Long before chemistry was a formal science, humans were experimenting with substances to solve problems, cure illnesses and make money. In his book "The Age of Alchemy: How Early Innovators Shaped Modern Chemistry" (Profile Books, 2026), author Kit Chapman, a science journalist and honorary researcher at Falmouth University in the U.K., traces how this ancient, protoscientific tradition shaped the world.

From our ancestors' early use of fire to some accidental — and disastrous — pyrotechnics in the 14th-century French court of Charles VI, Chapman reveals how early innovations across the world paved the way for modern science.

Live Science spoke with Chapman about his book, which has been short-listed for the 2026 Royal Society Trivedi Science Book Prize.

Hannah Osborne: The book is full of brilliant historical anecdotes that bring all of these alchemy breakthroughs into context. What was your favorite one and why?

Kit Chapman: I mean, you can't go wrong with a man trying to turn his own urine into gold, I think. Hennig Brand [who accidentally discovered phosphorus in the 17th century] was one of my early touchstones. I've known about this story for a while. I've always thought, "How can I get this into a book? What's the link?" Obviously alchemy provides this fantastic base. He bankrupted two wives to try and fund his 1,500-gallon [5,700 liters] urine habit — and then he gets something [phosphorous], against the odds.

This is the first element we can actually put a name to. This is the first person we can say actually discovered a chemical element, and it's an alchemist in the purest sense of the word. Then, of course, he tries to keep it secret. He sells it, eventually, to a friend, and his urine goes on tour around Europe, showing the kings and queens this glowing pee, before suddenly, [chemist and philosopher] Robert Boyle actually works out exactly what's going on.

That, to me, sort of encompassed everything I was hoping for in the book. There's a fantastic story there that's about human connection. There's the unraveling of mythology, and theology and belief, and starting to look at science. But there's also real practical stuff going on there. He didn't know what he was doing. He just didn't know why he was doing it, and that I found fascinating.

HO: You make the point that these people weren't thinking, "Oh, I'm going to do chemistry." How important is that for understanding how these early innovations shaped modern knowledge of how things work?

KC: I think that's essential. We often look at science as something separate from the real world, and one of the things that I really wanted to do with this book was to illustrate that science is going on in every profession. It's going on in every home, continuously; it's going on in our bodies continuously. It's everywhere.

Science is a way to understand what's going on in the world. It is not a separate thing from culture, from belief, from trade, from globalization, from discovery, from just getting on with life. I wanted to bring in the potters, the weavers, the bakers, the urine salesmen — which was an entire thing that I didn't really know I had to go down. I found it fascinating.

And, of course, [there are] artisans. When we start looking at the first actual chemistry that's being done, it is people trying to create beautiful works of art, perfumes, things like that. It moves away from survival and into this ecstatic beauty, and that, to me, encompasses what I love about the history of science. It's bringing all of these threads together and making discoveries not necessarily where we think we're going to find them.

HO: You mentioned the beauty of it all, and the perfume. One of the chapters I really enjoyed was the first chemist who was a female perfume maker in ancient Assyria.

KC: Tappūtī Bēlet-ekallim. The fascinating thing is that the only reason we know her name is that she put it down in cuneiform. She wrote it down. She may well have been a slave; perfume makers were often slaves. She was certainly a woman who was working in the palace. She was working with another woman whose name, unfortunately, we've lost to time.

What I find fascinating is that we now have this person who was one of the working class, one of the underdogs, slaving for a week to make this potion that she wrote down because the recipe is incredibly detailed. And we remember her name, but we have no recollection of the lord or lady that she was actually making it for. It's kind of class warfare throughout the centuries.

HO: I found the extreme sort of secrecy really striking — that so many of these ancient texts were lost because they were being hidden. But then you also have the fall of civilizations, so we've lost all this knowledge.

KC: It's this combination of, as you mentioned, hiding the recipes because they are trade secrets. If you look at the first alchemy book that we actually know of — "Physika Kai Mystika" — it literally translates as "natural and secret questions" or trade secrets. These were craftsmen, and, of course, they didn't want to share it with rival craftsmen. If you've got a really good recipe for making something look like gold, you want to keep that to yourself.

They use these code words — and that went all the way through into what we think of as alchemy, that sort of Renaissance period where they're talking about taking the fiery sword from the belly of the dragon, which is just wonderful and descriptive.

But you also have things like Emperor Diocletian destroying the texts in Alexandria in 300 A.D. Why did he do it? Because it was a matter of survival for him. Twenty-five of his predecessors were murdered by their own guards or died of plague and things like that ‪—‬ horrible fates. He wanted to avoid that, and the idea that [someone] could turn something into gold terrified him. It would debase his currency, so it always brings in that politics. It brings in human nature and human curiosity.

HO: Do you think there are still things we're yet to discover from alchemy from the past?

KC: Yeah, without question. Whether or not we're going to discover some kind of new, groundbreaking technology that's going to change the world, I can't see that happening. But the one thing we could see is the use of natural products in a way that we hadn't necessarily thought [of].

A great example of that is [Nobel Prize-winning chemist] Tu Youyou and the discovery of artemisinin compounds [from the] qinghao [plant], which comes from a Chinese alchemist's herbal remedies book, essentially 1,700 years ago. The fact that the best defense we have against malaria, the best antimalarials possible, comes from this ancient alchemical source indicates that there's probably more to find.

There is almost certainly more to find in terms of how they [ancient alchemists] used recipes, how they would try and make gold. Their understanding of the world is something that we don't necessarily have a full grasp of, and we're still piecing it together. There's some wonderful work being done by Matteo Martinelli and others looking at the history of, particularly of Western alchemy emerging in Egypt.

We also have things like Greek fire. We have a pretty good idea how they did it, but if you're looking for what the exact recipe [is], we're still not 100% sure.

HO: It's interesting now, watching modern equivalents taking place. We still, to an extent, try to guard our own knowledge.

KC: Yeah, we do, and I think it's actually a pernicious thing in science. We have this publish-or -perish mentality, which is that if we don't get the paper out first, obviously we lose the patent, but wider than that, we lose the kudos. There's this kind of necessity to kind of hide things. You hear about all kinds of shenanigans ‪—‬ a reviewer delaying a paper until their paper comes out, things like that, all this kind of naughtiness going on.

We've got to recognize that science has moved on certainly from the "Great Man" idea. We're now working collaboratively in teams. That is the only way that modern science gets done. The second, if there is one lesson from the book, it's that if you try and hide science, you delay progress.

The moment you actually start spreading ideas, the real ignition for me for the Renaissance and for what becomes chemistry, is the printing press. It's the fact that ideas can then be shared and accessed by everybody. The moment we start realizing that science is a global endeavor, that everyone can do it ‪—‬ man, woman, child, it doesn't matter your nationality, [it] doesn't matter your ethnic ethnicity, it's for everybody ‪—‬ the sooner we're going to start seeing some major progress that we otherwise wouldn't make.

HO: We see loads of the advances in chemistry and alchemy within civilizational melting pots. What were some of the biggest surprises to you when you were researching the book?

KC: One thing that really annoyed me was, looking through textbooks, you can look at who made zinc, and you come up with a name that came from the 1700s, or how platinum was discovered — that's a fantastic example. Platinum was discovered by a conquistador who noticed that some natives were wearing platinum. But, of course, he didn't discover it; it was discovered by the Indigenous populations.

The amount of science that came out of Mesoamerica, Central America, and the way that science was also being developed in India, it's just kind of completely overlooked. If you look at the traditional story of science, we talk about Europe. Occasionally, we might bring in China. But India, Africa, Mesoamerica, South America, North America ‪—‬ every single continent was having scientific discoveries and developments.

They weren't necessarily developments that we think of in terms of leading to chemistry, but they were dealing with social problems that they had at the time. They were tackling what was in front of them, and we always need to remember when we're looking at history to look at the context of the discoveries.

HO: Which breakthrough did you think was most impressive in terms of the materials or facilities that were available?

KC: One thing that I found sort of striking was, there's a chap called Paracelsus who is absolutely fascinating, absolutely bonkers. Paracelsus is, for me, the archetypical alchemist because he was certainly trying to revitalize medicine and get rid of humor theory and come up with all these ideas. [Editor's note: Humor theory is the idea that human health and temperament were related to four fluids in the body — black and yellow bile, blood and phlegm.] But he also believed that mermaids were real and that they were just out to steal men's souls.

He was a drunk, he had a broadsword, and yet he's the guy that was able to combine what we think of as the traditional herbalist role and the doctors. At that point, doctors weren't even touching patients. They believed that the true skill of a medical man was that you didn't even need to examine a patient; you could just sort of look at them and you'd know what was wrong. He [Paracelsus] was able to say, "No, that's not right; you need to actually test things, and you need to try things." The moment we actually combine those two different threads together is when we actually started to get what becomes of modern medicine. The number of lives that saves is incalculable, so I think that that's one of the great moments.

The other one that always comes to me is Antoine Lavoisier in the French Revolution. He made several great discoveries — the fact that matter can only be changed; it can't be destroyed [at least at low energies]. The idea that if you take something, then obviously there's got to be components to that; you're not making it out of thin air. And coming up with a list of elements in the French Revolution or just before the French Revolution, unfortunately dies, from the guillotine [when Lavoisier was executed].

That, for me, was when we started to get true chemistry. That's when all of the magic is dispelled. I think he [Lavoisier] is, for me, the French equivalent of Isaac Newton. He's incredible.

HO: For you personally, throughout researching and writing the book, what was your biggest takeaway and what was the biggest surprise?

KC: My biggest takeaway is that science happens everywhere continuously through everyone. I traveled around the world for this book; I went to pretty much all of the continents. I didn't go down to Australia; that's about it. Wherever you go, there are discoveries being made. There are people who are trying to make their worlds better.

Science is not for this elite group; it's for everyone. One of the things I try to do with this book is to show people that even if you think that science isn't for you, it absolutely is; you're doing science continuously.

There've been so many [surprises]. One of the things — this is purely because of the way that I was taught and these inherent biases that we have — but it's so easy to overlook the role of women. When you start delving into the role of women in science … You've mentioned Tappūtī; we also have Mary the Jewess. Throughout the Renaissance, we have people like Caterina Sforza and [the] very famous Queen Christina of Sweden, which I didn't mention in the book because I just didn't have space.

The one shocker for me is this book "The Secrets of Isabella Cortese," which was a man pretending to be a woman to sell his science book. For me, [it] just kind of unravels this whole idea that science isn't for everyone.

This interview has been condensed and edited lightly for clarity.

Climate change's impacts are being felt everywhere, from health and food security to extreme weather, sea level rise and collapsing ecosystems. World leaders have been slow to adapt to the warnings, despite an ever-growing body of evidence showing the compounding risks of greenhouse gas emissions.

But despite fossil fuels remaining the world's primary source of energy and emissions continuing to rise, there are changes afoot.

In his book "Despite it All" (Granta, 2026), author and journalist Fred Pearce looks at the shifts that have taken place over the last 40 years, highlighting how far humanity has come in the green transition. He believes this progress gives us reason to hope that we can eventually overcome the challenges we face today.

Pearce spoke with Live Science about his book, which has been shortlisted for the 2026 Royal Society Trivedi Science Book Prize.

Hannah Osborne: There are a lot of positive environmental stories throughout the book, including those that aren't necessarily being told. Do you think that there is a growing appetite for positive climate news now? And will it help us?

Fred Pearce: I detect a kind of desire to be told something other than it's all hopeless and there's nothing we can do. Some people are therefore saying, "Well, what can I do?" And they're very sort of personal stories about how they can contribute. But also people who think more, if you like, strategically: What can the world do, what can governments do, what, how can we influence that?

I try not to write what I think people want to read. I try to write what I want to say. And it seems to me that we do so many things so badly, whether it's managing our resources or water or handling forests or the climate, or pollution or whatever. We do things so badly that there is a great deal of scope for doing things a lot better. So, we need optimists and we need pessimists. We need pessimists to point out the problems. We need optimists to come up with some solutions or suggest where [there are] half open doors that we can push open.

I wrote this book in that kind of spirit to say "Look, yes, things are bad, yes, I'm not denying that they're bad, but there's an awful lot that we can do about it and in some cases are doing about it." That then divides into whether we're talking about human activity, our technical solutions to climate change. Tech fixes are good, not bad, which is something that can be a hard sell in the environment community sometimes, so I want to stress that.

I went to the Earth Summit 30 years ago where they agreed [upon] the original climate change convention. Back then they said we [need to] prevent dangerous climate change, but they really didn't know much about how to do it. Wind turbines were just, you know, a few masts on a hill in California. Nobody was dealing much in solar power because it was just so expensive. It had been developed for powering satellites and electric cars. Nobody was talking about [it].

We have made quite a lot of progress and it's not fast enough and CO₂ emissions are stable, they're not going down. We need to do a hell of a lot more and we may have passed climate tipping points. I'm not denying any of that, but rather than throwing up our hands or saying it's hopeless, let's get on with the tech, let's also recognize that nature is very good at recovering. You destroy a forest, a rainforest, it doesn't mean that it's destroyed forever. It will, given the chance, come back if we give it room. So let's give forests room to recover.

In large parts of the world it's already happening — in Europe, even in North America. Agricultural land is being abandoned, and when it's abandoned nature comes back and not necessarily in the sort of ways that we might think. But nature does come back, stuff regrows. We can see how evolution is being kickstarted, if you like, by the chaos that we're creating. That's not to say we shouldn't stop creating the chaos, but we can see how nature recovers.

These are things that we can recognize and respond to; giving nature room to recover, rewilding projects, therefore I'm all in favor of [them]. We're not rewilding where we're trying to garden nature to get back to some sort of perfected past, a pristine system where we thought that everything was great — pre-industrial revolution or before Europeans arrived in North America or whatever it might be. But, we can give nature room to evolve and adapt and change. We can see that nature's doing that all the time, with or without climate change and with or without humans. Nature is constantly, if you like, remaking itself.

I'm not saying nature always comes back in ways that we approve of. Let's recognize the distinction between our sort of slightly romanticized idea of what nature should be and what nature actually is.

HO: You talk about rewilding and letting nature take its course, but how do humans fit in with this? Can we adapt our own perceptions of what nature is allowed and what's not?

FP: I think we can probably forget about what's allowed and what's not. Nature will do what it wants to do. We pride ourselves on our ability to garden nature in a way, or manage ecosystems. We're not really very good at it. Nature will very often take over and do what it wants to do.

Some of the world's biggest rewilding projects have gone quite badly wrong because we haven't quite thought it through. The one I'm thinking of really is the large project in the Netherlands where they're trying to sort of recreate ancient European ecosystems and they ended up with mass deaths of animals because their conception of the ecosystem didn't quite figure out. They then largely abandoned the project because they didn't like to see large numbers of animals dying.

A hardline rewilder would say let nature take its course. I see the case for that, and often I would support that, but we have our own sensibilities and our own concerns and we are living in a world where we are very much in charge of what's going on. So while I'm in favor of standing back and letting nature take its course, we have our own sensibilities, and it's not wrong for us to want to intervene sometimes.

HO: There's a chapter on human population and fertility rates, and how this is very much a climate change story as well. We're now seeing a lot of the rhetoric around this, and rights being stripped back and taken away. What's it like for you, having seen the changes from the UN International Conference on Population in Mexico in the 80s, to Cairo in the 90s to now?

FP: It's an extraordinary story. I've been working on these issues for 40 years now so I've seen a number of changes. Some of the changes I've seen are how technical fixes somehow became a reality when they seemed very distant a while ago.

But our perceptions change too on many things. We are, in many ways, more attuned to environmental issues now than we were 30 or 40 years ago. One of the big changes that I've seen is the notion of the population bomb, which for much of the 20th century was seen as the number one issue. People would say, "Well, there's no point in fixing the climate, there's no point in reducing our pollution because there are more and more people on the planet, and we're kind of doomed for that reason."

Well, it hasn't [happened]. When I went to my first international conference, which was the UN Population Conference in Mexico City in 1984, that was all the rage. They gave the UN Population prize to the mastermind of China's one child policy, which — in terms of human rights and what I would regard as acceptable human behavior — was dreadful. But such was the concern about population issues that they wanted to give a prize to the operator of that program.

A lot has changed. A feminist agenda, if I could put it that way, and I would say that approvingly, has taken over in reproductive politics. I saw it at a UN population conference in Cairo in 1994, 10 years after the Mexico event, that we need to assert reproductive rights. Many environmentalists said that's a cop out. It was all "it's feminist perspective, but it's dooming us."

Well, it didn't, because what we found was that by and large, women wanted to have smaller families because their children got to grow up. Medical improvements meant that you didn't have to have four or five children to secure the next generation. Two would usually do, sometimes you just wanted one. Women wanted to have lives outside the home. The population people seemed to be a bit surprised by that.

The environmental agenda was a very male-dominated one for a long time. So that came as a bit of a surprise, but the net result is that we've halved our fertility rates. They're more or less down to replacement levels [of reproduction] now globally.

I'm not just talking about Europe or North America. I'm talking about almost everywhere except Africa, and African levels have come down. Sometimes they're coming down to super low levels, so that people are now talking about not having enough babies and how we can encourage people to have babies. There are parts of the world where we're down to one child per woman and even a bit less.

My argument is that we need to carry on. Not take a sort of Elon Musk approach [or] send the women back to the home and [do] reproduction and that's what their job is. We need to complete the feminist revolution so that women have more rights, can make better choices, and indeed couples can make more and better choices about the family size that they want. We can arrange things so that it is possible to have children and a career, or make it easier to do that, and at that point probably reproduction levels will come back up.

What I'm really saying is that the agenda is now vastly different from what it was as recently as the 1980s and, and into the 1990s. The population bomb is being defused, to put it simply, there's a residual momentum effect which means that our numbers will carry on going up a bit. Sure, that creates strains on the planet, but we're not now talking about double the world population every 30 years, which is what was being talked about back in the mid 20th century. It's tailing off.

We now have, if you like, a consumption bomb more than a population bomb. The global issue is consumption in the rich world, and that's what's stressing the planet now — not too many babies in poor parts of the world.

HO: Inequality between the super rich and people in developing countries is becoming more and more stark. How do we bridge the gap to make sure there's a reasonable living standard for regular people without a huge cost to the environment?

FP: The truth is, and the numbers have been done by a number of different people, a reasonable standard of living for everybody on the planet is perfectly feasible without destroying the planet.

We need to do some things better, we need to have better technology, but for me, right up there with climate change is an issue of global inequality. When I was young, it was taken [that] inequalities were diminishing and it was taken almost as read that they would carry on diminishing, and a lot of aid policies were directed towards that. That's kind of disappeared since the sort of Reaganomics of the 1980s, all the changes in the finance system and perhaps the fall of the Berlin Wall, which meant that the sort of socialist or, or equality-based agendas collapsed politically.

We're now finding increased inequality, and that, it seems to me, is a threat to the lives of millions and billions of humans, but also to global stability and our ability perhaps to manage.

Serious global issues like climate change and many others are all undermined by the political stresses and economic stresses created by rising inequality. I see them going together.

It's also clear that it's important to level up, but also level down from the obscene riches that we see among a small number of individuals, who seem to be accumulating a greater share of the world's wealth, whether we're talking about dollars or natural resources.

HO: You have a whole chapter on renewables and how they're outpacing fossil fuels. They're the cheaper alternative. How do you see the political opposition to clean energy panning out over the next five to 10 years?

FP: It's fizzling out. It's a weird political backlash and yes, any big social trend or economic trend, they all have backlashes and it feels to me like this is it. What we see in the real world is that the U.S. — not just the U.S., but principally the U.S. — are in a state of near denial about climate and they're wanting to go back to fossil fuels.

In the rest of the world, if you look at it in terms of geopolitics of [the] U.S. versus China, then the U.S. is pushing this rather old agenda of fossil fuels, and China is absolutely going to reap the benefits in many, many ways in its drive towards renewables. China has been a really bad story in the past with its coal burning — and it's still building a few coal-fired power stations. But the really big story is how China has been principally responsible for bringing down the costs of renewable energy, particularly solar power.

You can now go to the most remote corners of rural Africa and you find people putting up their solar panels to recharge car batteries so that they can run their lights in the evening or whatever it is. And then you've got megacities operating using increasing amounts of solar power. India is getting on the bandwagon as well. It's got the fastest growing solar energy economy in the world.

In the real world, renewable [energy] is mostly cheaper than fossil fuels. It is also quicker to install, you don't have to build a huge power station, you can do it in bits and pieces, bolt bits on.

Yes, there are grid issues and they need to be addressed, and there are limits on operating. There are challenges, but renewables are just growing so fast, and it is growing so fast because it is so cheap.

And it's become so cheap, to put it very simply, because the Chinese 20 or 30 years ago decided this is what's going to happen. While everybody else was sort of talking about it and fussing about it and doing it in research labs, the Chinese kind of got to grips with it. I remember back in the 1990s talking about people who were going into China and coming back and telling me stories about how the Chinese are really serious about renewable energy. To be honest, I didn't quite believe them, but they were right, and 30 years on, the world is living with the benefits. That's true whether you're talking about Europe or rural Africa or big cities in Asia or wherever. It's coming.

There will be different solutions in different places and there are undoubtedly things that are harder to do than, you know, running our national grids on renewable energy, which is becoming really quite easy and something that everybody wants to do. The cement industries, fertilizers perhaps, some of these industries will take some more technical innovation. But it's happening, these are technical fixes that are working in the real world. Will we do it in time? Well, we're a bit late on the case, but we are on the case.

HO: We're now seeing a massive rise in AI data centers as well. Is this bad tech, shall we say?

FP: It's a serious issue. Partly because they're growing so fast — they can't just plug into the grid because the grid really can't deliver, so these companies are developing their own energy systems. Even in the U.S. they are very often renewable systems because they're cheaper. If you've got a data center out in Texas, then you're going to use wind power or solar power because it's cheaper and you're in control of it.

I suppose we reach a point where [we have to decide], do we want to reduce our use of energy or have almost as much energy as we want, but just green it and green it very fast. It is true that if all the renewable investment is going into electricity for data centers, that leaves less investment for other sectors of the economy, so I'm sure there are trade-offs, and I'm not saying that we should embrace data centers. But they can be a driving force for adoption of different forms of energy, renewable energy, and for perhaps changes in the grid systems as well.

I think we can have both. I think we need to have both because we're probably not going to stop the data engines, so we've got to find ways of greening them. There are issues and there are challenges ahead, and I don't want to diminish any of those, but you know, let's, let's be hopeful.

The title of the book uses the word hopeful rather than optimist because I don't want to sound Panglossian, but I do want to inject some hope.

HO: When you started writing the book, what did you hope people would take from it, and did that change after you'd finished?

FP: Well it kind of evolved. It began as an idea to sort of [be a] retrospective of my reporting, and then the publisher said, "Well, the story changes rather a lot along the way, so rather than just showcasing your reporting over 40 years, why don't you showcase the change, and be hopeful in the context of how things have changed over the last 40 years?"

That was [the] kind of starting point, and we sharpened up on it, as we went along it did become "Despite It All" and you know, the title is important, and not diminishing the "All." There's a lot of bad stuff out there, but despite it all we can have hope and we can find, develop and demand solutions.

HO: Did you find anything during the process of writing the book that surprised you?

FP: As I say, it started as a sort of retrospective project and going through it, [there were places I went years ago] and it did look bad, then I checked up on what had happened over the intervening years and suddenly things looked a lot better.

I went to Alaska and saw how the conflicts over managing caribou herds and the huge migrations that go on and it felt like that was doomed. I was talking to people who were hunting the animals and they were trying to protect them because they wanted to hunt them, therefore they wanted them still to be there, which is kind of counterintuitive for many environmentalists, but you know, they were the best defenders of the caribou because they ate them.

But it felt doomed, and yet 20 years later I checked out the numbers and the population of that herd has doubled and tripled. So stuff does happen and I suppose my surprise was how much good change I found when I looked into it further. Maybe that's me being better at looking for good news stories. I've written quite a lot of "bad news" books over the years and done a lot of "bad news" journalism over the years, so I certainly don't discount that. But if you step back and you think, well did good stuff happen? Well, yeah, sometimes it did.

The bison herds are coming back on the plains of parts of North America, if you go to Montana. The ranches are disappearing and big areas are being set aside for bison, and I've been seeing how farmland in parts of southern and eastern Europe has been abandoned over the years. It's not necessarily good news that we're abandoning farmland, but again, the way that nature comes back and woodlands are growing, there are more forests in Europe than there have been for probably centuries.

There's a lot of bad stuff to say. But it does seem to me that we have to not just cling onto, but embrace good stuff and try [to] take it forward.

Something I really hadn't thought about till I went back was what were the big issues in the 1980s, 1970s when I started out. Well, all our industrial rivers in Britain were filthy. Now our industrial rivers are relatively clean. It's our agricultural rivers that are filthy, so, I mean, there's been a big change there.

Nobody has to talk much about the ozone layer now. That was the number one issue in the mid 1980s, and the absolutely terrifying prospect if we hadn't fixed that. But it's been fixed.

We banned the chemicals that were doing it.

Remember acid rain, lead in petrol. They were hot topics, headline news, part of the rise of the environmental agenda in the 1980s — and they're the ones that we don't have to talk about anymore.

Now we're talking about climate change. I think there are other things coming up. I think the issue of nitrogen pollution is a fast growing one, and we need technical solutions to that.

The green revolution of crops, the high-yielding crops, which got us out of a cycle of ever worsening hunger and famines in the mid 20 century. That was a solution which created new problems. Those crops grew very well, but they required large amounts of inputs, including water, and water is now a growing issue — finding enough irrigation water, but also fertilizer and other agrichemicals. We're now reaping some of the bad effects of that, and we need to solve that. Scientists I know are working on, if you like, high-yielding crops that don't require so much fertilizer and don't require so much water.

It's doable because as I think I said at the start, we do a lot of things really very badly, but that does give us a lot of scope to do things a lot better, so let's get on with it.

This interview has been condensed and edited lightly for clarity.

Great auks (Pinguinus impennis) were large flightless birds that thrived on rocky islands in the North Atlantic for thousands of years. However, humans hunted them to extinction within just a few hundred years, targeting the auks for their feathers, fat, meat and oil. The last breeding pair was killed by a fisher off the coast of Iceland in 1844, and the last sighting — of a single male, and potentially the last of its species — was off the Newfoundland Banks in 1852.

In his new book, "The Last of Its Kind: The Search for the Great Auk and the Discovery of Extinction" (Princeton University Press, 2024), anthropologist Gísli Pálsson recounts the final years of the great auk, using accounts and interviews from Victorian ornithologists John Wolley and Alfred Newton, who realized that species extinction was not something confined to the past but a tangible process that humans can cause.

In an interview with Live Science, Pálsson discusses the background to the book, the lasting legacy of the great auks' demise and whether the species could or should be resurrected.

Alexander McNamara: What is a great auk, and what happened to it?

Gísli Pálsson: The great auk was a tall bird — 80 centimeters [31 inches] and quite thick with lots of meat — and it was flightless so would nest on skerries [small rocky islands] where it could climb up. [It lived] In various spots along the North Atlantic and in North America, and humans exploited it for millennia — the oldest images we have [are] from a cave in France, close to Marseille from 27,000 years ago. The biggest colony was probably in Newfoundland and Indigenous groups in North America hunted it for quite a long time. We have early anthropological reports and archaeological evidence, but this was largely for religious events, and symbolism, [for example] the Beothuk [Indigenous people] captured eggs and used them in rituals.

The great auk was hunted in the Scottish Isles, Norway, Iceland and some other places — but the major slaughterhouse of the great auks was in Newfoundland. It was European sailors, French and Portuguese, in the 16th and 17th centuries. They would hunt great auks in their thousands, decimating the local stock. At the same time, they would kill the Beothuk, and so this was genocide plus near extinction of the great auks. The European sailors were there to catch fish, but they needed food on the way back, so would fill their boats with great auk, salt the meat and sail on to Europe. Some of my colleagues have [said] this was the first fast food stop in the world.

Iceland was also an important colony. There are old Icelandic maps that show several great auk skerries, but the main colonies were in the south, close to where the recent eruptions are. For centuries [the biggest] was probably the great auk skerry, which sank in an eruption in 1830, so the bird had to find new breeding grounds. From 1830 to 1844, it would nest on the famous Eldey, which means Fire Island, and that's the place where the last pair was caught on June 18, 1844.

AM: How do we know about the final days of the great auk?

Miraculously a pair of British naturalists [John Wolley and Alfred Newton] came to Iceland in 1858, 14 years after the final pair was killed. They wouldn't know that, but they were hoping to get a bird or two and an egg for the museums and their studies. They were unable to go to Eldey because the foreman they had hired said it was too risky. Entire crews have been killed in the battle with the island and the ocean — it's a long history of drownings and accidents. So they were stuck on southwest Iceland, terribly disappointed they couldn't get to the island. Instead, they decided to take interviews and notes. John Wolley wrote five notebooks, the "Gare-Fowl Books" [which are] now stored in Cambridge University library. He died a year after the expedition to Iceland, but Newton lived on.

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[After six weeks, they] returned to England, and Newton became the first professor of zoology in Cambridge and quite a big name in environmental protection and in bird studies. When I came somewhat accidentally across the "Gare-Fowl Books" I was stunned. I sort of doubted if the source existed and was readable. I decided to buy a copy, digital images of the whole thing, 900 pages, and it would take me months to read the handwriting and to transcribe some of the key points I saw in the interviews.

This was the meat of my book, but in the middle of writing, it dawned upon me that I had a vital source in my hands that no one had really tracked thoroughly. This was evidence of an extinction, and evidence which eventually led to the recognition of extinction as an epistemic fact, something to be explored and scrutinized by scholars. I also realized that I was uniquely placed, if I can say so myself, to write the story — I grew up in a fishing community, and knew the culture and the language. I had done PhD fieldwork right in that spot, only a couple of miles from the international airport.

AM: So clearly Newton and Wolley went to great expense to find the bird, why was it so valuable?

GP: The slaughtering on Newfoundland had a massive impact. These were small pockets of great auks, surviving on small islands and skerries along the North Atlantic. In the meantime, museums became a big thing in the British Empire and the Victorian times. Empires had to flag the flora and fauna of their colonies, and they began competing for rare animals or plants. It became an economic spiral. The harder the competition for eggs, skins, or bones, the fewer were still around, so the price would go up.

Merchants and scientists would hire fishers, typically to go and hunt for auks, but nobody realized at the time that extinction was approaching. It wasn't a thing. The peasants that Newton and Wolley spoke to, they were not speaking about the extinction, and I cannot find extinction in the 900 pages written in 1858. And yet, [the great auk] became the signature of human caused extinction. The peasants said that there was no indication that they would worry about the end of this species, they imagined that the remaining breeding population would be momentarily nesting in the Faroes and Greenland. The consensus was that the species numbers were declining and the competition was harder, but sure, there were lots of birds around.

AM: What did we think was happening to these animals before we realized extinction was a thing?

GP: I think people realized that there were swings in stock sizes. Lots of Westerners were aware of the dodo a century earlier than the great auk, and some naturalists, American and British, had spoken of disappearance of species and the role of humans. So something was brewing in the 18th and early 19th centuries.

[Previously] everyone was obsessed with species just being there permanently, as [Carl] Linnaeus had argued and [Charles] Darwin imagined, that extinction was a thing about the past, long in the historical and fossil record. Later on, people began to realize that extinction by humans was a very serious thing. Alfred Newton, as I argue in the book, deserves credit for pushing that idea.

It seems that Newton had this ability to notice things. This happened over a few years. He comes from Iceland in 1858 packed with notes, and he knows that the bird hasn't been seen in Iceland for 14 years, but still has faith that the bird is still around. But a year or two later, Newton begins to sense that it's completely gone. No one has seen it or reported it. So then he begins to become a kind of activist, establishing or joining bird protection societies. His key point is that [other] species may be increasingly disappearing in the fashion of the great auk.

I didn't quite realize this until late in my writing process, and diving again and again into the "Gare-fowl" manuscripts and Newton's writing, I finally was convinced that he was anticipating something that no one had done — namely serious extinction. He said, extinction is a processual thing and in a sense, extinction of the great auk began in Newfoundland in the 16th century. I spotted some writings of Newton in a footnote saying that the great auk was killed by humans.

Interestingly, we have genetic evidence recently supporting Newton's argument. The evidence indicates the genetic variety was sufficient enough to withstand shifts in habitat and climate. So arguably, on genetic grounds, it was clearly a human assault on the species.

AM: Is there anything that we can learn from Newton and Wooley's approach now to help save other species?

GP: Yes. I think Newton's idea of extinction as a processual thing is important. It's not something that happened with the last killing in 1844 in Iceland, it's something that takes a long time. It seems to me that scholars have been increasingly recognizing this contribution of Newton's.

AM: Obviously the great auk is gone, but what if you could bring the bird back? If you could de-extinct it, is that something that you would do?

GP: I thought a lot about it, and it would be fun. There's lots of talk about the importance of de-extinction — bringing species back to life— and it would be fun to have them around, but I think it's a waste of money. I've talked to geneticists about the complexities, and it's possible. You'd never get 100% great auk… but it's hardly worth it. Even if you manage to create one or two great auks, and they lay down a single egg, imagining that they would be able to dive back into the ecosystem and reproduce, that's a silly idea.

And that raises one of the important questions I mentioned in my book about extinction — it's a processual. A species is gone in the middle of a live world, a system, a habitat. Bringing something back into this, possibly two centuries after the last animals died, is a bit absurd and extremely complicated.

But there are all kinds of things you can do. And there are recent reports of ornithologists preventing a final collapse of species by deliberately moving them elsewhere because of habitat complications back home. That's far more meaningful than genetic reconstruction.

This interview has been condensed and lightly edited for length.

The Last of Its Kind: The Search for the Great Auk and the Discovery of Extinction by Gísli Pálsson has been shortlisted for the 2024 Royal Society Trivedi Science Book Prize, which celebrates the best popular science writing from across the globe.

In this extract from "Your Face Belongs to Us" (Simon & Schuster, 2023), journalist Kashmir Hill recalls the emergence of Clearview AI, the facial recognition technology company that burst into public consciousness with its artificial intelligence (AI) software that could supposedly identify pretty much anyone with just a single shot of their face.

In November 2019, I had just become a reporter at The New York Times when I got a tip that seemed too outrageous to be true: A mysterious company called Clearview AI claimed it could identify just about anyone based only on a snapshot of their face.

I was in a hotel room in Switzerland when I got the email, on the last international plane trip I would take for a while because I was six months pregnant. It was the end of a long day and I was tired but the email gave me a jolt. My source had unearthed a legal memo marked "Privileged & Confidential" in which a lawyer for Clearview had said that the company had scraped billions of photos from the public web, including social media sites such as Facebook, Instagram, and LinkedIn, to create a revolutionary app.

Give Clearview a photo of a random person on the street, and it would spit back all the places on the internet where it had spotted their face, potentially revealing not just their name but other personal details about their life. The company was selling this superpower to police departments around the country but trying to keep its existence a secret.

Not so long ago, automated facial recognition was a dystopian technology that most people associated only with science fiction novels or movies such as "Minority Report." Engineers first sought to make it a reality in the 1960s, attempting to program an early computer to match someone's portrait to a larger database of people's faces. In the early 2000s, police began experimenting with it to search mug shot databases for the faces of unknown criminal suspects. But the technology had largely proved disappointing. Its performance varied across race, gender, and age, and even state-of-the-art algorithms struggled to do something as simple as matching a mug shot to a grainy ATM surveillance still.

Clearview claimed to be different, touting a "98.6% accuracy rate" and an enormous collection of photos unlike anything the police had used before.

This is huge if true, I thought, as I read and reread the Clearview memo that had never been meant to be public. I had been covering privacy, and its steady erosion, for more than a decade. I often describe my beat as "the looming tech dystopia — and how we can try to avoid it," but I'd never seen such an audacious attack on anonymity before.

Privacy, a word that is notoriously hard to define, was most famously described in a Harvard Law Review article in 1890 as "the right to be let alone." The two lawyers who authored the article, Samuel D. Warren, Jr. and Louis D. Brandeis, called for the right to privacy to be protected by law, along with those other rights — to life, liberty, and private property — that had already been enshrined. They were inspired by a then-novel technology — the portable Eastman Kodak film camera, invented in 1888, which made it possible to take a camera outside a studio for "instant" photos of daily life — as well as by people like me, a meddlesome member of the press.

"Instantaneous photographs and newspaper enterprise have invaded the sacred precincts of private and domestic life," wrote Warren and Brandeis, "and numerous mechanical devices threaten to make good the prediction that 'what is whispered in the closet shall be proclaimed from the house-tops.'"

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This article is among the most famous legal essays ever written, and Louis Brandeis went on to join the Supreme Court. Yet privacy never got the kind of protection Warren and Brandeis said that it deserved. More than a century later, there is still no overarching law guaranteeing Americans control over what photos are taken of them, what is written about them, or what is done with their personal data. Meanwhile, companies based in the United States — and other countries with weak privacy laws — are creating ever more powerful and invasive technologies.

Facial recognition had been on my radar for a while. Throughout my career, at places such as Forbes and Gizmodo, I had covered major new offerings from billion-dollar companies: Facebook automatically tagging your friends in photos; Apple and Google letting people look at their phones to unlock them; digital billboards from Microsoft and Intel with cameras that detected age and gender to show passers-by appropriate ads.

I had written about the way this sometimes clunky and error-prone technology excited law enforcement and industry but terrified privacy-conscious citizens. As I digested what Clearview claimed it could do, I thought back to a federal workshop I'd attended years earlier in Washington, D.C., where industry representatives, government officials, and privacy advocates had sat down to hammer out the rules of the road.

The one thing they all agreed on was that no one should roll out an application to identify strangers. It was too dangerous, they said. A weirdo at a bar could snap your photo and within seconds know who your friends were and where you lived. It could be used to identify anti-government protesters or women who walked into Planned Parenthood clinics. It would be a weapon for harassment and intimidation. Accurate facial recognition, on the scale of hundreds of millions or billions of people, was the third rail of the technology. And now Clearview, an unknown player in the field, claimed to have built it.

I was skeptical. Startups are notorious for making grandiose claims that turn out to be snake oil. Even Steve Jobs famously faked the capabilities of the original iPhone when he first revealed it onstage in 2007.*

We tend to believe that computers have almost magical powers, that they can figure out the solution to any problem and, with enough data, eventually solve it better than humans can. So investors, customers, and the public can be tricked by outrageous claims and some digital sleight of hand by companies that aspire to do something great but aren't quite there yet.

But in this confidential legal memo, Clearview's high-profile lawyer, Paul Clement, who had been the solicitor general of the United States under President George W. Bush, claimed to have tried out the product with attorneys at his firm and "found that it returns fast and accurate search results."

Clement wrote that more than 200 law enforcement agencies were already using the tool and that he'd determined that they "do not violate the federal Constitution or relevant existing state biometric and privacy laws when using Clearview for its intended purpose." Not only were hundreds of police departments using this tech in secret, but the company had hired a fancy lawyer to reassure officers that they weren't committing a crime by doing so.

I returned to New York with an impending birth as a deadline. I had three months to get to the bottom of this story, and the deeper I dug, the stranger it got…

Concerns about facial recognition had been building for decades. And now the nebulous bogeyman had finally found its form: a small company with mysterious founders and an unfathomably large database. And none of the millions of people who made up that database had given their consent. Clearview AI represents our worst fears, but it also offers, at long last, the opportunity to confront them.

*Steve Jobs pulled a fast one, hiding the prototype iPhone's memory problems and frequent crashes by having his engineers spend countless hours on finding a "golden path"—a specific sequence of tasks the phone could do without glitching.

Your Face Belongs to Us: The Secretive Startup Dismantling Your Privacy by Kashmir Hill has been shortlisted for the 2024 Royal Society Trivedi Science Book Prize, which celebrates the best popular science writing from across the globe.

Whether the sight of an equation makes you jump for joy or run to the hills, there is no doubting that so much of science is guided by the principles laid out in these beautiful collections of symbols and numbers. But from medical testing to artificial intelligence, one mathematical rule guides much of the modern world — Bayes' theorem.

To this day, the seemingly simple equation, developed by an 18th-century Presbyterian minister and amateur mathematician, is used in modeling and forecasting to help us predict everything from future weather events, fluctuations in the stock market to the winners of sporting events.

The book "Everything is Predictable," by award-winning science writer Tom Chivers is a captivating tour of this curious theorem and how it impacts modern life, and has been shortlisted for the prestigious 2024 Royal Society Trivedi Science Book Prize. Below is a short excerpt from the book's introduction, which explores to what extent we can predict the future.

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Can you predict the future? Yes, of course you can.

You can predict with near-certain accuracy that in the next few seconds, you'll take a breath, and let it out again. Your heart will beat, somewhere between one and three times a second. Tomorrow morning, the sun will come up, at a particular time which depends upon your latitude and the time of year but which nonetheless you can find out with great accuracy. All of these events you can predict with confidence.

You can also predict that the train will arrive at a certain time, or that your friend will arrive on time at the restaurant at which you've arranged to meet her. Though, depending on the rail company, or your friend, you might be less confident in that.

And you can predict that the world's population will continue to grow until around the middle of the century, and then start to fall again. You can predict that global average surface temperatures in the year 2030 will be higher than they were in the year 1930.

The future isn't opaque. You can see into it. Some parts are more predictable than others – the Newtonian dance of the planets we can predict out for thousands of years; the Lorenzian chaos of the weather, really only a few days. But you can peer through the murk, after a fashion.

That's not what people normally mean when they say, "I can predict the future." They are referring to something mystical, some psychic or magical vision. We probably can't do that. (You'll read about a scientist in this book who thinks we can, and you’ll also read about why he's almost certainly wrong.) But we don’t need to. All that we do, all the time, is predict the future. We couldn’t function if we couldn’t. We make very basic predictions, like "the air will continue to be breathable," implicitly, with every breath we take. We make more complex predictions, like "The corner shop will have Alpen [a breakfast cereal] when I get there," each time we make a decision. We're not basing them on mystical visions, but on information we have gathered in the past.

The thing with all these predictions is that they are uncertain. The universe may or may not be deterministic; perhaps if we had perfect, God-like knowledge of the position, movement and qualities of every particle in the universe, we could perfectly predict everything, the fall of every sparrow. But we don't. Instead, we have partial information. We can see bits of the universe, imperfectly, through our imperfect senses. We have best guesses for the way those bits move — we know the human-shaped bits tend to seek food and company; we know the rock-shaped bits tend to sit still. We can make messy, imperfect predictions with that information.

Life isn’t chess, a game of perfect information, one that can in theory be "solved." It's poker, a game where you're trying to make the best decisions using the limited information you have. This book is about the equation that lets you do that.

Excerpted from "Everything is predictable: How Bayesian Statistics Explain our World." Copyright © 2024 by Tim Chivers.

It's a scene plucked from science fiction: On their deathbed, a person is completely frozen and then stashed away, so that they might be revived in the future. But could it be possible? In this excerpt from "Why We Die: The New Science of Aging and the Quest for Immortality," (Harper Collins, 2024), which was shortlisted for the prestigious 2024 Royal Society Trivedi Science Book Prize, Nobel Prize-winning biologist Venki Ramakrishnan examines the decades-long quest for cryonic preservation — in which people would be frozen at the point of death and defrosted in the future — and the pitfalls of an industry borne out of the idea.

Egyptians mummified their pharaohs so that they could arise corporeally at some point in the future for their journey in the afterworld. Surely now, a few millennia after the pharaohs and with more than a century of modern biology behind us, we would not do anything even remotely so superstitious. But in fact, there is a modern equivalent.

Biologists have long wanted to be able to freeze specimens so that they can store and use them later. This is not so straightforward because all living things are composed mostly of water. When this water freezes into ice and expands, it has the nasty habit of bursting open cells and tissues. This is partly why if you freeze fresh strawberries and thaw them, you wind up with goopy, unappetizing mush.

An entire field of biology, cryopreservation, studies how to freeze samples so that they are still viable when thawed later. It has developed useful techniques, such as how to store stem cells and other important samples in liquid nitrogen. It has figured out how to safely freeze semen from sperm donors and human embryos for in vitro fertilization treatment down the road.

Animal embryos are routinely frozen to preserve specific strains, and biologists' favorite worms can be frozen as larvae and revived. For many types of cells and tissues, cryopreservation works. It is often done by using additives such as glycerol, which allow cooling to very low temperatures without letting the water turn into ice — effectively like adding an antifreeze to the sample. In this case, the water forms a glass-like state rather than ice, and the process should be called vitrification rather than freezing (the word vitreous derives from the Latin root for glass), but even scientists casually refer to it as freezing and the specimens as frozen.

Enter cryonics, in which entire people are frozen immediately after death with the idea of defrosting them later when a cure for whatever ailed them has been found. The idea has been around a long time, but it gained traction through the work of Robert Ettinger, a college physics and math teacher from Michigan who also wrote science fiction. Ettinger had a vision of future scientists reviving these frozen bodies and not only curing whatever had ailed them but also making them young again.

In 1976 he founded the Cryonics Institute near Detroit and persuaded more than 100 people to pay $28,000 each to have their bodies preserved in liquid nitrogen in large containers. One of the first people to be frozen was his own mother, Rhea, who died in 1977. His two wives are also stored there — it is not clear exactly how happy they were to be stored next to each other or their mother-in-law for years or decades to come.

Continuing this tradition of family closeness, when Ettinger died in 2011 at age 92, he joined them. Today there are several such cryonics facilities. Another popular one, Alcor Life Extension Foundation, headquartered in Scottsdale, Arizona, charges about $200,000 for whole-body storage. How do these facilities work? Essentially, as soon as a person dies, the blood is drained and replaced with an antifreeze, and the body is then stored in liquid nitrogen. Theoretically, indefinitely.

Then there are the transhumanists who want to transcend our bodies entirely. But they don't want humanity as we know it to end before we have figured out a way to preserve our minds and consciousnesses indefinitely in some other form. In their view, intelligence and reason may be unique to human beings in the universe (or at least they see no evidence for extraterrestrial intelligence).

Related: Can minds persist when they are cut off from the world?

To them, it is of cosmic importance to preserve our consciousnesses and minds and spread them throughout the universe. After all, what is the point of the universe if there is no intelligence to appreciate it? These transhumanists are content to have only their brains frozen. This takes up less space and costs less. Moreover, it could be faster to infuse the magic antifreeze directly into the brain after death, increasing the odds of successful preservation.

The brain is the seat of memories, consciousness, and reasoning, and that is their sole concern. At some point in the future, when the technology is ripe, the information in the brain will simply be downloaded to a computer or some similar entity. That entity will possess the person's consciousness and memories and will resume "life." It won't be limited by human concerns such as the needs for food, water, oxygen, and a narrow range of temperature. We will have transcended our bodies, with the possibility of traveling anywhere in the universe.

Not surprisingly, transhumanists are generally ardent about space travel, viewing it as our only chance to escape destruction on Earth. One such proponent is business mogul and investor Elon Musk, said to be the wealthiest person in the world, depending on the year, who is well known for his desire to "die on Mars, just not on impact." Presumably one of his first goals upon reaching the red planet will be to construct a cryonics facility.

The bad news is that there is not a shred of credible evidence that human cryogenics will ever work. The potential problems are myriad. By the time a technician can infuse the body, minutes or even hours may have elapsed since the moment of death — even if the "client" moved right next to a facility in preparation.

During that time, each cell in the deceased person's body is undergoing dramatic biochemical changes due to the lack of oxygen and nutrients, so that the state of a cryogenically frozen body is not the state of a live human being. No matter, say cryo advocates: we simply must preserve the physical structure of the brain. As long as it is preserved enough that we can see the connections between all the billions of brain cells, we will be able to reconstruct the person's entire brain.

Mapping all the neurons in a brain is an emerging science called connectomics. Although it has made tremendous advances, researchers are still ironing out the kinks on flies and other tiny organisms. And we don't yet have the know-how to properly maintain a corpse brain while we wait for connectomics to catch up.

Only recently, after many years, has it been possible to preserve a mouse brain, and that requires infusing it with the embalming fluid while the mouse's heart is still beating — a process that kills the mouse. Not one of these cryonics companies has produced any evidence that its procedures preserve the human brain in a way that would allow future scientists to obtain a complete map of its neuronal connections.

Even if we could develop such a map, it would not be nearly enough to simulate a brain. The idea of each neuron as a mere transistor in a computer circuit is hopelessly naive. Much of this book has emphasized the complexity of cells.

Each cell in the brain has a constantly changing program being executed inside it, one that involves thousands of genes and proteins, and its relationship with other cells is ever shifting. Mapping the connections in the brain would be a major step forward in our understanding, but even that would be a static snapshot. It would not allow us to reconstruct the actual state of the frozen brain, let alone predict how it would "think" from that point on. It would be like trying to deduce all of the various aspects of a country and its people, and predict its future development, from a detailed road map.

I spoke to Albert Cardona, a colleague of mine at the MRC (Medical Research Council) Laboratory of Molecular Biology who is a leading expert on the connectomics of the fly brain. Albert stresses that, in addition to the practical difficulties, the brain's architecture and its very nature are shaped by its relationship to the rest of the body.

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Our brain evolved along with the rest of our body, and is constantly receiving and acting upon sensory inputs from the body. It is also not stable: new connections are added every day and pruned at night when we sleep. There are both daily and seasonal rhythms involving growth and death of neurons and this constant remodeling of the brain is poorly understood.

Moreover, a brain without a body would be a very different thing altogether. The brain is not driven solely by electrical impulses that travel through connections between neurons. It responds also to chemicals both within the brain and emanating from the rest of the body. Its motivation is driven very much by hormones, which originate in the organs, and include basic needs such as hunger but also intrinsic desires. The pleasures our brains derive are mostly of the flesh. A good meal. Climbing a mountain. Exercise. Sex. Moreover, if we wait until we age and die, we would be pickling an old, decrepit brain, not the finely tuned machine of a 25-year-old. What would be the point of preserving that brain?

Transhumanists argue that these problems can be solved with knowledge that mankind will acquire in the future. But they are basing their beliefs on the assumption that the brain is purely a computer, just different and more complex than our silicon-based machines. Of course, the brain is a computational organ, but the biological state of its neurons are as important as the connections between them in order to reconstruct its state at any given time.

In any case, there is no evidence that freezing either the body or the brain and restoring it to a living state is remotely close to viable. Even if I were one of the customers who was sold on cryonics, I would worry about the longevity of these facilities, and even the societies and countries in which they exist. America, after all, is only about 250 years old.

Excerpted from the book WHY WE DIE: The New Science of Aging and the Quest for Immortality by Venki Ramakrishnan. Copyright © 2024 by Venki Ramakrishnan. From William Morrow, an imprint of HarperCollins Publishers. Reprinted by permission.

Humans are forever venturing deep into the unknown, pushing the boundaries of our physical limits in pursuit of adventure. The next frontier for humanity is space — but just like exploring on Earth, not all expeditions go to plan. And when something does go wrong, we are faced with the same ethical dilemmas as generations of explorers before us have done.

In this excerpt from "A City on Mars: Can we settle space, should we settle space, and have we really thought this through?" (Penguin Random House, 2023), which was the winner of the prestigious 2024 Royal Society Trivedi Science Book Prize, wife and husband Kelly and Zach Weinersmith look at the terrifying situation that would have us serving up the "forbidden space meal" — other humans.

What do you do when someone dies in space? We'd love to tell you, but there's not really precedent. Death among spacefarers has always been rapid and always consumed whole crews, so there's never been a situation where a few astronauts gather round a lost companion wondering what the appropriate mode of disposal is.

The result is that, aside from informing you that if you flushed them out the airlock they should be registered as a satellite (thanks, Registration Convention!),* we can say very little.

So while we had to drop a planned section on death in space, we did get interested in a related question while researching space food: the forbidden space meal. The one option on a long Mars trip that is extremely fresh and contains precisely the nutrients a human body needs.

Related: Just 22 people are needed to colonize Mars — as long as they are the right personality type, study claims

We're just going to be real with you here — the astronautical literature on how to eat the crew is pretty limited. The reader of NASA's Human Integration Design Handbook will search for "human flesh" in vain. Apparently "human integration" is used in a narrow sense.

But we did locate a self-published paper — dare we say an overlooked classic — on the topic: "Survival Homicide in Space" by Robert A. Freitas, 1978, which may provide the needed insight. What's survival homicide? It's a situation where someone or some group can survive only by killing.

The classic example is the "Law of the Sea." The one that says you draw straws and the person who draws the short one gets eaten. Freitas doesn't mention the dinner aspect of space murder, but he does posit a scenario inspired by the novel "Marooned," in which three astronauts are trapped in a capsule without enough oxygen. Due to the precise data available to the spacefarers, they know they have enough oxygen for only two to survive until rescue comes. Logically, one should die.

And logically, we can extend the scenario to the forbidden meal by imagining your cricket herd have all died and you're running out of delicious food cubes. Can you kill one of the crew? According to Freitas, the Outer Space Treaty actually provides something of an answer. Under Article VIII, jurisdiction goes to the state of registry. Different nations have different rules regarding the "law of necessity,"** so really you just need to know what the relevant legal code permits. If you're in a Canadian ship, get a Canadian judge on the line and explain about the people-meat.

But what if you have options? Writing from 1978, this wasn't in the cards — at that time Skylab was long uncrewed and the Shuttle not yet flown. The only space crews were in Soviet ships with largely Soviet crews launched from Soviet territory.

What Freitas couldn't anticipate was the future International Space Station, which has conjoined sovereign territories from many nations. In principal you could shop around for the nation with the most cannibalism-friendly laws, but your best bet is probably to eat a fellow national inside a module owned by the nation you come from.

We don't need space cannibalism and an international incident.

Or just do nothing. In a real Mars settlement faced with a situation like in Marooned, the likeliest outcome is that you'll just die. Freitas gives a litany of times people could've prolonged their lives by ending others — in sunken submarines, collapsed coal mines, and in boats adrift. Typically, they chose to face the end together. It turns out most of us would rather die than kill.

But we did find one exception.

Professor, prolific author, and triathlete, Dr. Erik Seedhouse wrote an analysis of space cannibalism in "Survival and Sacrifice in Mars Exploration." We don't know Mr. Seedhouse personally, and he didn't respond to our email, but we will note that his book's index contains precisely one entry on "behavioral challenges," a very important topic, but five entries on the gustatory mode of crew integration.

Seedhouse asks: "Imagine you're stranded on the Red Planet with three crewmembers. You have plenty of life-support consumables but only sufficient food to last one person until the rescue party arrives. What do you do?... One day, while brewing coffee for breakfast, you realize there are three chunks of protein-packed meat living right next to you."

He argues that the largest people should sacrifice themselves first, since they both consume and provide the most food. We don't know where Seedhouse would fall in the buffet line because we couldn't find his height and weight online, and honestly we're scared to ask.

Mostly because his book includes a weirdly detailed look at how to butcher Homo sapiens. Also, on page 144, the reader will find a photo of ten astronauts floating happily in space, with the caption: "In the wrong circumstances, a spacecraft is a platform full of hungry people surrounded by temptation. Is it wrong to waste such a neatly packaged meal?"

That is, as they say, a question for philosophers. But we do have one pragmatic piece of advice for any potential Mars settler: Leave Erik Seedhouse at home.

*Though they probably wouldn't be a satellite for long. In Terry Virts's memoir, he notes that if you had to have this sort of "burial at sea," astronauts would likely direct their deceased crewmate's remains toward the Earth, so they'd burn up in the atmosphere in the not-too-distant future.

**We elected not to get too in the weeds about exactly what the standards are, but for the future law students in the audience, the two most relevant cases are Regina v. Dudley and Stevens as well as United States v. Holmes. We've been told these are both used to trick law students into thinking law school will be interesting.

An excerpt from A City On Mars: Can We Settle Space, Should We Settle Space, and Have We Really Thought This Through? by Kelly and Zach Weinersmith, published by Penguin Press, an imprint of Penguin Publishing Group, a division of Penguin Random House, LLC. Copyright © 2023 by Kelly Weinersmith and Zach Weinersmith.