What is scarier than Halloween?

"1987 - I bought the sweater I am wearing now"

That's why it's scary.

But in all seriousness, yeah, it's pretty scary that there are almost two billion more people that entered the world than died, within my lifespan. Add to that the growing middle classes and consumption economies in China and India, and it's downright frightening.

Is it unsustainable? Most populations grow exponentially, until they reach a stable limit, which they either don't cross, or hover about.

Just because growth is fast doesn't mean it is unsustainable, just because there is a trend doesn't mean it will carry on forever or collapse. And birthrates are dropping all across the world, so there is some feedback in the human populatio.

Those of you interested in human population growth and changes in carrying capacity may want to read this paper:

http://www.montana.edu/~wwwbi/staff/creel/bio480/cohen.pdf

A mass extinction will fix this. Assuming we get past 11/11/11 and 12/21/12, of course.

Nonsense - it's sustainable. The Stock Market will rebound and everything will be good. Companies will continue to grow at 100% per year and poor performing companies like Apple who only post a mere 85% profit over the previous year will be punished by having their stocks dumped. The industrial growth of China and the need for more metals will inspire commercial mining of the moon and Mars. Global Warming is supplying a fix for freshwater shortages - you just have to capture a slab of ice that calves off the polar sheets. In 2 years we'll have space colonies and won't need this stinkin' festering earth. The most important thing though is that the hard-working rich folks get paid more so that the 2% of top earners control over 50% of property and cash and the chasm of inequity grows just as god intended. Slashing education budgets and propping up the war machine will ensure that every nobody in society knows their place.

@Shenck #2: Unlike any other organism, humans have become reliant of vast resources which only they can exploit. These resources have their limits and we're getting to them, nor do we have a replacement for any of them. As resources dwindle we will have widespread famine and industry and societies will collapse. Then we will have this 'balance' that you speak of - it's a wonderful thing this balance, eh?

Most populations grow exponentially, until they reach a stable limit, which they either don't cross, or hover about.

Can you give an example of a population that has doubled in size during the average lifetime of an individual member of that population, then stabilized? I cannot think of any example from any species that even comes close without being subjected to massive mortality.

I fear that the current population is well over what is sustainable. I am reminded of what my undergraduate professor (JL Harper, an ecologist) used to say when the population was about 3.5 billion. "Agriculture is an experiment, and we won't know if it's been successful until humans reach a steady state."

Is it unsustainable? Most populations grow exponentially, until they reach a stable limit, which they either don't cross, or hover about.

You just asked and answered your own question!

Just because growth is fast doesn't mean it is unsustainable,

And now you are contradicting yourself!

just because there is a trend doesn't mean it will carry on forever or collapse.

I didn't say it would.

Is there something about population size that causes people to make assumptions about what other people are thinking no matter what they said or didn't say? Interesting.

MadScientist:
"As resources dwindle we will have widespread famine and industry and societies will collapse. Then we will have this 'balance' that you speak of - it's a wonderful thing this balance, eh?"
I'm certainly not saying we should just sit back and let Malthus take control. Permanent, unending growth, obviously that's not going to happen. But populations don't limit their size /only/ through spectacular crashes.
"These resources have their limits and we're getting to them,"
Are we really though? In the 70's people were saying that there already wasn't enough food and the like and that there was going to be a massive die off, but the predictions were wrong.
I am not saying our resources are unlimited, but 'limited' and 'ZOMFG we're all going to diiieee" are two different things.

R. Simons:
"and we won't know if it's been successful until humans reach a steady state."
Right, and you will probably also remember that not all populations are what used to be called 'r-selected', and that a population can reach a steady state without catastrophe, that's my question, are we going to be a few billion people over the 'carrying capacity' (and what's that really even mean for a technological, nature-manipulating species like us anyway?) and have massive die offs, are we going to overshoot it exponentially or will we meet it logistically?

G.Laden
"Is there something about population size that causes people to make assumptions about what other people are thinking no matter what they said or didn't say?"
So why is it scary then, scarier than halloween? I guess I don't follow what you're saying then. "Sustainable" in a normal sense means, 'can it possibly go on', BUT it has taken on a different meaning, especially in scientific discourse. If a city grows so large that you can't use the beaches for swimming because there's permanent sewage induced algal blooms, most people would say 'that's unsustainable', but all it really means is no public swimming.

Schneck, if you actually want to know what a carrying capacity means for a species like ourselves, you can read the paper that I linked...

Note that the second derivative of the rate of growth has turned negative, the last billion took as long as the billion before (12 years). All the earlier periods the time to add 1 billion decreased from one billion to the next. Its sort of consistent with the fall off in fertility that is seen. Look at the number of births per woman in mexico and other developing countries and you see very rapid falls in one generation. (In fact in 30-40 years Mexico may well as a whole be older than the US). If we educate all women and give them their full freedoms they may decide that children are not worth the bother and that will solve the problem. See South Korea for an example of where women are deciding that children are not worth the bother.

The Population explosion is indeed pretty scary and unsustainable.

I think Human Induced Rapid Global Overheating (HIRGO) combined with Peak Oil and perhaps further violent global conflict is going to thin our numbers very horribly and tragically - unless we take charge and make a very strong effort to reduce population ourselves by choice instead.

The usual "four horsemen" of Famine (Africa), War (SW Asia / Middle East), Disease (swine/bird flus, ebola, malaria?) and False Prophets (Tea Party? Obama? Ayn Rand? The Chinese ideology cult? Jihadism) are already hard at work on the too-many-of-us problem, sadly.

The hasrh stark maths and limited finiteness of our planet just do not allow for constant economic and population growth our ecomists rather insanely seem to think can happen.

I read in Dr Susan George's A Fate Worse Tahn Debt book written back in the 1980's that for the whole world to live with the quality of life level of western Sydney at the time would require about five Earth's worth of resources. The implications of this are exceedingly grim.

I find this situation more miserably depressing than scary however.

Typos again. I did preview, I swear, sorry. ;-(

A Fate Worse Than Debt :

http://books.google.com/books/about/A_fate_worse_than_debt.html?id=jgDI…

Up there with Orwell's '1984' as one of the most powerfully written, convincing and yet depressing books I've ever read.

Aha! Not exactly the quote and situation I described in #12 but a search found this source :

http://www.greenchange.org/article.php?id=5302

which notes :

Humanity would need five Earths to produce the resources needed if everyone lived as profligately as Americans, according to a report issued Tuesday. As it is, humanity each year uses resources equivalent to nearly one-and-a-half Earths to meet its needs, said the report by Global Footprint Network, an international think tank. "We are demanding nature's services - using resources and creating CO2 emissions - at a rate 44 percent faster than what nature can regenerate and reabsorb," the document said.

I wish I could see a way around this problem - of letting everyone on the planet live with the Western lifestyle and quality of life that I (& I'm guessing almost everyone who reads this blog) has.

But its a mathematical and environmental impossibility isn't it?

Too many people. Not enough resources on the planet.

A population that simply *has* to be cut and simply has to find ways of living much more sustainably and yet cannot or will not - refuses to - do so.

We need to reduce our numbers voluntarily. We cannot allow the huge populations of India and China to live their lives as well as we do, with the quality and things we have. It is also utterly hypocritical and unethical of us to stop them doing so, to say they can't have what we have. Plus we're just NOT going to voluntarily give up *our* quality of life to fix things and even if we did we dont number enough to offset their rise in living quality.

I despair at this situation, I really do, I can't see any halfway plausible way out of it.

As Futurama's Bender would say : "We're boned." :-(

Schenck: I'm not using the stupid incorrect definition of "sustainable" that means "icky" or "not what I wanted."

I mean "sustain, can't" .... and population grown of one billion people every few years isn't. And no one predicts that it will happen, by the way, though the curves different predictors predict are all different (and I've not proposed, critiqued, or agreed with any of them).

Lyle: It is a drop in fertility AND a drop or halt in the increase of age at death. IIRC (not looking at the data now) the dropoff in fertility may have been a bit earlier but unnoticed by the continued increase in age of death. Which, of course was not sustainable (there's that word again) so it stopped masking fertility drop.

Sharon Astyk (Casaubon's Book) has an excellent post on this:
http://scienceblogs.com/casaubonsbook/2011/10/7_billion_understanding_t…

There are a fair number of examples of populations following a logistic growth curve, but overshooting carrying capacity and making a 'J-curve' population crash. Humans have many of the characteristics usually associated with K-selected organisms. Creatures which can sustain a 0 growth population at or just below the carrying capacity. On the other hand, we conduct ourselves like r-selected organisms, successional beings which destroy our habitat and make it unable to sustain us.

My guess, and only a guess, is that our population will be crashed by a global epidemic, or a series of global epidemics.

As someone alluded to above, the best way to slow populstion growth is for women to have their first child at a later age. Someone, maybe Sokol, did the math on this back in the 70's or 80's.

GL:
Ok, right, you're talking about the impossibility of us having +1billion/decade, agreed, that's not possible. So why is it scary? It does not mean that we're going to have a massive pandemic killing a few billion people, it does not mean that we're going to have mass starvation with a few billion people dying of starvation and thirst, and it does not mean that we're going to have a few billion people dying in a global flood. It /could/ mean any of that, but it just as equally could mean that our population growth rate tapers off, and that /is/ what we're seeing everywhere, in the west, and in the 'undeveloped world'. In the west it happened slowly over decades and is now pretty low, and in the 'undeveloped world' its certainly lagging behind the west, but its dropping at much higher rates. People are moving from having 8 children to having 0-2 in a generation.
Further, as far as starvation and water resources, we have a much higher capacity for food production today than we ever had before, and we have much better technology for creating drinkable water than we ever had before. Also, a threatened population can, today, move much more easily than it could even a generation ago, to places where there is abundant, even high waste, of food resources.

We're not lemmings, and while our history in, say, the american west is more like an 'r' than a 'k' selected species, those terms don't really hold meaning for humans anyway.

J. Thomerson
"As someone alluded to above, the best way to slow populstion growth is for women to have their first child at a later age. Someone, maybe Sokol, did the math on this back in the 70's or 80's."
In some ways this is, as i understand it, similar to lowering lifetime reproductive success, which would be similar to having only 1 child, even if you have them when young. The exception to that is you still get a cumulative effect, because you could have many generations overlapping at once if everyone has children when young.
Another alternative is to skew the gender ratio torwards males. And notice that places like India, its currently generally illegal to ID the sex of a fetus, because people are preferentially aborting females. I'm not saying that's what we should be doing, but its interesting that the actual social response corresponds to what the management response (in, say, a wild population) would be.

I just want to point out that lemmings aren't lemmings. Or, more accurately, what people think lemmings are is not what they are.

I won't rest until every lemming and vole is paid out in full for their infamy in driving poor Disney camera crews over cliffs in their mad Muridaenan frenzy.

"No one anyone knows today was born prior to this interval."

Well, there are still of few of them left. (I just went to my grandmother's birthday party.) Can anybody think of another species that has quadrupled in size globally within the lifespan of one individual?

There's only one solution I've ever really been able to come up with. Universal contraception, for both genders, saturating the human food and water supply.

The only way to conceive is for the man and woman to both agree, then to go on a specialized diet that counteracts the contraceptives in both the man and the woman. Children are never conceived without 100% mutual consent in both the man and the woman.

(Now some cultures will object to the idea of women being given a choice. Some religions will object to contraception. Fuck them. It's not just their damn planet; it's everyone's, and there is absolutely no reason to give religion respect if all it's got going for it is scribblings in a moldy old book.)

Without this, human population will lead to global catastrophe, and it will be a human catastrophe, which will mean an unimaginable amount of suffering. Way, way beyond anything in Soylent Green. Think Irish Potato Famine, worldwide, forever.

Warren, when do you think various countries will figure out how to put that in other people's water?

When I finished my radiation treatment I got to keep my mask, and all the people at the hospital said I ought to use it as a Halloween costume. I'm still not sure how, unless I want to go as a brain cancer patient, which is both scary and offensively tasteless.

@Schenck: You're right that ecosystems tend to reach equilibrium, but only if they grow slowly. Do you know what happens in a lake when there's an algae bloom? The fish suddenly have far more food than they need, and the lake can sustain many more fish, so there's a population boom. The population grows so quickly that there isn't enough time for the ecosystem to rebalance. Suddenly there are far too many fish, no algae, and no oxygen in the water. Nearly all of the fish die.

As far as we know this population growth is pretty unprecedented. Therefore, people won't really know how to deal with it. That's one reason why agriculture has become so tainted. There is so much pressure to grow/herd large quantities of food, therefore it's done in an unsustainable manner.
It's going to take a lot of painful trial and error.