Talk:Population growth

About: Population growth rate & ratio

The formula makes no sense at all to me. Compare with this: $X=Y*100\%=Y*100/100=Y$

Am I wrong with this? If not, then the formula given in the article simply states that Population growth ratio is the same as its rate, which is certainly not the case. —Preceding unsigned comment added by 222.6.194.168 (talk) 13:05, 20 November 2009 (UTC)

What do you think it should be? Did you notice the next paragraph which I wrote over a year ago? For a sufficiently small time period, or small growth rate, it is close enough. Yours is the first comment related to the formula since I added the (sufficiently small time period) modification, and the following paragraph. Gah4 (talk) 05:19, 10 December 2009 (UTC)

Measuring growth

I added the word 'unit' to the first paragraph, but not (yet) to the equation. The equation as written is, in general, not correct. If the growth rate is measured as growth per year (as is usual), the time period in the equation given must be one year. Given: $P=Poe^{kt}$, and the population at two time points, $P$ and $Po$, $P/Po=e^{kt}$, $ln(P/Po)=kt$, and finally $k=ln(P/Po)/t$. For sufficiently small $kt$, the equation given near the top of the page is correct, but in general it is not. I am not ready to change it yet, anyone else want to comment? Gah4 (talk) 21:43, 11 June 2008 (UTC)

The equation is non-sense as it is now:

$\mathrm {Growth\ rate} ={\frac {(\mathrm {population\ at\ end\ of\ period} \ -\ \mathrm {population\ at\ beginning\ of\ period} )}{\mathrm {population\ at\ beginning\ of\ period} }}$.

The dimension of (per capita) growth rate should have time in the denominator, as it is a rate. According to the equation, growth rate is dimensionless. Better is

$\mathrm {Growth\ rate} ={\frac {\mathrm {population\ at\ end\ of\ period} \ -\ \mathrm {population\ at\ beginning\ of\ period} }{\mathrm {(population\ at\ beginning\ of\ period)\ x\ (length\ of\ period)} }}$

OpenScience (talk) 19:31, 19 January 2010 (UTC)

OT commentary

We supposedly ""Evolved"" around a 100 000 years ago ........... look at the graph and be logical . If we evolved 100 000 years ago our population would be absolutley ginormous . Working it back the human population has been growing only a few thousand years. Look at the graph or do the logarithmic calculations quickly (ok granted your calculations won't be perfect but they'll give you a ball park figure) Certianly doesn't look like a hundred thousand years to me. Rather supports a flood 4400 years ago. (Paladin)

I suppose so, but it is a big leap without any supporting evidence. A higher death rate in early populations would also account for the difference. There are many variables in the human growth curve to consider. Gah4 (talk) 16:04, 3 May 2008 (UTC)

....I was under the impression that Wikipedia was NOT the place for religious debates. While I am Christian myself, this is most certainly NOT the place to say that one does not believe in evolution and force your beliefs on others. Besides, it's perfectly possible to be Christian and believe in evolution. Oh, and, no, the population would NOT be "absolutely ginormous". It is only in recent years that we have been able to lower the death rate from fairly common diseases and, for the most part, eliminate epidemics of life-threatening sicknesses, oh, and we've learned quite a bit about nutrition. And consider the lives that wars have taken, too. Stars in the Night Sky 19:15, 15 April 2007 (UTC)

Hi , I was merley making a personal observation which as far as I understand im allowed to do (I wasn't under the impression that I have to believe in evolution to comment on wikipedia). Neither was I forcing my "beliefs" on anyone . As it happens im not even a "short day creationist" ! However looking at the evidence im beginning to lean that way . I also know you can be a Christian and believe in evolution , as I used to ! I used to go with theistic evolution however after looking at the arguments and looking at evolution I decided that it was fatally flawed, so I no longer believe in it . Also on the points you made the function is exponetial . Also I don't think they had such great sanitation or medical science 1000 years ago , however even looking at that graph, that is when it begins to rise rapidly. Granted it has sored in that last few years proably significantly because of the reasons you mentioned . However I feel the populaiton should atleast be significantly higher a long time before that point (its not even readable !) if homosapiens "emerged" 100 000 years ago (In my opinion). Look at rats etc. and how they multiply , we have a great advantage over them , in the fact that we are to perceive when we run out of food and space and can move. God bless you, Paladin 14:23, 17 April 2007 (UTC)

Article talk pages exist solely to disuss the article, not the topic. If you guys would like to discuss this topic there are numerous forums, chat rooms, and other venues. -Will Beback · † · 18:13, 17 April 2007 (UTC)

POPULATION GROWTH IS HOW FAST THE RATE OF THE PEOPLE IS GOING UP. IT IS VERY IMPORTANT BECAUSE THATS HOW OUR NUMBERS MULTIPLY AND HOW WE KEEP THE COUNT IF EVERYONE.

Uh, aren't the rate of population growth and the population growth rate very different things? One is a derivative of the other, right?

Future World Population

world population get? How will the transition from current rapid growth phase to a sustainable stable phase occur? Will this be an easy or difficult transition? -- Huysmantalk| contribs 22:02, 4 June 2006 (UTC)

Unnecessary citation request

The citation request on this assertion: "It has been proposed by many that population growth, if not controlled, could lead to a situation where demands for resources outstrip their ready availability (i.e., overpopulation).[citation needed]"
is unneeded. It's completely obvious after a moment's thought. In fact, the original statement is too timid. If you have 500 people a day crowded around a well that can supply water for 200 people a day, you've got a problem. This is not a theory, it's simple common sense. So, rather than a citation, the article should be expanded to include a little basic logic about fruit-fly-type scenarios.

Hi, as an economist on development I may say common sense is not always the best way to proof a statement. I know it is hard to accept but the same happened to me some time ago. Just a couple of references for you and for those who want to think out of the 'imposed' box: 'The Ultimate Resource 2" by Julian Simon, 1996 (ISBN 0-691-04269-1) and 'The Skeptical Environmentalist: Measuring the Real State of the World' by Bjørn Lomborg [there is an article in Wikipedia]. —Preceding unsigned comment added by 212.145.140.211 (talk) 08:02, 13 September 2007 (UTC)

It is not common sense, but is a property of the math of exponential growth. The Wheat_and_chessboard_problem is a favorite example of how difficult it is to understand exponential growth. I do agree, though, that no citation is needed. It should be easy to see that at current growth rates the population will be unsustainable in a relatively short number of years (on almost any other human time scale). Gah4 (talk) 21:19, 11 June 2008 (UTC)

Natural Increase

I noticed "natural increase" redirects to this page. It should have its own page because it does not include migration. So really, a country's population growth and natural increase can be quite different, such as in Canada, where more of the population growth is actually from immigration. 69.158.163.223 20:50, 21 January 2007 (UTC)

Graph

The first graph should be logarithmic. — Omegatron 21:25, 8 April 2007 (UTC)

Now that the graph is logarithmic, I think it is a bad idea. (a) Common readers of wikipedia, including those such as high school students and even most adults, do not understand logarithmic graphics properly. (b) for most people this gives the impression of gradual and almost stable growth, whereas the non-logarithmic version would make such an impression impossible. Use of a logarithmic graph is almost a misleading use of the information in this case, such as would be used by those attempting to downplay the fact and affect of human population growth. --GGG65 (talk) 18:13, 12 August 2009 (UTC)

I disagree that a logarithmic scale is inappropriate. I don't know where the old graph is now, but the differences in population growth in diffeent continents would be hard to discern in a non-log graph. Perhaps your concerncould be addressed better by simply swapping the position of the two graphs, placing the non-logarithmic graph first. That would convey the message of geometric growth.   Will Beback  talk  20:20, 12 August 2009 (UTC)

It seems to be extremely difficult to really understand exponential growth. Anything that will help people understand it should be done. In the Dilbert comic strip some months ago, there was one where one of Dilbert's coworkers was going to a seminar where he would be told how to turn $100 into $1,000,000. At the seminar, he is told to invest the $100 at 10% interest for 97 years. I went to my calculator to check it out, and yes it works. (Now that banks are paying 1% if we are lucky.) I suppose having both graphs is best. People have to learn to use logarithmic graphs, and still understand the results of exponential growth. Gah4 (talk) 20:53, 12 August 2009 (UTC)

The use of a Logarithmic graph in this case is not merely extremely unhelpful, it is deceptive, and its placement at the top of the article seems to serve an intention to mislead. The shallow curve of the line creates an impression of gradual growth, whereas actual population growth in the period from 1950 to the present was unprecedentedly dramatic. Logarithmic graphs are useful and appropriate in technical analyses, in which one who is well-aquainted with a particular subject (a specialist) would presume an exponential increase in a set of statistics, Thus is most certainly not the case with an encyclopedia article on world population growth; The objective here is to represent the information on the subject in the clearest terms possible for the average person, If you feel thatthe role of Wikipedia is to popularise specialist terms in by using them in non-specialist articles, please take a look at What Wikipedia is not, specifically Wikipedia is not a manual, guidebook, textbook, or scientific journal. This graph should be removed, and replaced with a non-logarythmic one immediately.

WaynaQhapaq (talk) 22:47, 18 November 2009 (UTC)

"Hispanic Race"

"However, the world's fastest growing race are Hispanic/Latino origin, who make up 44% of the world's population growth per year..."

What exactly is the purpose of this statement? Considering that "race" itself is a dubious concept, and that "Hispanic/Latino race" a completely unrecognized one in serious scholarship, the statement seem to have been inserted by a US anti-immigrant nativist. I am removing it.

199.115.9.254 20:44, 10 April 2007 (UTC)

Causes & Effects

There isn't a single thing in here about the causes of population growth, or the effects. There is a very small piece on the causes and effects of the shrinking population in some areas, but not a thing about the causes and effects of actual population growth. There's nothing about how there's a theory that it's affecting global warming, or anything else. Stars in the Night Sky 19:15, 15 April 2007 (UTC)

Well, population growth comes from people having too many kids. Global warming isn't really caused by population growth, but by out excessive use of natural resources. However, the only solution to global warming and running out of cheap energy sources is population control. Time for the world, especially the US, to work on slowing the growth rate. Gah4 (talk) 10:35, 23 October 2008 (UTC)

Consequence from Population Growth

I think population growth was okay in the past, but now it seems to be turning out bad because if the population grows forever, we would all run out of room to survive. China itself is rather crowded, that's why the law says in China, you may only have one baby. 66.191.115.61 21:26, 14 August 2007 (UTC)Cbsteffen

how does the population have to do with the death rate or birth rate i just don't get it. —Preceding unsigned comment added by Willie92 (talk • contribs) 01:32, 2 October 2007 (UTC)

the question is that if you implment such a law in say europe that already suffers from ethnic population decline while the thirdworld will brush it off , what will happen? the fact is india and the third world are responsible for most of the population growth since they can't reach transition and no one but people of such origin are responsible . china should make their one child policy softer as well since it will explode in their faces when people reach out of working age with no ss. 79.176.49.28 (talk)

Grammar

Existing sentence:

When population growth can exceed the carrying capacity of an area or environment the results end with overpopulation.

It's not the growth that can exceed the carrying capacity, it's the population itself. I'm not sure how to edit it, though. — Arthur Rubin (talk) 22:45, 9 April 2008 (UTC)

How about: Overpopulation is population exceeding carrying capacity. It may be caused by growth in population or by reduction in capacity. ·:· Will Beback ·:· 09:43, 10 April 2008 (UTC)

Several things

1. The article mentions the calculations for growth rate and ratio, but never plugs in the current data. Apparently the growth ratio is about 1% per year. What are the long-term implications of such a growth rate? The article basically stops at the year 2050. While the rate beyond 2050 is not easy to accurately project, certain mathematical truths should be mentioned. For instance, with a 1% growth rate, the world population doubles every 70 years (from 100 x ln2). That means if the world population in 2010 is 8 billion, then in 2080 it would be 16 billion, and in 2150, it would be 32 billion. In 2220, it would be 64 billion. Obviously, the growth rate of 1% cannot be maintained for 200 more years, as the world population would be 8 times what it is today, and our resources are already seriously tapped. While we don't know what the population will be, we DO KNOW that the growth rate WILL HAVE TO drop to nearly zero within in the next 200 years.
2. The world population graph done is SVG leaves a lot to be desired, for a couple of reasons: a) Aesthetically it is not very pleasing as charts go. It lacks good labels and color. b) The range of the last 12,000 years is not statistically significant. All the important information is in the last two thousand years ... growth before 0 BCE was minimal. Lumping all the data at the very end of the chart compresses it to the point where it is hard to extrapolate any accurate figure for any year in the last two thousand years. The graph should be modified to include a tear or torn edge at about 8000 BCE, then come back in with the data at around 2000 BCE. Aaron hoffmeyer (talk) 22:52, 6 October 2008 (UTC)

Tone or Style

Just responding to the notice about Tone or Style, as a person who googled for this specific topic, what I was looking for was "World population" and the estimates over the centuries. I think this article at the moment mentions "carrying capacity" / overpopulation too early; and this article should discuss theories on causes of population effect instead of "overpopulation" that already has its own article title. All best. :) 122.106.228.67 (talk) 22:47, 1 January 2009 (UTC)