What is the sustainable population?

Question

I hear a lot of people saying that we are beyond our sustainable limit for human population but I have never heard anyone say just what is the number of humans on
earth that would be "sustainable". I put that in quotes because I think that we can sustain probably more human life at the expense of another species. So I guess my real question is what is the number of humans that would be sustainable
not just for humans but for every species on the earth to flourish an evolve in their own natural way?

If we set this number out there it might help us to actually achieve it. What barriers exist towards education, policy making and proselytizing of religions that support the idea of having multiple children per married couple?

Answer 1

I read that is was 3 billion people, but i can't remember the source now. In 50 years at our current rate of growth, we'll be at 10 billion souls, with zero fossil fuels, zero coal and other natural resources. Wars will be fought over water.

Will technology save the day?.....maybe. Will we change our ways and avoid the impending train wreck?....doubtful. Will there be some cataclysmic event to bring us back to more sustainable levels?....probably.

Anyway, sleep tight....

Answer 2

that's a tough question that I will not even try to answer. instead, I will try to figure out what problems are relevant to the number.

1) War - waste of money, energy, and life, which could all be put toward more important things - money to education; lives to other jobs and volunteering; energy to anything else: just save it for later. Peace.

2) Agriculture - People eat McDonalds. I shouldn't have to say more than that, but I will. The Sun has got to be the best natural resource we have. If it dies, we die. Plants are our primary producers and should be more of a part of our diet than they currently are. As long as we can feed our population, it should be well sustained. Farm
If we stop eating unhealty, crappy food, everyone will be a lot better off. cut out the hormones and crap in our meats, the preservatives, the pesticides, the artificial colors (just because), etc.

3) Education - I can't remember hearing of a criminal (very many - I mean street criminals) who was both intelligent and mentally sound. We can fix the intelligence part to some extent; at least more than we currently are. That should cut down on crime and the cost of dealing with crime. Very low crime rates would be good for real estate - there wouldn't usually be a "bad part of town".

4) Housing - This one is mostly done already. The second thing we need to sustain our population is shelter.

5) Jobs - Workers support the economy - as much of a farce as it may be. If unemployment drops and wages balance so there are no poor or rich people (one class), ex-poor people will be able to support themselves and won't be an obstruction to overall sustainance.


but seriously, you'd have to look at the number of people vs. the number of jobs, homes, average food consumption per day, crop yield per acre x number of acres total, and meat consumption vs. animal growth time.

then if you want to stabilize it, you'd have to revolt against the government, create world peace, take control over all businesses, imprison, deport, or impound anyone who will not be fit for this sort of life, employ more forms of public transportation, and maybe convert all workplaces to a 24 hour schedule (4 shifts during which one quarter of the population will work) instead of this typical 9-5 thing.

otherwise, it will probably fluctuate at all times

Answer 3

Well it is "natural" for populations of species to go up and down over time. The classic case documented in various studies is the relative populations of rabbits and coyotes. If there are lots of rabbits, then more coyotes will be born until the population of the rabbits is decimated and then many of the coyotes die of hunger and the cycle begins again.

Maybe it is "natural" for the human population to grow dramatically more. I think you might be making an arbitrary judgement on what is natural. It apparently was "natural" for the dinosaurs to become extinct. The success of one species usually inhibits others.

Certainly the human species has had a giant impact on other species. We should take responsibility and care for our environment, and mark out protected habitat for other species to thrive in. But I think it is a mistake to pick a number out of the air and declare that is a "normal" human population.

The human population is certainly no where near what existing farmland will support. It is our distribution and political systems around the world (think Mogadishu) that is responsible for human hunger, not an actual food shortage.

Answer 4

There is nothing new with experts claiming the earth is overpopulated. If you believe Malthus, the earth should have been overrun with people 3 centuries ago. It appears that humans are resourceful and rational enough a species to manage land use enough to sustain a much larger global population than there is now. For instance, in the US alone, 75 percent of the land west of the Mississippi river is not inhabited at all. Certainly it is not economical to develop large chunks of sparsely inhabited states like Wyoming currently; but at a higher pop. level those trade offs may change.

Answer 5

There have been a couple of authors that wrote paperbacks on the subject, one was,"the late great planet Earth". It compared Earth to a spaceship that could grow a certain amount of food, create enough breathable air, etc. Personally I think we have way too many people on the planet and we are wrecking it at an ever increasing rate.Experiments done with lab animals have some interesting results, too many rats in a given area, their violence goes up fast! Does this ring any bells?

Answer 6

I don't think that this question has a simple one number answer. The answer depends on a number of factors. These include (not necessarily in order of importance):
1. Technology. Food yields are increasing due to higher yield crops and better techniques. Resources can be utilized without the major impact on the ecology as in the past.
2. World Political/Economic Structure.- Food goes to waste in parts of the world, and people starve in others. How well is the food that we have distributed?
3. Regional population growth- Parts of the world have population increases that far outpace their ability to provide food. The prevelance of this will affect the total.
4. Ecological Impact- How badly are we impacting the world's ecology with our building, food production, polution, and exploitation of the world's resources? The smaller the impact per person, the more people the world can sustain.
5. Regional/National tastes and desires- In the U.S., we eat a lot more meat than they do in other countries. Range animals consume more food than they produce. The more meat, the fewer people can be fed. In addition, most people in the U.S. and Canada eat more than necessary (and I am one of them). We also have large cars, and plenty of electronic devices. This means that the impact per person is much greater in the U.S. than in much of the world.

This is not an exaustive list, just a top of my head on a Saturday morning list. I also am not trying to place value judgements on any of the above cases. But, as I see it, all of the above factors affect the ability for us to sustain a population. I have read that 1 billion would be appropriate, but if we do things differently, we could sustain much more than that.

As for education and religious beliefs. In eduction, I assume that you mean educating the people as to the importance of sustaining a given number. This is very difficult. People, even if they know that a policy is for the best, will do what they consider best for themselves. Except for a small minority of individuals, people will only make sacrifices for the common good if the impact on them is minimal in time and money. Populations drop when it is no longer economically necessary or desirable to have a large family. If a large number of children is necessary to help earn money, or who are there to provide domestic help and old age security. In many cultures, a large family is a social statement of status. The ways that this changes is through economic growth. In countries where jobs became more prevalent and the standards of living increased, the birth rates dropped. They became too busy to raise large numbers of children, and the children's needs and wants became too expensive to provide for all. Cars, homes, electronics become the status symbols instead of more children- although we come full circle to the ecological impact of these products. Old age security is provided by the state and one's own savings and pension plans. Religion plays only a secondary role in this. Catholic and Muslim families shrink in size when the standard of living increases. Even Mormon families are smaller now than in the past. In just the last generation, the very large families of Cambodian and Hmong immigrants to the U.S. are shrinking. This is likely to be the case over time in most, if not all, regions.

Answer 7

The theory is more complex than that, with many variables. You need to look at the gestation period, the number of offspring in each litter, the infant mortality, the age to maturity, the lifespan, the ratio of male to female, the degree of monogamy, and other factors. Think about extreme examples; insects can have thousands of offspring in a period of weeks, with one male fertilizing any number of females, while an elephant may only have one or two over a period of decades, and is generally monogomous, with one male only fertilizing one female.

Answer 8

About 2 billion. I am all for negative population growth.

Answer 9

Egypt has 80 Million Citizen living in it!!!
That's our POPULATION....
Deal with that my Dear! LOL
That's all I have to say for ya.

Answer 10

maybe 6.5 billion is enough, beyond that we dont need pollution to change our climate our body heat temperature alone will make the globe warmer.