Population growth and a global food crisis.

For most of the last eighty years or so, we humans have been on a remarkable winning streak when it comes to food. The so-called Green Revolution that came about between the nineteen forties and nineteen seventies produced better seeds, better fertilisers, better machinery, and, at least as a global average anyway - a whole lot more calories per hectare. But in the last few years… something’s changed. Look at these maps from a brilliant recent piece in the Guardian. They show how climate breakdown is beginning to hit the world’s food system now — not in twenty-fifty, not in twenty-one hundred — right now. Fields flooded in China. Record droughts in southern Africa. England’s second-worst wheat harvest since records began. France’s smallest soft-wheat crop in forty-one years. And in the United States, the driest autumn ever recorded, with over twenty billion dollars’ worth of crops wiped out. And all of these climate related impacts occurred at barely one-point three degrees Celsius of warming above pre-industrial levels All of that might quite reasonably raise the question: can we keep feeding a growing population on a hotter, more volatile planet? And it turns out that the answer is not quite what you might be thinking. Hello and welcome to Just Have a Think For decades, global crop yields were climbing steadily upwards. But in the last ten to fifteen years, that trend has begun to level off. And if we stay on a high-emissions pathway, the latest modelling suggests yields of staple crops —particularly maize, or corn — could fall by as much as a quarter by the end of the century. That’s a big deal, because maize is one of the world’s most important calorie crops. It feeds livestock, it feeds people, and it forms the backbone of food security in large parts of the Global South. And the thing is — these projections aren’t wild speculation. They’re based on real-world events we’re already seeing. The takeaway from all this, according to most experts in the field, is pretty straightforward. Our agricultural system was designed for a climate that doesn’t exist anymore. And the climate trajectory we’re on now is really only just getting started. Now, of course the minute you start talking about food stress, there will always be people who jump in with a comment like: “Well, the real problem is too many people. ” But is that being just a little bit too simplistic, I wonder? It’s certainly true to say that global population IS still increasing. According to the website Worldometer, we’re now at well over eight billion, and UN figures suggest we’re heading for around nine-point-six billion by mid-century, with a likely peak of just over ten billion by the end of the century. But while absolute population numbers are rising, as an inevitable result of the replacement model so beautifully explained by dear old Hans Rosling many years ago, God rest his soul… the actual global fertility rate - in other words the average number of children being born per female - is doing the exact opposite. Back in the 1950s, the average woman worldwide had nearly five children. Today, that number is about 2. 3. And it’s still falling. Keep in mind that for a country’s population to remain at a stable level – not going up and not going down, that fertility rate statistically has to hit an average of two-point-one children for every woman. But have a look at this chart from the brilliant website Visual Capitalist. It shows us that China is now down to around one child per woman. The United States is at one-point-six. India — long seen as the world’s demographic engine — is hovering around two and is projected to slip below replacement level very soon if it hasn’t already, and Brazil is down at about one-point-six or one-point-seven. The only region still well above replacement is sub-Saharan Africa, where fertility is between four and five — but even there, the direction of travel is clearly downward. So, population is still rising, but fertility is falling fast. How can both be true? Well, let’s hear what Hans Rosling told us about it. We have 2 billion children in the world. The between 15 and 30 years of age. These are rounded numbers. We have 1 billion 30 to 45. 45 to 60. And then we have my block. 60 years and older. We are here on top. This is the world population today. And you can see there are 3 billion missing here. Only a few of them are missing because they have died. Most were never born. So, this is what we have today. Now, what will happen in the future? Do you know what happens to old people like me? They die. Yes – there was someone here who works in hospitals. So, they die. The rest, they grow 15 years older and have 2 billion children. These ones are now old. Time to die. And then these ones grow 15 years older and have 2 billion children. This one dies. And

the rest grow 15 years older and have 2 billion children. Ah! Without increasing the number of children, without increasing the length of life, we have three billion people more by this big inevitable fill up of adults, which will happen just when the large young generations grow up” But the key point here is that this is temporary phenomenon. Right now, we’re living through the biggest, and probably the last, great swell of human population. Once we get past mid-century, global numbers start to stabilise. And after that — barring dramatic policy changes — they’ll begin to decline. The socio-economic implications of that decline are not insignificant. We may see whole economies collapse as fewer and fewer working age people try to support more and more retirees in an upside-down triangle that simply does not work in our current global financial system. That’s a whole video in its own right, and it’s a challenge that should definitely not be taken lightly, but it’s a bit outside the scope of what we’re specifically focussed on today which is food. The real challenge for food producers then, is not endless exponential population growth. It’s actually all about how to navigate the finite period of peak demand as we move through this century, all while our global climate is destabilising, ecological tipping points are being exceeded, and extreme weather events continue to worsen and become more frequent. Over the next thirty to fifty years, we need to produce food for roughly an additional one-point-five to two billion people. At the same time, if we don’t get emissions under control, climate models show we could lose around twenty-four percent of global caloric yield. So, it’s a race, isn’t it? A race between rapidly worsening climate impacts… and our ability to innovate. Now there is some good news here. We do have lots of tools at our disposal that could be rolled out at massive scale very quickly indeed. Stuff like climate-smart farming, regenerative practices, better crop genetics, better water management and cutting food waste. And of course, eating fewer resource-intensive animal products in wealthy countries would arguably the most positively impactful adaptation of them all. But, in all; honesty, I’m not holding my breath on that one. There is a whole other set of technologies though. Much newer and much more radical, that might play a surprisingly important role. Oh Dave, you’re not talking about lab grown meat, are you? I hear you cry. And, well, yes, ostensibly I am talking about lab grown meat… but DON’T SWITCH OFF JUST YET! There’s stuff here that I think you really need to know about because, like it or not, it’s coming our way fast. A few years ago, I did a video on a report by a think tank called ReThinkX. They argued that a combination of cellular agriculture and precision fermentation could transform the food system, slashing emissions, freeing up vast areas of land, and reducing reliance on livestock — all by the twenty-thirties. That all sounded a bit overly ambitious at the time. And in all fairness, parts of it still are. But what’s interesting is that the core science has actually proven out. We CAN now economically grow animal cells in bioreactors. We CAN program microbes to produce milk proteins, egg proteins, fats, and all sorts of other ingredients. And contrary to popular belief, some of these foods are not just lab curiosities anymore. Singapore approved the first cultivated chicken back in twenty-twenty. A few restaurants in the US served cultivated chicken in twenty-twenty-three. And in twenty-twenty-four, Singapore even saw the world’s first supermarket sale. Admittedly only a hybrid product containing about three percent cultivated meat — but a genuine, legally sold, consumer product nevertheless. So, what is a cultivated chicken then? Does it eat fine caviar and enjoy nights out at the opera? No. Not that sort of cultivation. Cultivated chicken is real chicken meat grown directly from animal cells rather than from raising and slaughtering a bird. Scientists take a small sample of chicken cells and place them in a controlled environment—usually a stainless-steel bioreactor—where the cells are fed nutrients like amino acids, vitamins, minerals and energy sources that mimic what they’d receive inside a living animal. The cells multiply and mature into muscle and fat tissue, the same types of tissue that make up conventional chicken meat. The end product is biologically identical to chicken, but produced without farming, slaughter, or the environmental impacts associated with conventional poultry production. You might not like the sound of that, but nowadays the end results are apparently indistinguishable from slaughtered meat, can be engineered to have exactly the right amount of fat to be as juicy and tasty as the real thing, contain none of the pathogens that can be passed on by livestock, and require something like ninety percent less water and up to ninety-NINE percent less land to produce. If we ignore those numbers, then at least in my view, we need our bloody heads examining.

Meanwhile, precision fermentation has quietly moved ahead even faster. That’s a biotechnological process where scientists engineer microorganisms like yeast, bacteria or fungi to act as microscopic factories that produce a specific desired molecule — for example an animal protein, or an enzyme or a fat — by inserting the gene that codes for that molecule into the microbe’s DNA and then growing it in controlled fermentation tanks where it uses nutrients to make large quantities of that target compound. Once the fermentation is complete, the product is extracted and purified to produce ingredients that are MOLECULARLY IDENTICAL to their traditional animal-derived counterparts without requiring any livestock or plant agriculture. Companies are now making real dairy proteins — whey and casein — without cows. In Israel, several cafés and restaurants are already serving cow-free milk products made with fermentation-derived proteins. In Europe, companies have submitted applications to regulators for similar ingredients. You can buy ice cream, protein shakes, and creamers using these proteins in various markets today. They taste like dairy because — chemically — they are dairy. They’re just not made by a cow. Is this all happening as quickly as that original ReThinkX analysis predicted? Probably not. But is the direction of travel correct? Well surely it must be, mustn’t it? I mean these technologies clearly work. They’re scaling extremely quickly and they’ve ARRIVED at the economically affordable end of their development cycle. They’re on supermarket shelves. And they use a tiny fraction of the land, water and emissions compared to conventional dairy or meat. Just like everything else we talk about on this channel, they’re not a silver bullet, obviously. But they’re a new tool in the toolbox. And right now, we need all the tools at our disposal. The trouble with these kinds of debates, apart from the ignorant and unfunny morons who write the words ‘Soylent Green’ in the comments section, is that they always seem to reduce themselves to some sort of existential battle between “traditional farming” and “lab-grown steaks”. But that’s far too simplistic. The real future is probably an all-of-the-above approach. We can’t flick a switch and instantly move to a completely different global food production system. So, in the near to medium term we WILL need smarter farming that builds soil health. We’ll need crops designed for heat and drought. We already desperately need better global trading systems that move food from surplus regions to deficit regions more flexibly. We’ve also got to get to grips with the absolutely shameful way that more than thirty percent of all food produced gets tossed into the garbage. That’s an absolute disgrace. And yes — shifting diets in richer countries away from meat is definitely a thing. I’ve followed a plant-based diet for eight years, having previously been a very enthusiastic carnivore. It won’t kill you, you know. And there are so many plant-based options now, you won’t get bored either. Even if you cut out red meat and make chicken your meat staple it would make a big difference. Anyway, rant over. The point is, the real story ISN’T about doom and gloom. It’s about agency. The scary maps and charts in that Guardian article aren’t a prophecy of collapse. They’re a warning sign — and a to-do list. If we act now, say our food experts, then feeding 10 billion people on a warming planet is absolutely achievable. You may not agree with that assertion of course. You may think it’s too optimistic, or you might think it’s too pessimistic. Such is the way of the world I suppose. Either way though, it’d be interesting to hear your view, so as always, the place to leave your thoughts is in the comments section below. And while you’re there, don’t forget to like and subscribe AND leave a suggestion for a video topic to get yourself a chance to win one of these exclusive Just Have a Think hoodies. That’s it for this week though. Thanks, as always to the amazing group of people over at Patreon dot com forward slash just have a think who keep the lights on and keep ads and sponsorship messages out of all my videos. And thanks to you for watching this far. Much appreciated. Have a great week. And remember to just have a think. See you next week.