The idea that "There is plenty of food for all of us and 3 billion more," is at best, a sort of sleight-of-hand trick and at worst, an out-right lie. If we wanted to grow grain on all the potential farmland in the world, it is likely that perhaps 12 billion could survive in some fashion, but those of us in the developed world would hardly call it surviving.

If we define "plenty of food" as an Australian lifestyle, with not just food, but all the things that go with it, there is no way that 9.5 billion people could live that way. It is certainly clear that 9.5 billion people could not eat as much tuna, salmon, prawns, coffee, olives, cherries, bananas, chocolate, etc. that are at their limit in the natural environment or need to be grown in specific environments. I also have my doubts about beef and milk products because of the importance of refrigeration and transportation, but the calculations are tricky.

It is hard to say "Well we would all have great food but all the other parts of the lifestyle don't necessarily go with it." When you are talking about eating like the developed world you are talking about refrigeration everywhere and a highly developed transportation network. That just can't happen with the way that we currently use non-renewable resources. If you have a transportation network you use if for other things besides food transport. If you have reliable electricity for refrigeration, you use that electricity for lots of other things. if you have highly developed manufacturing that can make refrigerators, you also make other things.

If 9.5 billion people all used as much petroleum as Australians, all the known reserves would be used up in 7 years. We currently use about 85 million barrels of oil a day. If 9.5 billion people all used oil like Aussies it would be 400 million barrels of oil a day (and that would be making the Americans reduce their oil consumption).

It's not appropriate to just say there is, and always will be, plenty of food.

You quite rightly target the root cause.....population growth.

Religious, business and politically correct stupidity, shouldn't stop the U.N. from declaring a global war on population growth.

The view that all of the problems on Easter Island were due to Europeans is not generally accepted, except among cornucopian growthists. This is from Jared Diamond's paper in Science (2007, vol. 317, p. 1612):

"Thus, major changes unfolded on Easter Island before European arrival. Those changes included deforestation; the loss of palm sap as a food and water source; switching from wood to grasses and sedges as fuel; establishing stone mulching; ceasing to carve statues, because deforestation meant no more big logs and fiber rope for transport; abandoning upland plantations, probably used to feed workers transporting statues; and (as described in oral traditions) increases in warfare, statue destruction by rival clans, and use of refuge caves. However, alternative views have been proposed.

One view is a version of Rousseau's noble savage myth: the claim that bad things began happening on Easter only after European arrival (13-15). Undoubtedly, Europeans on Easter, as elsewhere in the Pacific, did serious harm through slave raids, worsened erosion, and introduced diseases, grazing animals, and plants. But this view ignores or dismisses the abundant evidence, summarized above, for pre-European impacts.

Another view recognizes pre-European deforestation but blames it on hypothesized droughts (2). However, there is no direct information about climate change on Easter between A.D. 1000 and 1700. Easter's forests had already survived tens of thousands of years of climate fluctuations (1),...

According to a third view, deforestation was caused by introduced rats, as suggested by rat gnaw marks on many nuts of the extinct palm (15). This hypothesis does not account for all those palm stumps cut off at the ground and burned, nor for the larger number of palm nuts burned rather than gnawed, nor for the disappearance of the long-lived palm trees themselves (with an estimated life span of up to 2000 years) (16). If rats were responsible, they were unusual ones, equipped with fire and hatchets. Thousands of other Pacific islands overrun by introduced rats were not deforested, and many other tree species that survived on other rat-infested islands disappeared on Easter (16)."

Worrying about food security, esspecially back home, is nothing compared to water security, as without water, food will not grow.

Meanwhile we continue to flush billions of litres of water into the oceans, after being used only once.

It's a bit like pissing into a fan.

Thinkabit,
you failed to answer the the query about The Anasazi and the Mayans.
Easter Island has been answered by Divergence.
However it is so obvious that if all the PRESENT world population lived at the same rate of consumption that the US & Australia do, there would be no possible way the resources could be supplied.
Unfortunately the millions in underdeveloped countries that are dieing from a lack of water, food and medicines will not benefit from the cornucopian theories bandied about by denialists.
So increasing the population even more will only casue more pain and suffering there.

sarnian: You are still missing the point. So I'll try again:

Let's start again from the very first basic fact:

The food supply can either increase of decrease in the future*.

Logically, if the food supply increases then the population can increase-- this is what has been happening for the last 10000+ years since mankind has developed farming.

Contrariwise, if the food supply decreases then the population will decrease if it consumes are the same rate. However, the population can decrease by two methods: 1)starvation or 2)natural attrition due to death by old age.

However, people starve only if the food supply contracts dramatically within about 60 years because 60+ years is the average life span, ie. people starve if the food supply disappears *faster* than population can react by naturally dieing off from old age.

So the question the current worlds population dieing en masse in the future due to starvation amounts to asking if the current food supply is likely to dramatically drop off dramatically within the next 60 years. Now, there are some possible scenarios that could cause such a world-wide contraction: such as a meteorite impact, super volcano or some exotic new plant virus evolving and wiping out all the rice/wheat but these all quite unlikely. However, the scenarios that greenies like to paint about anthropomorphic global warming or running out of farm land or water are bogus. Global warming is bogus because (even if it exists) the global effects that could threaten food production are *very* gradual compared to 60 years, for example they're talking 100+ years for dangerous sea-level rise (within a hundred years the population can easily reduce itself due to natural attrition-- ie. people dieing from old age-- to handle any drop in food supply). Running out of farm land is bogus because it is simply not true-- we are actually creating more productive land each year and increasing yields each year.

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