The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction

by Henry Gee

From the winner of the 2022 Royal Society Science Book Prize, a thrilling and thought-provoking account of the rise and fall of humankind.

For the first time in over ten millennia, the rate of human population growth is slowing down. The global population is forecast to begin declining in the second half of this century, and in 10,000 years’ time our species will likely be extinct.

In The Decline and Fall of the Human Empire, Henry Gee shows how we arrived at this crucial moment in history, beginning his story deep in the palaeolithic past and charting our dramatic rise from one species of human among many to the most dominant animal to ever live on Earth.

But rapid climate change, a stagnating global economy, falling birth rates and an unexplainable decline in average human sperm count are combining to make our chances for longevity increasingly slim. There could be a way forward, but the launch window is narrow ...

Drawing on a dazzling array of the latest scientific research, Gee tells the extraordinary story of humanity with characteristic warmth and wit, and suggests how our exceptional species might avoid its tragic fate.

Genres: Science, Nonfiction, History, Evolution, Anthropology, Climate Change, Audiobook

279 pages, Hardcover

First published March 13, 2025

About the author

Henry Gee's next book The Wonder of Life on earth, illustrated by Raxenne Maniquiz, is out on 5 February 2026. His other books include The Decline and Fall of the Human Empire, A (Very) Short History of Life on Earth (winner of the 2022 Royal Society Science Book Prize) and The Science of Middle earth. His books have been translated into more than 25 languages. He is represented by Jill Grinberg Literary Management and lives in Cromer, England.

Reviews

[Brian Clegg · Rating 4 out of 5]

In his last book, Henry Gee impressed with his A (Very) Short History of Life on Earth - this time he zooms in on one very specific aspect of life on Earth - humans - and gives us not just a history, but a prediction of the future - our extinction. The book starts with an entertaining prologue, to an extent bemoaning our obsession with dinosaurs, a story that leads, inexorably towards extinction. This is a fate, Gee points out, that will occur for every species, including our own.

We then cover three potential stages of the rise and fall of humanity (the book's title is purposely modelled on Gibbon) - Rise, Fall and Escape. Gee's speciality is palaeontology and in the first section he takes us back to explore as much as we can know from the extremely patchy fossil record of the origins of the human family, the genus Homo and the eventual dominance of Homo sapiens, pushing out any remaining members of other closely related species.

As we move onto the Fall section, Gee gives us a strangely mixed picture of both success - rising from small numbers to our current around eight billion and dominating much of the globe - and failure. Agriculture, for example, enabled the explosion in population but also made for a non-ideal diet and lifestyle. (It's arguable, though, that without it we wouldn't have science, for example, which perhaps is worth those issues.) It seems that, for a number of reasons in the way we developed, our species is particular susceptible to disease. But the negatives have, so far, largely been countered by our ingenuity - meaning that despite everything ranged against us, humans today are living longer and better lives than we ever did as hunter gatherers.

This success, though, Gee tells us, still leaves us on the brink of a collapse. After reaching a peak, population is expected to shrink - he worries that this will reduce our pool of potential genius, meaning we may not be able to continue the technological solutions that have kept us going to date. Climate change and resource scarcity add to the potential to reduce our numbers to the extent that our species' inevitable extinction looms closer.

The final section, Escape, is where Gee presents his solution to decline. This, I'd suggest is the weakest part of the book. Venturing into space is seen as the only way forward (like me, Gee is a science fiction aficionado) - I find it hard to believe that there aren't other, less dramatic, potential technological patches that could be applied. While I don't doubt our eventual extinction, I also think that (unless brought on by something like nuclear war, which isn't mentioned) we are more capable of manipulating our environment here on Earth for survival than Gee gives us credit, making the end perhaps further away than is suggested. And manipulating Earth's environment will always be far easier than starting from scratch in space, where there are so many other obstacles to be overcome.

This remains a very thought-provoking book that is highly engaging. Despite his academic origins, Gee writes with a light touch that sometimes feels more like a chat in the pub than reading a popular science title. We have a tendency as a species to assume that we'll always be here - but clearly we won't. The reality is sometimes stark, but always interesting.

[Henk · Rating 4 out of 5]

Very thought-provoking take on how humanity developed as a species, what it's current trajectory is and how the future could look like. Although I find the solution proposed for our conundrum unconvincing (let's go to space!), the book is written in a very accessible manner.
The answer is that humans will perish, along with everything else.

Taking a long view, Henry Gee covers how humanity rose as dominant species. This historical section resonated most with me and made me think of Sapiens: A Brief History of Humankind, with thought provoking takes on how we transitioned from hunter gatherers to farmers. In general The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction is loosely inspired by the Rise and Fall of the Roman Empire of Gibson. The section on our current unprecedented decrease of the global population, reflecting a combination of economic worries, emancipation, dropping sperm counts due to environmental influences, societal change and climate change induced stresses, was good as well, even though it read at times as extended Financial Times/Economist article.

The final section was definitely weakest, pivoting to living in asteroids and gene editing to bring about a new frontier for the species. Maybe this is the boldness we need as a species, but I found it unconvincing and techno-utopian. Also the whole concept of more humans equals more progress feels logical but if we look back at how we were able to figure out scientific concepts like gravity, chemistry and evolution, to name just a few, with less than a billion humans makes the argument feel weaker. I guess my main unanswered question is how 1 billion humans (prognosis for 2300) unsustainable from an evolutionary perspective, given at the time of Napoleon we were at the same number and the species even survived at just a few thousand breeding individuals?

An interesting read that allows us to do something no other species can do, namely zoom out and reflect on our longevity.

Observations and quotes:
There is more genetic diversity in a clan of chimpanzees than in the whole of humanity

Wherever homo sapiens went, destruction followed

Population growth peaking in the 1960s

Going into space? I would think that gene editing would be a more logical route towards human evolution.

The clock is ticking for our species, with our time left being estimated below 10.000 years by the author, very short in a geological timescale, for Homo Sapiens to change

Lucy dying from falling out of a tree

No other mammals are fully bipedal

Pelvis being narrow (for better locomotion) versus being wider to ensure easier giving birth remains a significant battle during evolution of humans

Humans initially evolved as endurance runners, slower but more tenacious than the wild they hunted in groups.

More than half of modern day Pakistani marriages being between second cousins removed or closer

Humans, pre-agricultural revolution, were always rare

2% of non-African human DNA is attributable to Neanderthals

Newton = 500 million people
Einstein = 1.6 billion people

Technology progressing incredibly slow when human population were living in small, unconnected communities

Increasing evidence that agriculture rose as Homo Sapiens wiped out most of the wildlife heavier than 40kg

Humans only domesticated 14 animal species, yet of the 200+ known diseases that humans suffer from, over 100 are related to animals we domesticated

Farmers being sicker due to higher population density and zoonoses, and lower food variety

Bananas being genetically clones and super susceptible to blights

Inbreeding increases risks of relatively rare diseases

Human diversity being limited by near extinction events in the history of the species

1.280 breeding humans for millennia at the bottleneck of history, explaining a lack in genetic variety in our species. It is interesting to consider if we were more diverse what the world would look like.

Chimpanzees only suffering from a few indigenous diseases

The world supporting c. 10 million people when we were hunter gatherers

From 1960 for the first time Homo Sapiens population growth started to decrease

23 countries forecast to half their population in 2100 at current replacement rates

Didn’t know the Watersnoodsramp was a thing in England as well

Unknown reason of decreasing sperm count across the world

Mammalian species in general have a lifespan of no more than 1 or 2 million years

Habitat destruction even leads to extinction of dominant species, with degradation of habitat leading to the emergence of competing, more efficient species in the degraded habitat

An estimated 25-40% of the products of all photosynthesis on earth is sequestered by humans

Increase of rice production by 36% per acre in the 70s, but only 7% after the effects of the Green Revolution

Gene editing to produce more effective photosynthesis

RuBisCO enzyme leads to loss of at least 50% of energy gained by plants from catching sunlight, while being the most abundant enzyme in the world. Evolved in a planet that had much lower carbon levels than currently and with a less bright sun (with plants not being able to absorb over 90% of energy gained from the midday sun)

Maximum current photosynthetic efficiency in plants estimated at 8%

Since 1980 tree cover grew by 9 times the UK in predominantly in temperate regions, while the biologically most diverse habitats like rain and cloud forests decreasing significantly

Rabbits being introduced to the UK by the Romans

Pristine landscapes simply don’t exist

Our species has defined itself and found success by passing into new habitats, now space as a new frontier

Already our cities are completely humanly constructed

Biosphere 2 failed due to growth of bacteria, stable biomes being incredibly hard to create

6 out of 10 robotised missions to Mars being unsuccessful

Living in astroids - I am very doubtful about this solution

There are therefore no rational reasons for anyone to settle in space - I agree, maybe lets focus on taking better care of the planet instead of focusing on a tech utopia in space for evolutionary purposes

[Elentarri · Rating 2 out of 5]

Henry Gee came up with a nifty title, some vague but old ideas, and then wrote a book with contents and style that is uninspired, repetitive, lacklustre, and muddled. This book is not nearly as entertaining or informative as his previous books. It also doesn't cover any new ground. Human evolution, extinction in general, the demise of the human species, and human population decline are not new. Not keeping your eggs (or all your humans) in one basket is also not a novel concept. Gee covers the progress of humanity is three stages - Rise, Fall and Escape. The Rise portion of the book provides a superficial summary of what is known about human evolution. According to Gee, the pinnacle of human evolution was when just before all the other hominid species went extinct. Since humans no longer have a species with similar capabilities to compete against, it's all downhill from here. The Fall portion of the book breezes through a selected few factors detrimental to human existence: diminishing resources, low genetic variation, habitat degradation, stagnating economy, changing environment, disease and declining fertility that are setting homo sapiens up for collapse. The author practically ignores any other detrimental factors, such as nuclear war or another asteroid impact. The third aspect of this book involves Gee's fuzzy attempt at explaining how humans can escape this inevitable extinction by spreading out - into space (while somehow ignoring the 'founder effect' he mentioned a few chapters previously). The book, also, does not include one illustration, diagram, chart, or map. Henry Gee has a point, but this book is neither well written, nor the argument well thought out. This book is the author's half-hearted attempt to elaborate on THIS short article. Read the article, skip the book. Thoroughly disappointing.

[EmJ · Rating 4 out of 5]

Don't let the doom and gloom title of this book deter you from reading it. The author traces the history of how humanity came to be in it's present form and explores possible futures for our species. While extinction is an obvious possibility, the author also takes time to show how humanity might be able to push off that fate. While this book is very heavily science based, the author writes in such a way that everything was easy to understand. My only complaint is that sometimes the author is a little bit repetitive. Overall I found this book interesting and thought provoking.
Thank you to the author, publisher, and NetGalley for the ARC in exchange for my honest review.

[G Flores · Rating 4 out of 5]

Mankind certainly does love thinking about how it will die almost as much as it loves figuring out how to live forever doesn't it? Gee channels both impulses into this pithy volume with a certain effortlessness that keeps the humor from diluting the information and keeps the information from depressing the hell out of you. It's an interesting line to walk and it is done rather deftly.

Unfortunately, there's not much more to say than that which is why I can't give it that fifth star. It is enjoyable, informative, doesn't overstay its welcome and moves along at a brisk pace. It's an excellent non-fiction palette cleanser if you've just read something very heavy and need something light but feel a need for something at least slightly informative.

Thank you to Net Galley for an advanced reading copy of this book to be published March 18th, 2025 at time of writing.

[Logan Kedzie · Rating 1 out of 5]

The Rise and Fall of the Human Race is about the end of humanity. Not in the sense of a catalog, or as a prediction, but in a statistical or ecological (in the formal sense of the word) sense. If we take what we know about extinction as a process, and direct that analysis towards humans, what do we come up with?

The discussion of extinction science is the highlight of the book. The key observation is that the usual methods of looking at the end is wrong. Someone talking about existential risk has a risk in mind, and usually solution at a reasonable cost, but extinction is not about an extinction event as much as it is being in a state of vulnerability to extinction. This puts humans with a small amount of time, geologically speaking, like 10K years.

The writing is delightful. I want to go drinking with the author. The endnotes are frequently hilarious. The book is an introduction to great concepts like extinction debt. This is a book where the brevity is a problem. I wanted more writing and more detail on more things, and there are plenty of places for the author to expand.

Well, maybe. This book is an expansion of an article that the author wrote. Most of the best parts are shared with that article; the rest is the book-lentgh version of the difference between science and the humanities, sometimes memed as the difference between a high INT stat and an high WIS stat.

The author's solution to preventing humanity's extinction is for humans to expand into space. The reason this is the solution is a tautology: humans should go into space because they should go into space. Humanity will outstrip the carrying capacity of the earth, and the way to fix that is to go into space, which will require vastly expanding the carrying capacity of the earth, based on what will be required to support people living in space. Gay Space Communism is unexplored.

This might be an idle problem. The book could pass as a polemic with a few more expletives and polemics grade on their own curve. I share with the author the view that Ehrlich deserves contempt, but less than he gets*. It becomes a real issue because of the various fragments of argumentation in the book that feel like no one is minding the till.

The author posits our future as a vegan matriarchy on the basis of efficiency (rather than a fetish comic), that animals products are an inefficient way of getting calories and that the potential of women's contributions to society are historically untapped and must be in order for humanity to survive. However, this comes up in the context of solving the problem of food via artificial photosynthesis, which okay, cool, but at that point, you might as well just posit a cheesburger tree.

Similarly, the need for action now is due to the demographic cliff and its knock-on effects on human ingenuity and resources: the most people provides us with the most chance of having people who can solve the problem, and having too few people presents a possibility where there aren't enough people to provide the surplus necessary to allow people to investigate those problems as opposed to toil in the fields. The cause of this is multi-variable, but one elaborated on is 'female emancipation.'

That sound you are hearing is a thousand conservative influencers readying their keyboards.

A blanket statement of women had no rights, and now they do, deserves scrutiny. Technically correct it becomes an oversimplification to the point of misleading. Similarly, the expression of the crucial role of women in solving the problem is so causally engaged and unsupported that it achieves vaulted technically correct status.

A lot of the statements about history deserves scrutiny. The author accepts the 'own goal' view of Rapa Nui, sending the critics to an endnote. The author presents both The Great Hunger and 1995 Chicago in purely environmental terms. Neither are. Both are more in line with the author's extinction thesis, where the catastrophic event is ancillary to the systemic failure. People died en mass because of policy, not because of reality.

To that end, the book's conceit operates in a sort of twilight zone around Edward Gibbon. Yeah, it is what he wrote, but devoid of context before or hence, either of what Gibbon was doing or the way that the idea of decline, its uses, abuses, and intellectual or ideological history. This is no huge complaint, but it does start to feel like horseshoe theory on the wooification of science.

Oh, and it plays fast and loose with the science. I am not going to violate the terms of the ARC by a full quotation, but in the discussion of the concept of an evolutionary bottleneck applying to humans, the author raises the idea, notes that it is currently disfavored, and then uses it anyway on the basis that it is true "poetically."

Poetically true science? Is this like Justice Roberts' court of public opinion as regards Korematsu?

I get the core of the author's point. Humans, particularly in their status as the water sprouts on the otherwise dead branch of homo, exist in a sort of genetic risk that does not apply to other species. So why not eugenics? You cannot say eugenics does not work. We've established that the poetic truth of science is the important bit. Every bit of the argument here works for eugenics. It works better in fact. No need to worry about radiation's effect on developing children if we just kill the diabetics and autistics. Sure, they did not do it right before, (though I am certain you could find some human biodiversity folks to claim that they actually did), but this time it will be different.

Did any science fiction author read this manuscript?

In closing, I return to the tautology problem. The only reason that I can see that space travel was chosen is because extra-planetary living is "in" with the existential risk crowd. The same people looking to sell timeshares on the Moon are the most vocal about the author's concerns (and usually trying to get you to use crypto). But as far as I am concerned, the author has as good an explanation for why space will not save us. If the bottlenecks from founder effects are bad on earth, think how much worse space will be.

I loved the writing, and I loved the science. I now have a whole new scientific sub-discipline that I am interested in learning about. But - unintentionally - the author has written a pitch sheet for Bond villains.

My thanks to the author, Henry Gee, for writing the book, and to the publisher, St. Martin's Press, for making the ARC available to me.

* - There is a sidebar here that I may return to via blog about the author's use of The Population Bomb in general.

[Anshuman Swain · Rating 3 out of 5]

3.5 rounded down to 3.

A really interesting premise for a book - the extinction and survival of humans. Although the book was well thought out in overall structure, the text was a bit repetitive and some parts were less well researched than others.

Overall, I felt that the length of the book could have been definitely shorter (The author mentions that this book grew out of an essay he wrote in a magazine, and maybe a length somewhere in between would have been nice).

[Cindy · Rating 4 out of 5]

Homo Sapiens have at most 10,000 years left as a species unless we take to the stars. So asserts Henry Gee. Every chapter in this book starts with a quote from “The Rise and Fall of the Roman Empire” and Gee draws compelling parallels from then to now.
He talks about isolated societies, a lack of genetic diversity, and how humans are more susceptible to disease than any other species on the planet because of our relatively small gene pool. Should our infrastructures fail and people become isolated again in small groups, it won’t be long (in evolutionary terms) before we die out. Yet, he admits that if/when we go to the stars, we will still have our limited gene pool with which to contend. Lots of food for thought presented clearly and almost breezily. The audiobook is well narrated.
My thanks to the author, publisher, @MacmillanAudio, and #NetGalley for early access to the audiobook for review purposes. Publication date: 18 March 2025.

[EmG ReadsDaily · Rating 4 out of 5]

Interesting and thought-provoking.

My nerdy brain really enjoyed this exploration or the rise and fall of humankind. As an added bonus, the audiobook is narrated by the author.

[Heather · Rating 4 out of 5]

Well, this wasn’t exactly an uplifting read, but I suppose it wasn’t meant to be. The Decline and Fall of the Human Empire paints a grim picture of our future, arguing that despite the Green Revolution of the 1960s, humanity is on a slow but inevitable path to extinction within 10,000 years—unless we act within the next two decades.

Gee lays out factors driving this decline, from plummeting sperm counts to economic instability leading people to have fewer children. He also highlights threats like reliance on singleton crops, mass migration sparking conflict, and even the effects of women's rights and increased access to education on population trends (a point sure to spark debate). While some arguments felt more compelling than others, the overall message was clear: if we don’t act soon, we may be sealing our own fate.

His proposed solutions are just as bold as his warnings. He argues that we need to stop eating meat entirely, eat plants directly instead of filtering them through animals, develop artificial photosynthesis, convert waste into food, and colonize space to ensure humanity’s survival. While I learned a lot about human genetics and the Founder Effect, devoting an entire chapter to photosynthesis felt excessive, and at times, he was a bit repetitive in making his points. Some arguments could have been more concise without losing their impact.

One of the most surprising takeaways was that our global population is now declining. While that might sound positive, Gee argues that it takes billions of people to produce the next Einstein or Newton—the minds that propel humanity forward. A shrinking population, he suggests, may stall our progress.

Though bleak, the book was undeniably thought-provoking. Whether you find it alarmist or a necessary wake-up call, The Decline and Fall of the Human Empire is a fascinating, if unsettling, look at our species' potential downfall.

ARC was provided by the publisher via NetGalley in exchange for an honest review.

[Lissa00 · Rating 3 out of 5]

I thought the first half of this book was stronger than the second. I don’t think this book sold me on the decrease in population necessitating a move to living in space. This is well written and interesting but I don’t feel sold on space colonization being the best option to solve the problem of population decline. I received a complimentary digital copy of this book through NetGalley.

[Gus · Rating 2 out of 5]

A (Very) Short History of Life on Earth: 4.6 Billion Years in 12 Pithy Chapters was my favorite science read in 2023. It was brilliantly written; concise enough not to make you feel like you're reading a textbook and wonderfully paced, building up to a poetic conclusion: the end of all life on earth, a billion years from now.

Naturally, I was excited when I saw Henry Gee had just published a new book, this time about the extinction of our species. However, it was a disappointing read. I think the author overshot his mark. The book feels unfocused and like there was not enough content (This was made evident to me at the end when he mentions that the book was born out of an article he wrote).

The main thesis of the book is that, from a biological point of view, once a species dominates its ecosystem or becomes too successful, it is fated to extinction. This naturally applies to us. We're currently at an inflexion point: the only way to guarantee our existence is to colonize space, and, as the birth rates keep falling all across the world, we only have a small window of time in which there's still enough humans that could make this future possible, before our population size sharply declines. The reason being that such a level of innovation can only happen with high population sizes.

The problem is, I don't buy his conclusion. The foundations are solid: humans have so little genetic variety compared to our ape cousins that we are one virus or bacteria away from the next pandemic that could wipe out half of our species. We depend on such a handful of crops (wheat, rice, maize, etc.) that, again, we're a couple of crop diseases away from a global famine. And then there's climate change.

Concluding, however, that the only option left is to go to space, when we are not even able to live on an underwater colony, is to indulge in the out-of-touch, misanthropic escape fantasies of the hyper-rich.

The elephant in the room is --who would've thought-- capitalism. There is not a single mention of the economic forces and the powers at play driving the demise of our planet. Unlike his previous book, you can't really talk about the possibility of our extinction without getting into the politics that shape our lives. This is the book's fatal flaw. It could have used a co-author to complement this part.

It was still a decent read: I learned quite a few things, but the pace is all over the place. The book abruptly ends just when it starts talking about space, and this is the point it's building up to. There are also a few of mentions of Jared Diamond, including the already debunked, oft-repeated theory that the Rapa Nui destroyed their habitat due to their short-sightedness. This casts more doubt on the quality of the author's research.

To summarize, it's a book with great bits of knowledge, but take its conclusion with a grain of salt. It feels tone-deaf for the times we live in.

There is no planet B.

[Rob Sedgwick · Rating 4 out of 5]

This is a rather downbeat book that argues that declining populations at the end of the century will see us pass our peak as a species, decline, and eventually go extinct in the far future. Writing about the future always produces a giggle when it actually arrives, as it is usually way off the mark (e.g. Ehrlich's oft-cited The Population Bomb, which is often mentioned in these pages).

This book's basic premise is that a relatively small genetic "founder" pool left humans vulnerable to being eradicated. We are all supposedly descended from a very small group of Africans, with some minimal interbreeding with other types of human, now extinct. Our "peak" was just before the invention of agriculture - it's been downhill ever since.

The author makes much of how extinction is "normal" and over 99% of all time species are now extinct. There are so many of us, though, that even if 99.9% of us died, there would still be 8 million people left, far more than most other mammals. Total extinction is hard to imagine, even if we were reduced to a small number of individuals (who would be able to happily breed away). We are also unique in being aware that we even are a species that can become extinct, which leads us to the second part of the book - human ingenuity.

Here, the tone shifts. The author unsurprisingly looks towards space as a way of arresting our otherwise imminent decline. Space will be a tough nut to crack, but it's inevitable in the aeons left to however many of us there are at any one time. Even if civilisation ends, there's plenty of time and resources to begin again, maybe many times over. So I am not sure I agree with the book's thesis, and given the inevitability of people living elsewhere in the solar system and beyond, I don't really see the solution to "his" problem as a solution - just something that would happen anyway. Give it a few centuries, and we'll see who is right.

[Jenn · Rating 3 out of 5]

In The Decline and Fall of the Human Empire, author Henry Gee explores humanity's evolutionary rise and the factors contributing to its potential downfall. Drawing on both human evolution and examples of past extinctions, Gee builds a compelling case that our species is on a path toward extinction. He also outlines possible actions we could take to change course, though these are not explored in as much depth as I hoped.

As someone who enjoys paleontology more than anthropology, I was pleasantly surprised by how engaging I found the archaeological and historical elements of the book. Gee presents a fascinating look at the traits and circumstances that led to humanity's dominance—many of which, ironically, now threaten our survival. I found the statistical analysis behind his estimated timeline for humanity's decline particularly compelling. However, I would have appreciated a more thorough discussion of the solutions he proposes to avert this outcome.

I recommend this book to anyone interested in a short but interesting look at humanity, with a dire warning that isn't overly negative.

3.5 stars, rounded down.

Thank you to St. Martin's Press and NetGalley for the copy of the eARC in exchange for an honest review.

[Zoe · Rating 2 out of 5]

Quite duplicative across the three sections. At times, overly technical (e.g. photosynthesis systems) and over reliance on space travel/existence as the resolution to prevent extinction.

[Kara · Rating 4 out of 5]

A compelling look at the history of ancient humans up through modern homo sapiens, who Gee argues are on a path to extinction (in the next 10,000 years) unless we find a way to our next frontier, space.

Thank you to Macmillan for an ARC in exchange for a fair and honest review.

[Neil Fox · Rating 1 out of 5]

Henry Gee’s central thesis is that Homo Sapiens is destined for ultimate extinction, that we are living on borrowed time on the verge of collapse (relatively speaking, of course; our extinction will occur in the next 10,000 years or so) and that Homo sapiens will wink out of existence much as the Neanderthals did before us. He then theorizes that we have a narrow window of opportunity to avoid this fate.

Gee argues that human population is on the cusp of a steep decline. World population will go into reverse sometime toward the end of this century after first continuing to grow albeit at a declining rate of growth, and in the process further placing unsustainable pressure on our planet’s resources as it does.

He presents a sort of anti-Malthusian scenario, driven by factors such as the emancipation of women (ie: fewer babies), mysteriously falling sperm counts and certain genetic factors. Gee is not alone in his beliefs - a certain Elon Musk is apparently obsessed with population decline - and his his remedies to avoid this fate are bordering on the ludicrous. He advocates taking control of photosynthesis to spark a new ‘green revolution’ in food productivity, and the colonization of space, including living in, erm, hollowed out meteors. Right. These are wishy washy things at best, with echoes of Yuval Noah Harari’s writings that mankind will save itself by re-engineering ourselves into a Godlike form of superhuman immortals. Gee though simply doesn’t have the intellectual power or punch of Harari; this has the feeling of a book-length essay to it. He fails to dwell on what could make us extinct even quicker- catastrophic climate events, a new deadly pandemic, nuclear Armageddon, AI run amok or some other technological calamity.

[Anna · Rating 2 out of 5]

interesting bits about history, but wtf with the wet dreams of colonizing space with humans… that dragged the rating down by at least 2 stars

[Dan · Rating 4 out of 5]

My thanks to NetGalley and St. Martin's Press for an advance copy of this book that looks at the how the human race made it to the top as a species, the problems that humans are facing and how these lead to our inevitable extinction.

Something humans have a hard time admitting to themselves and others, besides being wrong, is that everything ends. This review, the book being reviewed, the reader the author, everyone we know, or will ever know. At some point they will be gone,as will the whole of humanity. In many ways we seem to be in a race to end it all, with a feeling that something better awaits on the other side of the veil. I have my doubts, but I have always had a sense of my own mortality. Everything ends, that's a universal truth. How soon that happens might just be up to us, and the way things are going right now, that end might be zipping fast. However as the author points out, there are things we can start doing, though again looking at the state of the world, co-operation seems the furthest from anyone's mind. The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction by Henry Gee is a look at how humans defied the numerous odds and made it to the pinnacle of power on Earth, how what goes up must come down, and what we might be able to do to delay the end, or even expand the reach of humanity to the stars.

The book begins with of course the dinosaurs. There were numerous ideas on why the dinosaurs went extinct, theories that covered a whole lot of bases. Some thought the eggs of dinosaurs were too soft to protect the babies, or became too hard to babies to get out of. Maybe mammals ate the eggs. Or even a plague or galactic event, say something from the sky. What became apparent, was that many species had risen to the top and eventually went extinct. Gee looks at these reasons and shows where humans nearly didn't make it, and how these events helped or hindered the growth of humans. Gee looks at the problems facing humans today, and points climate change that will force migration as areas become too hot, or too underwater to support life. More importantly Gee discusses the fact that people are not having children, either by choice, or by fertility problems. This will cause problems for a lot of countries, as population age out of existence, and no one will be there to do the work needed to keep GDP up, or to advance technology. Especially in these days of racial discrimination. Gee posits a few ideas, changes in how we farm and produce food, worldwide female emancipation, something the Internet trolls won't like, and of course space being the place where humans might have to go.

A book that is full of so much information, however all told in a way that is not a lecture or a droneing teacher, but told in a conversational style. There is a lot here that will spark a few, actually many spirited conversations. And saying that space and life on Mars might help humans seems a little tech bro solution to ignoring problems on Earth. However Gee states his case quite well, and makes a very good argument. I just think that humans have regressed in many ways in their attitudes towards women and minorities, and don't see how in this current environment any of this could gain traction. The book is well-written, and well-thought out, with a good mix of hard science, with plenty of explanation. And a lot of hope.

As I stated a book that a lot of people won't like, it talks about female rights, climate change, and evolution. I found this quite engaging, and learned quite a bit about the way humans adapted to things, and found myself almost rooting for humanity to keep going. Something I have not felt in a while. Definitely a conversation starter, and a book that will be of interest to a lot of people.

[Sarah Jensen]

Book Review: The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction by Henry Gee

In The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction, Henry Gee presents a powerful and provocative exploration of humanity’s precarious position on this planet. Through a blend of historical analysis, scientific inquiry, and philosophical reflection, Gee argues that human beings are not only at risk of extinction but are also confronting a self-inflicted crisis driven by environmental degradation, social inequities, and technological hubris. This book is an urgent call to understand the patterns of our past and their implications for the future of humanity.

Content Overview
Gee’s book is structured as a narrative that intertwines evolutionary biology, history, and current sociopolitical dynamics. He begins by outlining the historical context of human development, detailing the evolutionary pressures that shaped our species. He provides a thorough examination of how these historical trends have contributed to the current challenges we face, including climate change, resource depletion, and societal fragmentation.

The book is divided into thematic sections that address various aspects of human existence, such as technological advancement, environmental impact, and cultural evolution. Each section builds upon the last, creating a cohesive argument that illustrates the interconnectedness of these issues and how they contribute to humanity’s decline.

Thematic Exploration
Several key themes emerge throughout The Decline and Fall of the Human Empire:

Historical Context of Human Evolution: Gee emphasizes the importance of understanding our evolutionary history as a means of interpreting current behaviors and societal structures. He argues that the traits that once ensured survival, such as cooperation and adaptability, are increasingly at odds with modern challenges.

Environmental Consequences: A significant portion of the book is dedicated to examining the environmental degradation resulting from human activity. Gee highlights the unsustainable practices that threaten biodiversity and the ecological systems that humanity relies upon, urging readers to recognize the urgency of environmental stewardship.

Technological Hubris: Gee critiques the blind faith in technology as a panacea for human problems. He discusses how technological advances can exacerbate existing issues rather than solve them, often leading to unforeseen consequences that amplify our vulnerabilities.

Social Inequality: The author addresses the impact of social and economic inequalities on our collective future. He argues that disparities in wealth and access to resources undermine societal cohesion and hinder efforts to address pressing global challenges.

Philosophical Reflection on Extinction: Amidst the dire warnings, Gee engages with philosophical questions surrounding extinction. He contemplates what it means to be human in the face of potential demise and reflects on the legacy we leave behind.

Style and Accessibility
Gee’s writing is engaging, often poetic, and filled with vivid imagery that brings complex scientific concepts to life. He adeptly balances accessible language with scholarly rigor, making the book suitable for both academic audiences and general readers interested in the intersections of science, history, and philosophy. His use of anecdotes and examples serves to illuminate abstract concepts, fostering a deeper understanding of humanity’s plight.

Practical Implications
The Decline and Fall of the Human Empire is not only a work of observation but also serves as a call to action. Gee emphasizes the necessity for individuals, communities, and governments to rethink their practices and prioritize sustainability, equity, and resilience. The book encourages readers to engage in critical conversations about the future of humanity and the steps needed to avert catastrophe.

Conclusion
Henry Gee’s The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction is a thought-provoking exploration of the existential crises facing humanity. By weaving together historical context, scientific insights, and philosophical reflections, Gee compels readers to confront uncomfortable truths about our collective future. This book is an essential contribution to the discourse on human survival, offering a bold vision of what is at stake and urging us to act before it is too late. As the world grapples with unprecedented challenges, Gee’s work serves as both a warning and an invitation to reimagine our relationship with the planet and each other.

[Socraticgadfly · Rating 3 out of 5]

3.25 stars overall.

First, I liked the riffing on Gibbon and I don't think it was overdone. (He has a quote at the start of each chapter, as well as the title.)

The first two-thirds of this short book were decent on the evolutionary history of Homo sapiens. Not much new, if you read much on hominin evolution, but, the issue of evolutionary bottlenecks is key.

Even more key is the issue of "extinction debt," also mentioned in this Scientific American article by Gee which became the starting point for this book. The basic idea is that a "tipping point" for the eventual extinction of a species may be hit before it's known. In ecology, that's used by humans about other species that we may have forced into irreversible bottlenecks without knowing it at the time. But, per Gee, we may do it to ourselves, too. Or may already have.

The last one-third starts to slip more and more, with the first additional mention of something hinted at in the prologue — the idea that our salvation is through colonizing space.

Not.Even.Wrong, per Wolfgang Pauli.

First, per social psychology, the "wherever you go, there you are," will apply in spades. The same resource overextraction, greed, etc. — and also the lack of evolutionary competition he says is one issue that will hasten the extinction of H. sapiens on earth — will all be there on Mars, Planet 4 of Proxima Centauri, etc.

Second, for talking about evolutionary bottlenecks and inbreeding, whether in Neanderthals or Spanish Hapsburgs, he simply doesn't give it a thought for a Mars colony. Sure, Elmo Musk would love to have a Dr. Strangelove version of Mars caves, but that would only go so far in solving inbreeding.

(And, besides surface solar radiation on Mars, who knows what else on the Red Planet will reduce the fertility of human nads and ovaries?)

As part of this last portion, Gee mentions "A City on Mars" by Zach and Kelly Weinersmith but apparently didn't learn a thing from them, because, the next to last graf of my review of that book says:

Finally, they note that colonizing either place will NOT in all likelihood improve humanity. They don't utter it, but the "wherever you go, there you are" applies to humans as a species as well as individuals. If we really wanted to improve, we'd do it right here.

Henry, did you not get that? I even used "that" same phrase.

In short, he knows, in a 4-star plus first two-thirds, that we're likely greatly hastening our own extinction, then throws a quasi-utopian Hail Mary.

I'd like to go higher to offset all four 1's and 2's more, but can't do it. All have problems. Briefly? I don't think he's derivative of Diamond, Harari or the like, nor do I have problems, obviously, with his riffing on Gibbon. Per the link to his original article, he thinks the possibility of nuclear annihilation has diminished enough he doesn't mention it here. His handling of Ehrlich is nuanced. And, it has a generally unified theme.

This book would have been much better if Gee had channeled his inner secularist paleontologist Unanumo and simply accepted "The Tragic Sense of Extinction-Bound Life" and gone on from there.

[Tony Lawrence]

The title and chapter comes from the famous book about the Roman Empire, Gee draw parallels with the state of Homo Sapiens, which is a bit contrived IMHO. The larger contention is that Homo Sapiens is at or near the peak of our population, and on borrowed time as a species. I will talk more about this later. The many themes here bring together a lot of my recent reading about genetics, anthropology and human development; also the zeitgeisty topics of climate change, global pandemics, and inter-planetary travel.*

I really enjoyed the journey that Gee takes us on from pre-history to possible futures. The former explores how our species rose to prominence, despite the many near Hominin cousins (all gone by inter-breeding and failure to adapt) and one or more existential crises. The rarity of human bands, until relatively recently, has affected the variety in our gene pool and our resilience to disease, as has our dependence on a much more limited range of - selected & enhanced - foodstuffs than our hunter-gatherer ancestors. So we have ‘risen’ (like Rome) and are now at the precipice of the ‘fall’, due to over-population, climate change, and falling fertility & birth rates.** Do we suffer the fate of all(!) species and die off, or do we buy time by modifying our own genome and/or seeking places to live outside our home planet! Fascinating subjects, a perfect mix of science, history and technology for me.

*I will return to my reading history (and bookshelves) another time. It almost feels like I have a plan!

**or rather a slowing in the growth, world population is predicted to peak by c2100 and then fall, possibly drastically.

On Second Thoughts ...

Not particularly one of Gee’s main interests in this book, but he talks about how humans have adapted our environment to live all over the world, under the sea, and in space … and extrapolation of this idea to envisage longer term off-planet communities. Whatever the reasons for our pre-eminence (our brainpower, communication, language, team-work etc.) we have effectively externalised and outsourced our [genetic] adaptability and specialisation with tools and technology, at the expense of a dead-end genome and vulnerable ‘wetware’ bodies. Our voracity for resources and expansion is limitless and unchecked, which is a red flag for any apex predator. No wonder AI and sentient robots are the new existential bogeymen (even more than natural disasters or predators), as they represent a challenger ‘species’ to the tech-enabled and enhanced humans. The red herring of intelligence and self-awareness is irrelevant when it comes to a fight-to-the-death for survival and resources, as bacteria and viruses have always known!

[Carlo Cozzi · Rating 3 out of 5]

I found the book overall quite interesting. It covers a wide range of topics, many genuinely thought-provoking, and offers a decent amount to learn. That said, it suffers from a serious flaw: repetition. The author tends to recycle the same points from chapter to chapter, which means the book could easily be shorter, more direct, and more impactful without losing anything of value.
Despite this, the concept is compelling. It’s a good overview of the different human species and hominids that have existed, and how (and why) they’ve evolved and disappeared over time.
The most striking takeaway for me is the author’s argument that what set Homo sapiens apart wasn’t superior intelligence, but population size. When populations are too small, technology and knowledge can vanish; skills must be reinvented over and over before they finally take root.
But my favorite part came at the very end, where the author briefly invites us to consider humanity’s future in space. Sadly, this section was just an afterthought; I wish far more space had been devoted to it. The idea that humans have been preparing for space life since the very beginning is fascinating. For centuries (in the last one more than before), we’ve been building environments, houses, offices, cities, that insulate us from nature, controlling temperature, light, and air. In a way, we’re already practising for living on another planet.
Yet this thought brings a darker question: what happens to humanity if we completely sever ourselves from nature? Already, city people can be anxious about insects, dirt, or wilderness, feeling uncomfortable or even unsafe in the natural world. If we extend that trajectory, living only in enclosed, artificial spaces, perhaps on a spaceship, what will humans be? What purpose will we serve if our connection to nature, and even our biological roles, are stripped away?
The book touches on one unsettling idea: that pregnancy might not be viable in space, which could lead to artificial gestation outside the human body. This would be an extreme step in the dehumanization of humanity, removing one of our most fundamental natural functions. If robots run the ship and machines provide everything we need, will humans be reduced to doing small, token tasks and distracting themselves with entertainment? In such a future, why even keep humans alive at all?
This leaves me pondering a question: if humanity is completely detached from nature - our origin and our context - what is our role, and what is our purpose?

[Ryan · Rating 3 out of 5]

Not sure why this paperback edition is listed as out next month, but I got a copy of it from the library. The title and premise of this book is clever at attracting one to read its contents, and after finding out that the author is already famous because of his earlier book on the history of life on Earth, I went for it. While there were many interesting subjects discussed, about the rise of hominids and our own species, and a brief history of our path to dominance and the current problems due to our success, from environmental woes to genetic weakness and health issues, the argument for our demise and the purported solution I found quite flawed.

Relying on historical data on the average lifespan of mammalian species, and some statistical inference, Gee puts the inevitable extinction of the human race between 8,000 to 12 million years from now, with a bias to the closer time frame, approximately in the next ten thousand years or so he believes. The biological reasons for this is due to declining fertility and the trend of a shrinking global population sometime from the middle of this century. He then exhorts that we should double our efforts at colonizing space soon, before we disappear from the Earth as our civilization declines.

I beg to differ on this logic. The decline in fertility and population is not a one way street for certain, as we are likely experiencing typical density dependence effects, in the parlance of ecologists, where population growth declines as the density of individuals increases due to various reasons like competition. Should carrying capacity be breached and result in a crash, populations of animals (yes we are animals) do bounce back, eventually, provided our planet can still support human life. In this vein, going to space may not be that necessary after all as an escape valve. Why not focus on curbing our appetites instead and living within the Earth's boundaries, striving for a truly sustainable civilization at a considerably lower population?

In any case, the book is still worth reading for the interesting facts and darkly humorous undertones, just that the call for going to space was too trite and banal for me.

[Drew · Rating 1 out of 5]

I don’t seem to get on well with pop science. I heard the author on David Runciman’s podcast, and intrigued by his hypothesis, bought the book. A few chapters in I was confronted with my usual dislike of the way that a certain kind of scientist tries to write for a wider public: not exactly patronizing, but also not the tone that they would use when addressing their academic peers.
I may not have a doctorate in any of the sciences, but neither do I need to be spoken to as if the only way you can keep my attention is by writing in a lightweight, jokey way. Rather than reinforcing the message or adding substance to the argument, this merely distracts from what Henry G is trying to tell us, namely, that the forces of evolution and natural selection will ultimately lead to the extinction of homo sapien sapiens just as it has done for every other species thrown up by nature.
This isn’t perhaps a particularly new revelation, but the initial argument is interesting in that it puts a finger on the moment that the rot set in, and that’s not where one might suspect. Rather, in the authors telling, it was the moment at which our species came to dominate over and eliminate all other surviving humans, such as the Neanderthals, Denisovans and others.
This genially pessimistic thesis is a great starting point for an “all downhill from here” narrative but Mr Gee squanders his early advantage with his lightweight, bantering tone, weak argumentation and a final speculative leap into space that was remarkable only to the extent that I could barely believe he spent more than an afternoon or two of online research to come up with his conclusion.
I also have to wonder why the demise of humanity should really be seen as a problem that needs to be solved. Given what we’ve been up to in the last 10,000 years I’m really not sure we deserve another 10,000 anyway. Thoughts?

[Imlac · Rating 3 out of 5]

I'm a fan of Henry Gee's popular science books, having enjoyed A (Very) Short History of Life On Earth: 4.6 Billion Years in 12 Chapters and The Accidental Species: Misunderstandings of Human Evolution. He has a knack for clear and very readable explanations, in service of interesting and thought-provoking ideas and theories.

This book is focused on the extinction of the human species. Gee helpfully begins with the long rise, and then traces the sudden fall, of our kind. He provides a thorough catalogue of all the forces working to extinguish us, including climate change and the change in the social role of women (their education and autonomy leading them to reproduce late and a much lower rates than needed to sustain the species). His final part, "Escape", conjectures how we might after all avoid our fate. It is futurism in the respectable sense, backed by solid science and disciplined imagination.

The writing, however, is not as tight, elegant or well-crafted as in the earlier books. Gee tends to repeat the same set of claims, sometimes within a few pages of each other. And he slows and sometimes completely stops the onward flow of his narrative with unnecessarily detailed and technical tangents.

Thanks to Netgalley and the publisher for an ARC.

[Philip Talmage · Rating 4 out of 5]

As Senior Editor, Biological Sciences of the science journal Nature, Henry Gee has to be worth listening to when he speculates about the future of the human race. The book first summarises the antecedence of Home Sapiens, how we came to dominate Earth and how, in recent times, we have been using it up.
But now, the population will cease growing within the next century, then begin to reduce. We may find ways to live in space and so escape confinement to this planet. But we have to achieve this within the next two centuries "before the human population declines to a degree that it can no longer support the technological innovation and creativity necessary to make the move into space".
While any forecast must be uncertain, this last assertion appears to be unsupported by logical argument. Moreover, when it comes to evidence, there are signs that Gee prefers that which will support his thesis. Although widely predicted, there is as yet little evidence that global warming is in fact generating those "extreme weather events", while Gee triumphantly retails the cautionary tale of environmental catastrophe invented by the early European explorers who discovered Rapa Nui (Easter Island) in the North Pacific to explain how "the once-productive environment had been destroyed by the inhabitants" who had been driven to cannibalism by mass starvation - without mentioning that paleontological evidence has failed to support this story.

[Ramesh Nambiar · Rating 2 out of 5]

This is an interesting hypothesis. The Population Bomb alarmed the world over… population growth getting out of hand. This book talks about how the human population may decline and why it is bad.

What I thought… is that this is again a very Caucasian ethnocentric viewpoint. There is an argument that higher the population, greater the innovation… but what’s the limit? US has about 350 million people of which probably 250 million are not educated enough to innovate. The imbalance is more exaggerated in India and China with a combined population of 3000 million! This was not explored- level and investment in education, early childhood development and health… contributing to better outcomes in science and technology advancements. Is there an optimal population for earth? For a country? Is it all about consumption and GDP measures? Why would we as a species not do better on earth with a population of 1 billion? Why would China be worse off in 2050 or 2100 with half the population? Why would India not be better off with a population of 100 or 200 million? India has half the land area as US… why not a proportionally smaller population with higher standards of living?

But most of all… the book is rather repetitive! Like the author and publisher wanted to get to a number of pages! Reminded me of school days when essays were expected to have a certain number of words and we struggled with substance, and resorted to… repetition.

[Andrea Wenger · Rating 4 out of 5]

Human population growth is slowing and will soon reverse, leading to a rapid decline. This provocative book argues that humanity is on a path to extinction. It explores our rise and fall, from scattered groups to a dominant species now facing dwindling resources and escalating threats. The book questions whether we can change course or if extinction is inevitable, offering a vision for a future demanding ingenuity and cooperation.

This book is interesting and informative, but at the same time, I think its premise is a little silly. The fact that human population will begin declining this century is a good thing, not a harbinger of doom. Population will increase by 25% over the current level before it begins dropping. We’re not going to run out of humans anytime soon. And it’s impossible to say what the reproduction rate will be once human population falls to a level that the planet can sustain more easily than it does now. Plus, it seems a bit contradictory to lament falling human population while at the same time raising alarms about declining resources. IMO, this book is much ado about nothing.

Thanks, NetGalley, for the ARC I received. This is my honest and voluntary review.

[Casey · Rating 4 out of 5]

I was happy to receive the audiobook version of this ARC (ALC?), as it was a book I had entered a Goodreads giveaway for, but didn't win.

This was the first book from Henry Gee that I have read, but I appreciated the depth of knowledge he brought to the book. He references his other books (along with various other sources) throughout, which leads me to believe I would enjoy some of his other works as well.

This was less alarmist and political than I anticipated, which I thoroughly appreciated. I listened to this after finishing Nexus from Noah Yuval Harari which was more on the edge of anxiety provoking, where The Decline and Fall of the Human Empire: Why Our Species Is on the Edge of Extinction felt more intriguing. Perhaps it was Gee's writing style, or that this was a more brief exploration of the past catastrophes and the long road to where we are today, but the discussion felt more approachable. Specifically, I enjoyed the topic of other hominids and the interaction/interbreeding with homo sapiens.

Because I was intrigued, I wish there was more to this book. While fantastic for introduction or more casual review of the rise and (potential) fall of our species, I would have appreciated a deeper dive into some of the suggested contributing factors.

Thanks to NetGalley, Henry Gee, and Macmillan Audio for the opportunity to read and review an ARC/ALC.