babies is considered a human right and no one should tell you how many you can and can't have. An international conference was called and it was agreed that countries would work towards slowing the increase.
China has been active in population control, although its method have not welcomed. China has used the carrot, i.e. given benefits to those with one child and disgracefully the stick, enforced abortions and sterilisations. Chairman Mao actively encouraged increasing the population with his view that if you increased population, you increased productivity . Over time this proved wrong and China reversed this policy to one child families. They actively encourage one child families but this has caused a gender imbalance. The ratio of boys to girls in China is 116.9 in 2000. The Government has reacted to this by allowing families to have a second child if the first one is a girl but that will not resolve the situation. Some families in China are taking drugs so that they can have a multiple birth thus getting round the Chinese law. Ref: Dontow
Nature's way of controlling the populations is through natural disasters and disease. However, humans are getting better at defeating Nature's population controls. One of the methods Nature uses is virus but as we expand our knowledge and intelligence, we defeating viruses. Already, we have beaten Smallpox, there has been no cases of smallpox since 1977 in Somalia Ref: W.H.O..
Polio is predicted to be the next disease to be wiped out, however, the virus is still prevalent in three areas of the world, Nigeria, Afghanistan and Pakistan, all area under control of insurgents. Since originally writing that statement, Nigeria has been taken off the list so only Afghanistan and Pakistan are remaining. Ref: W.H.O.
Now that we are able to find cures to diseases, nature's population control mechanism is not as effective as it used to be. New diseases are emerging all the time but as our knowledge of diseases grow, these will be defeated. Whilst old diseases are disappearing, new diseases are appearing, e..g Ebola and AIDS. As we move into new areas because of the need for land, we risk waking up and discovering diseases. A virus that was discovered frozen for 30,000 years was woken up by scientists to test if the virus could come back alive and they succeeded. Ref: B.B.C. .
Antiviral and Antibacterial drugs have a shelf-life because the diseases that they treat can can become drug resistant. Causes of drug resistance include inappropriate use such not completing the course or being used where not necessary. Antibacterial drugs are given out when the patient has no need but the patient demands it. It can be hard to persuade the patient that they don't need. Ref: Modern Medicine
In Sweden and Denmark, they have quite low use of antibiotics and low amount of antibiotic resistance compared to other countries in the world. In some countries, the antibiotics are used on animals in order to fatten them up and therefore increase the amount of food that the animal provides for them to sell. Ref: NPR
Drug companies such as Bristol-Myers and Eli Lilly left the antibiotics business because they are not cost-effective because those drugs take a long time to put into the market and have a relatively short lifespan so not much return. Drug companies are turning to conditions which will generate a constant financial pipeline, ones that will ensure a future money line. Fortunately, now, some companies as Glaxo and Roche are moving back into the field of antibiotics. Ref: Bloomberg
The last time a new group of antibiotics was created was in 1987 and since then, nothing has progressed. Since writing the original comment, Scientists have discovered a new possible antibiotic found in dirt where a lot of the worlds bacterias live. Ref: Science Daily
David Cameron, the British Prime Minister in 2014 asked Economist Jim O'Neill to investigate the situation of why drug companies are producing new antibacterials. Ref: AMR Review .
Some countries if it was not for immigration, their populations would be on the decrease. One country that has seen a big decline compared to other countries is Ukraine, it had been 52 million in 1993 to 45 million in 2013 when the populations of Crimea and the breakaway territories were included. Ref: Newsweek.
Other countries that are seeing decreasing populations are as a result of migration for work or in the case of Syria, war. To offset emigration, some countries, are importing migrants to replace those that have left.
With overpopulation comes a range of issues that's need to be addressed. The list has come from Everything Connects which goes into detail on each of these subheadings.
One of the arguments against overpopulation to say that Earth could support a large expansion of population is that we could all live in Texas without any problems. Ref: Overpopulation is a Myth .
The problem with that argument based on how much space a person needs doesn't take in account how much land is needed to grow food or streets or places to work. The amount of land that is needed to grown enough grain and other ingredients for a loaf of bread is you would need to plant roughly 9 square feet.
To sustain us, we need resources such as food where we need large amounts of space to grow foods. We need energy which at the moment, most of the energy we produce is from burning fossil fuels such as coal, oil and gas. The problem with fossil fuels are that they're dirty and that they pollute the environment and also that is a finite amount of fossils. Once the fossils are all used up, there not coming back, well, not for millions of years. Atomic power is cleaner but the waste that is produced has to be stored somewhere which you don't get with Fossil fuels because all fossil fuel waste is gas such as carbon dioxide and that all goes into the atmosphere.
Clean energy production such as Wind, Solar and Water are the future because they can never run out, these power generators will always be on (ok, solar won't generate in dark). There is resistance to Wind Generators as they are ugly on the environment but they don't produce the same amount of waste unlike the other types tho. There are lots of campaigns to get rid of Wind Farms. The B.B.C. have produced a web page where they have estimated when the worlds fossil fuels will run out. To find out when the fuel will run out, search for 'Fuel Gauge' on the page. In short, it estimates that we have 53 years left of Oil, 54 for Coal and 112 left years for Gas. Just because the resources are going to be there for the next fifty years or so, we should be weaning ourselves off the resources now. Coming off the addiction of fossil fuels can help slow down Global Warming.
Many science fiction writers write about how the population will explode and cause wars. The film Logan's Run starring Michael York and Jenny Agutter was set in the future. Humans had built huge dome cities where they live because the world outside had been destroyed through wars and overpopulation. Inside the dome, when people reach thirty, they need renewal but in fact, these people are simply killed to keep the population down. Other storylines talk about overpopulation causing wars, reduced energy supplies and lack of food. The 'Mad Max' films are set in future apocalyptic world where the situation mentioned has occurred.
Other writers talk about relocating people to other planets so that planets don't become overpopulated. Peter F. Hamiltons' Commonwealth timeline books are set in a future universe where humans create portals to other worlds so that they can inhabit them. People also don't die, they regenerate without the possibility of dying as in Logan's Run.
Whilst being able to expand onto other planets would be great. The reality is that we are moving more towards a 'Mad Max' style future. Scientists are not yet able to create portals or space ships to be able to transport us to a new planet.
In Inferno, the film of the Dan Brown book, the antagonist Bertrand Zobrist, a brilliant scientist has created a virus to wipe out half the worlds population. In the book, its different because the virus makes half the worlds population sterile.