He's just repeating crap that's been said for centuries "the earths too populated to sustain!". They've been saying it forever, yet populations are still growing and so is food production.

"the cull during this century is going to be huge, up to 90 per cent. The number of people remaining at the end of the century will probably be a billion or less. It has happened before: between the ice ages there were bottlenecks when there were only 2000 people left"

The first part is laughable, his citation was a decrease in rice production 'predicted' because of global warming. At worst (if rice went extinct) only about 2 billion people would be at risk of potential starvation, however as the temperatures increase so do the ranges in which plants grow so when rice isn't producible other food will be and these foods already have a high productivity for plants. For the majority of the century rice production would likely be switched between the different types of rice; areas that start getting more droughts would end up growing drought resistant strains and in areas that get flooded, well then you'd grow the deep water rice.

The last part of that quote is just full out laughable. There's no evidence of significant decreases in human population in the early 500,000 years of human existence. The biggest population declines in humanity have happened relatively recently, namely the black plague and the spanish flu and all the major disease outbreaks. I'd love to hear where he got th figure '2000' from, because that would have shown in our genes.

If the human population really had dropped to 2000 people, the human race would have gone extinct. If he's talking about modern humans (us) then this is 100% bullshit, because we haven't seen anything like an ice age because we've been around for 10,000 years. If he's talking about the Cro-Magnon then it's BS again because they largely supplanted the Neanderthals by adapting to the warmer weather better. If he's talking about... oh wait the humans that lived through an ice age were the Neanderthals, which pretty much thrived during it, they lived in Southern Britain and Northern Britain at the time was a glacier! I mean his claim is laughably moronic, because the one time when homo sapiens were truly at risk in the Ice Ages we would see it, but the Neanderthals lived throughout most of Europe and the Middle East.

Here's a link to prove my point, http://upload.wikimedia.org/wikipedia/commons/1/1d/Carte_Nea... the red dots are where Neanderthal fossils have been found, and it even shows where the glaciers extended to during the Ice Age.

I mean, if you look at modern human population estimates, yes it's been below 5,000... because we'd just evolved! The lowest estimated population is before fossil evidence of modern humans, IE pre-8000BC. A similar thing will have happened with the Cro-Magnons, as they simply expanded and supplanted the Neanderthals, likely the same as Homo Sapiens Sapiens did to the Cro-Magnon. Human population likely never dipped below hundreds of thousands because a new species simply overtook the last. In fact Homo Sapiens Sapiens came right at the advent of agriculture when humans stopped being migratory and were truly affected by environmental change (IE you couldn't just follow your food).

/Rant over.

Summary: This guy's more quack than a duck.