I don’t know if I’ve ever told you this, but I’m very fond of London Zoo. So fond of it, in fact, that I’ve spent nearly two decades actively involved in its governance and administration, ever since, as a member of a group of rebellious members of the Zoological Society of London, I played a part in an insurrection against the decision, in the early 1990s, to close the place. Well, we won that one. Not only didn’t London Zoo close, but we also succeeded in shifting its whole ethos away from being merely another “visitor attraction” to being a global centre for the conservation of wildlife and the natural world.

So if any of you persist in believing that London Zoo is still an Auschwitz for animals, there solely to provide cheap and cruel thrills for gawping humans, I’d respond by insisting that, on the contrary, it’s more like the apotheosis of welfarism, about protection rather than exploitation.

None of this is necessarily truly “natural”. But again I’d counter arguments against the existence of zoos and in the following ways. Once more, it’s about protection. Any free-market bunny hugger out there (and there are quite a lot of them, believe me) who thinks the animals of London Zoo would be better off liberated from their enclosures should then take a minute or two to count the subsequent road-kill on Baker Street. Because the reason these animals need protection, as well as conservation, is that there’s hardly any “natural” left, entirely thanks to us. Which points to another reason why we both have and need zoos. It’s because of how unnatural we, as a species, have become. We’re sanitised, deracinated and denatured; urban humans, enclosed behind the bars of an infinite number of real and metaphorical concentric cages, yearn for the company of animals. This is partly, I suspect, so that we can make a stab at reconnecting with what we’ve lost.

Anyway, last week I went to a talk at the zoo about “Conservation in the Year 2050”. And it’s not looking good. Most of the world’s fisheries will have been trawled to extinction and what seafood there is will mostly consist of squid and algaeic slime. The world’s human population will have increased 50 per cent from its current level to nine billion, which will require a consequent doubling in land used for agriculture. That land is currently occupied by virgin rainforest which contains most of the planet’s terrestrial animal and plant species, so they, too, will become extinct, massively reducing Earth’s biodiversity.

A majority of all those new people will live in cities and the demand for fresh water for both them and all the new agriculture will lead, with a horrible inevitability, to massive water shortages and, consequently, water wars. Jordan already has no surface water left. The Himalayan glaciers have already nearly gone, so we won’t just have water wars, but a water nuclear war between India and Pakistan.

And all that happens without even beginning to factor in climate change.

It gets worse. Although nearly all those extra three billion people will be poor and non-white (adding to the one billion of our fellow human beings already living below starvation levels), their suffering will be our fault. That’s because the world remains enthralled to a Western, Anglo-Saxon economic system, itself the narrowest possible model of all possible modes of human and non-human interaction, which is predicated solely on the shortest of short-termism, combining a lust for personal consumption and personal greed. This is reflected in our politics, which is constrained into a tiny arc of a much wider spectrum, where most of our politicians are institutionally blinkered from seeing the bigger picture.

One of the speakers last week was a United Nations economist who showed us a bar chart of global expenditure this year. The US stimulation package was biggest – and about a third bigger than the global arms trade – but that was only about a sixth larger than bankers’ bonuses on Wall Street alone. But the bill for bankers’ bonuses was still 25 per cent bigger than the whole of aid to the non-Western world. So, once more, the most destructive type of short-term greed is literally more valuable than collective human action to help billions of people help themselves out of the kind of poverty that compels them into reproductive cycles which compound their immiseration.

Is there any hope? Not at the moment there isn’t, although I modestly proposed to several other members of the audience afterwards that, if we were serious about wildlife conservation, we should kill all the doctors and then all the farmers, and, after a couple of admittedly turbulent generations, the few remaining bands of hunter-gatherers would live in perfect ecological harmony with the natural world.

I was, of course, being satirical.

My real fear, however, is that in 40 years’ time, and with a straight face, they’ll be calling that kind of thing “modernisation” and “restructuring”…