Earth during the Hadean was like our image of hell

Hadean to Capitalocene

Climate is change. But today climate change represents an immediate danger to human civilisation and can only be mitigated if far-reaching and truly radical measures are taken. Jack Conrad looks back at the deep past and towards an uncertain future

Let us begin at the beginning.

Our planet dates back around 4.6 billion years to the formation of the solar system. During the Hadean eon, Earth’s molten surface slowly cooled and hardened into a solid crust.1 The first atmosphere had abundant amounts of carbon dioxide - perhaps between 10 and 200 times as much compared with today.2 Solar winds stripped away the lighter, volatile gases.

Because of the much closer proximity of Earth’s giant moon compared with today, together with churning volcanic activity and countless asteroid and meteorite strikes, a second atmosphere formed: besides carbon dioxide there was ammonia, methane, carbon monoxide and water. Earth was a hothouse - more like present-day Venus than present-day Mars. Surface temperatures were a sizzling 230°C. Despite that, there were oceans. Heavy atmospheric pressure, maybe up to 90 bar, prevented liquid water evaporating into steam.3

According to the famous theory developed - independently - by Alexander Oparin and JBS Haldane in the 1920s, shallow seas constituted a “primeval soup”.4 The abiotic processing of CHNO compounds resulted in the building blocks of life: ie, prebiotic compounds. Others, more recently, have argued for hydrothermal vents.5 Either way, as shown by the fossil record, simple, heterotrophic life spontaneously began some four billion years ago.

Five hundred million years later, tiny, single-cell blue-green algae were converting carbon dioxide into oxygen through photosynthesis. Eventually there was enough oxygen in the atmosphere to react with the methane and turn the sky blue.6 So Earth’s third atmosphere is the product of co-evolution. Indeed our climate results from the interaction of atmosphere, hydrosphere, lithosphere … and biosphere.

The ozone layer formed 600 million years ago … and as a by-product provided vital shielding from the sun’s biologically harmful ultraviolet rays.7 However, the evolutionary leap in complex life forms happened in the balmy seas of some 540 million years ago. The Cambrian explosion occupies a mere few million years - in geological terms a blink of the eye - and led to “virtually all major groups of modern animals”.8

Temperatures in the deep past were mostly much higher than today. The Cambrian (600-500 million years ago) 14°C hotter. The Silurian (425-405 million years ago) 4°C hotter. The Devonian (405-345 million years ago) 10°C hotter. The Permian (298-252 million years ago) 3°C colder. The Triassic (252-201 million years ago) 10°C hotter. The Jurassic (201-145 million years ago) 8°C hotter. The Cretaceous (145-66 million years ago) 4°C hotter. The Palaeocene (66-55 million years ago) 10°C hotter. The Eocene (55-33 million years ago) 4.5°C to 12°C hotter (all figures being my rough and ready estimate).9

Doubtless, some of these temperature changes were due to planetary wobbles (Milankovitch cycles), volcanic activity and variations in solar brightness. But there is also plate tectonics. Three billion years ago the vast mass of the earth’s surface seems to have been covered with water. There were only a few spots of dry land. Arctica, or Arctida, was perhaps the first supercontinent, and arose some 2.5 billion years ago (there might well have been others, but, if so, we have mere geological fragments remaining). Eventually Arctica broke apart, but after many more millions of years there were other superseding continents and supercontinents: Kenorland, Columbia, Rodinia, Pannonia.

Beginning in the Neoproterzoic, about 550 million years ago, most of Earth’s land masses are found joined together in the Gondwana supercontinent. Meanwhile, in the seas, giant plankton blooms resulted in oxygen increasing to about 20% of the atmosphere (roughly the same as today) - conditions ripe for terrestrial flora and fauna. Probably the migration from the seas began some 500 million years ago.10 Complex life drifted, crept, coiled, clambered and slithered onto the land and rapidly evolved.

Something like our present configuration of continents appeared 60 million years ago. Doubtless this helped establish our contemporary algific climate regime. The North American and Eurasian land masses more or less encircle the northern pole; that and the Antarctic continental plate centred on the southern pole provide almost perfect conditions for ensuring an oscillation between cool and cold conditions. The bulk of Earth’s fresh water is kept frozen in two gigantic ice sheets - which means much reduced sea levels.

Over the last million years there has been a glacial-interglacial, 100,000-year pattern. Each cycle has its own particular features and oddities. Understandably, though, as with any study of the past, data becomes ever more uncertain with increasing distances of time. So the best records we possess go from the interglacial, known as the Eemian, down to the present Holocene period - deep ice cores drilled from Greenland and Antarctica have yielded enormous amounts of information.

In terms of climatic transition the most reliable information is for what is called the Younger Dryas to Holocene, which ended the last ice age. At its maximum, some 15,000 to 20,000 years ago, the Arctic ice sheet extended all the way down to Chicago, New York, Moscow and London and saw much lower sea levels than today. What is now Britain was joined to France, the Netherlands and Denmark. Recent studies give a -6.1°C average temperature.11

The transition to our present-day climate regime occurred some 11,650 years ago and saw the retreat of the great ice sheets. The tipping point seems to have been only a decade or two long. It is argued that the “speed of this change is probably representative of similar, but less well-studied, climate transitions during the last few hundred thousand years”.12

During the present (Holocene) interglacial period, there have been cold and dry phases occurring over a roughly 1,500-year cycle, and climate transitions on a decade-to-century timescale. There have been little ice ages, as well as bursts of relative warmth. Between 1100 and 1300, for example, Europe experienced temperatures which were 0.7°C to 1.6°C higher than today (though, it must be emphasised, this was a local, not a global, phenomenon, elsewhere things were cooler). That allowed for more productive agriculture throughout the continent and saw flourishing English vineyards.

It is also worth recalling, though, that the Thames regularly froze solid during mid-17th century winters and that the years from 1805 to 1820 were comparably cold and bleak. What we are experiencing at present certainly needs to be put into the context of the transition from the little ice age, which finally ended around 1880. Temperatures would be expected to rise … marginally. But, of course, what we have seen is way beyond that: temperatures increased on average by 0.08°C every decade since 1880 and by an average 0.18°C since 1981.13 The main cause is human-induced greenhouse gasses: eg, in the 20th and 21st centuries “the level of carbon dioxide rose by 40%” - now the highest for some 20 million years (Met Office).14

Wrong politics

Our potted history of global atmosphere, temperature variation and continental drift helps explain why those with even a passing knowledge of the earth sciences consider the Campaign against Climate Change such a weird choice of name. Cynically well intentioned, CCC is politically safe and soggy. SWP popular frontism oozes from every pore. Capitalism, socialism, the working class all go unmentioned. And, of course, no less to the point, ‘climate’ and ‘change’ go together like ‘weather’ and ‘change’. The two are inseparable. The weather changes from hour to hour, day to day and month to month. Imagine a Campaign against Weather Change. It would be too, too silly.

According to its ‘mission statement’, CCC exists to “influence those with the greatest power” to “minimise” the “harmful effects of climate change” with the “utmost speed and resolution”. Flattering courtiers similarly pleaded to Canute, the 11th century king of Norway, Denmark and England, to reverse the incoming tide. Needless to say, as he famously demonstrated (purportedly on Thorney Island), no-one, not even he, could pull off such a feat. Nor, despite CCC “street demonstrations” and avoidance of “detailed questions” in the attempt to “bring together as many people as possible”, can we really expect “those with the greatest power” to agree an “international climate treaty” that will “minimise” the “harmful effects of climate change”.15 The “international climate treaty” has long been agreed (Paris Cop21 - adopted December 12 2015, signed April 22 2016, effective November 4 2016). But will it “minimise” the “harmful effects of climate change”? Seems unlikely on present evidence.

Surely to “minimise” those effects our sights must be set far higher than “street demonstrations” (or glue-down road protests). We must talk about capitalism. We must talk about socialism. We must talk about organising the working class into a ruling class. The CCC ‘mission statement’ needs more than a long overdue update. No, a different kind of politics is needed.

Climate is big weather. Karen Bice gives the following definition: climate “equals weather ‘averaged’ over a time period of more than one year or more”.16 In other words, there is nothing fixed about the climate. Climate change has never ceased, is ongoing and must therefore be considered inevitable. Notions of a stable, an unchanging climate are, to put it mildly, badly misconceived.

While the climate constantly undergoes change, that happens within a self-adjusting system: that is, within a relatively stable equilibrium, and hence distinct geological epochs and periods. However, yes, there are tipping points - mostly involving transitions lasting no time at all in geological terms (often corresponding with mass extinctions of flora and fauna).

True, till recently, most scientists thought that all large-scale climate change took place over a timescale of many millions of years: ie, at rates unnoticeable during a human lifetime. Not least for political reasons, gradualism was the ruling orthodoxy. But no longer. Eg, “All the evidence indicates that most long-term climate change occurs in sudden jumps rather than incremental changes.”17 In point of fact, through mathematical advances, supercomputers and new modelling techniques that link together weather and climate, scientists can now make extraordinarily accurate predictions, including when quantitative change tips over into qualitative change. That is what got Syukuro Manabe, Klaus Hasselmann and Giorgio Parisi their Nobel prize in physics.

Such conclusions were anticipated by GWF Hegel and his objective idealism. Marx and Engels, of course, turned Hegel upside-down (put him onto his feet). What Hegel developed as mysterious laws of thought all leading to the ‘absolute idea’ (though often illustrated with striking examples drawn from nature and history) could be put onto solidly materialist foundations and presented in a straightforward manner. According to Engels, writing in Dialectics of nature (1873-86), there are three general - dialectical - laws of nature and human society: (1) the transformation of quantity into quality; (2) the interpenetration of opposites; (3) the negation of the negation.18 Long before Marx and Engels (and Hegel), it should not be forgotten that the best of the ancient Greek philosophers saw the world in ceaseless flux, coming into being out of a fiery chaos, and how things change into their opposites. Similar, wonderfully impressive, dialectical insights can be found amongst Chinese and Indian sages too.

However, in particular during the 19th and 20th centuries, the bourgeois establishment lived in dread of sudden change. The French revolution of 1789, the 1793-94 Reign of Terror, Chartism, the 1848 revolutions, the 1871 Paris Commune, the rise and rise of mass Marxist parties and the world-shaking October Revolution saw to that. Sudden change - well, until the promotion of ‘colour revolutions’ - was equated with artificiality, aberrance, threat and catastrophe. Therefore, (Tory) fixity, or its opposite, (Whig) gradualism, were the ruling ideas, and not only in politics.

Isaac Newton allowed for the movement of the planets, but on orbits given fixity by “universal gravitation”19 - all given first impulse by the finger of god himself. The steady state theory of the universe was only finally overthrown in the mid-20th century. Edwin Hubble’s observations and the calculations made by Albert Einstein showed that the universe was expanding and inherently unstable. Fred Hoyle represented the conservatives’ last stand. The coup de grâce came with the work of Martin Ryle on quasars and the accidental discovery of the cosmic microwave background by Arno Penzias and Robert Wilson. The big bang about 13.8 billion years ago and the ‘inflationary universe’ are nowadays accepted as scientific fact.

Similarly with biology. Lorenz Oken, Jean-Baptiste Lamarck, Karl Ernst von Baer and above all Charles Darwin overthrew old Linnaen notions of the fixity of species. Instead they agued for evolution. One species led to another. Studies of the fossil record, studies of domesticated plants and animals, studies of variations in the wild - all proved it. Famously though, Darwin endlessly delayed publication of his On the origin of species (1859). He feared outraging Christian sensibilities. He also feared Chartist revolution.20 And precisely because of its revolutionary implications, Darwin’s theory of evolution through natural selection was determinedly gradualistic in presentation.

Most modern readers fail to even notice how much of the Origin consists of a defence of gradualism rather than an exposition of natural selection. In the concluding chapter Darwin declared his commitment to the postulate: “Natura non facit saltum” (nature does not proceed by leaps).21 It was Stephen Jay Gould and Niles Eldredge who finally broke through this orthodoxy. In 1972 they presented their theory of punctuated equilibrium. Species undergo genetic drift, but are essentially stable as phenotypes, crucially the emergence of a new species - speciation - occurs via “sudden” transitions.22 The debt to Marxism is all too apparent.

Many other such examples in science could be cited, but that would be tiresome. The tipping point, jump, sudden shift, phase transition - call it what you will. The dialectical leap is generally accepted in fact, if not in name.

Upsides, downsides

Climatic change can doubtless produce new opportunities. Palaeontologists note that growing polar ice sheets and the spread of the African savannah 3.6 to 4 million years ago coincided with the “split” in the “evolutionary line” between ourselves and chimpanzees and gorillas.23 Our ancestors came down from the trees and began to walk upright.

Subsequently, other glacial periods and lower sea levels eased migration into Australia and then the Americas by fully modern humans. Getting to Australia from Asia some 60,000 years ago needed only a short hop from the (much larger) island of Timor. With Siberia connected to Alaska by the Bering land bridge, tribal groups - perhaps just five of them - simply wandered into America 22,000 years ago and 10,000 later had peopled the whole of the Americas all the way down to Tierra del Fuego.24 The beginning of crop agriculture in the Middle East certainly corresponds very closely with a sudden warming event, which marks the onset of the Holocene. Desertification slowly squeezed people into remaining riverine strips of greenery. A mixed blessing. For the emerging elite there came power, palaces, luxury goods and leisure; for the masses a nutritionally much reduced diet and backbreaking toil.25

However, there are unmitigated societal downsides. Archaeologists blame climate change for numerous civilisational collapses: eg, the great Bronze Age states of the eastern Mediterranean, the Harappan in the Indus valley and the Khmer in southeast Asia. The Mayan cities of central America were abandoned one by one and “most cultural activities ceased”.26 True, there is the danger of monoexplanation. Invasion by neighbouring tribes or states, civil war, disease in crops and humans and the class struggle all play their part too.

Either way, we certainly face another definite downside, when it comes to climate change today. The danger, though, is not the collapse of civilisation on a local or even a regional scale, but globally.

The key findings of the Intergovernmental Panel on Climate Change in its sixth report are alarming, widely known and well worth repeating: human-induced greenhouse gas emissions are “unequivocally” the cause of rapid changes to the climate and, unless dramatic and sustained action is taken, the 1.5°C limit will be exceeded in the early 2030s.27 The aim to limit global warming to “well below” 2°C - “preferably” to 1.5°C - compared to pre-industrial levels was, of course, agreed by the Paris 2015 Cop21 meeting and is signed up to by 195 parties.28

Now, says the IPCC, it is “code red”. Human activity is changing the climate in ways “unprecedented” in thousands - or hundreds of thousands - of years. Some of the changes are likely to be “irreversible” over centuries or millennia - including the melting of polar ice, sea level rises and the acidification of the oceans.29

Predictions about total warming are, of course, dominated by past and future carbon emissions, but, says the IPCC report, cuts must also be made to the shorter-lived methane emissions - responsible for roughly 30% of post-industrial global warming and 80 times more potent, when it comes to climate change.

In terms of human activity, methane is released primarily through biomass/biofuel burning, gas/oil production, rotting waste in landfill sites and, of course, meat and dairy farming. Cutting methane emissions by 30% over the next decade is, reportedly, a US-EU-UK “priority” for November’s Cop26 in Glasgow.30

But, whatever happens with methane, we seem well on course not only to hit the 1.5°C limit a lot sooner than first predicted, but there is the danger of reaching 2°C and going beyond. The IPCC warns that we are at or very near the “tipping point”.31 When quantity turns into quality, a “multiplier effect” kicks in and through feedbacks and couplings we get an entirely different climate system.32 Leave aside ocean currents, such as the Gulf Stream, slowing down or switching off entirely;33 mid-latitude land masses are at risk of being hit with searing, almost impossibly high, temperatures. Meanwhile, polar regions get far less cold during the winter months and in the summer release billions of tonnes of extra melt-water into the seas and oceans.34

Keeping to the Paris 1.5°C limit and preventing runaway climate change requires immediate, decisive and large-scale reductions in greenhouse gas emissions - of which there is no sign to date. On the contrary, emissions continue to rise. The explanation for this is all too obvious. Eg, governments of all stripes leave urban sprawl, road building and the whole car economy going unquestioned. The much vaunted transition to electric vehicles is more a giant selling opportunity than any kind of a genuine solution. Not only does electricity still have to be generated - much still relying on coal, oil and gas power stations - but there is the steel, plastics, glass, computer chips, batteries, tyres, etc that go towards making an electric vehicle. So, even if there is a 100% transition to renewable power sources, there remains the large-scale release of greenhouse gases. The same applies to other major sources of human-induced greenhouse gas emissions: housing, airflight, shipping, agriculture and industry. It is business as usual ... and, needless to say, business is driven by the capitalist M-P-M' imperative.

If emissions are not significantly reduced in the next decade, then reaching 3°C is all too conceivable - an apocalyptic scenario: although it will take thousands of years, the polar ice caps melt, sea levels head for a 10-metre rise, there is a further thaw of permafrost and another feedback surge in global temperatures. There is unavoidably, as a consequence, the mass extinction of flora and fauna. Countless cities are inundated: Alexandria, Dhaka, Jakarta, Bangkok, Kolkata, Miami, Houston, New Orleans, Rotterdam, Rio de Janeiro, Osaka and Shanghai lie top of the list. Along with much of Europe and western Asia, Britain eventually fragments into a series of islands. Oxford finds itself one of many new coastal towns. The North American wheat belt turns to desert. We effectively return to the conditions of the early Eocene 55-49 million years ago.

As an upside, true, despite the long, sunless winters, the far north of America and Asia becomes habitable by ‘normal’ people, along with Antarctica. But what this presages is not exciting new opportunities for humanity: rather a new dark age. Indeed there is the distinct possibility that large parts of the planet become uninhabitable, as temperatures rise above our “physiological limits”.35 Tim Palmer, professor of climate physics at Oxford University, warns that if we do not halt our greenhouse emissions soon, we face “some kind of hell on Earth”.36

As the IPCC emphasises, even if the capitalist ruling class somehow manages to get its act together by drastically reducing emissions, the climate will not return to the patterns we have been used to in the recent past. A 1.5°C warmer world will see an increase in “unprecedented” weather events. Disastrous floods, droughts, heatwaves and fires will become far more frequent and far more intense.


With its imperialist hierarchy, ruthless exploitation of nature and never satiated lust for profit, capitalism is the major driver of global warming - despite its different political economy, the Soviet Union and its ‘socialist’ bloc made no difference here. As for China - today the world’s biggest emitter of greenhouse gases - it is, of course, fully integrated into the global capitalist economy. Some talk of the Anthropocene, as if it is an undifferentiated humanity that is to blame. But it is surely better, more accurate, to talk of the Capitalocene.

For many on the left, not unreasonably, capitalism is defined as categorically “incapable of carrying out the radical measures required” (Socialist Appeal).37 “Capitalism can’t solve the climate crisis” (Socialist Worker).38 “Can this climate emergency be halted under the current world economic, political and social system - capitalism? .… No” (The Socialist).39 However, not even the most fabulously wealthy billionaires or the system’s top politicians and state actors are so blind that they cannot see that something must be urgently done. True, it is hard to imagine governments such as Boris Johnson’s Tories ever carrying out a programme that would actually achieve net zero emissions - after all, that would require a dramatic restructuring of power generation, industry, agriculture, transport, housing provision, etc. Therefore, in all probability, the corrupt, grasping, self-interested Tories will confine themselves to little more than gestures, cheap platform rhetoric and legislating for an electorally safe distant future. Meantime they carry on as usual: more nuclear power, more roads, more air travel, more poor-quality housing … crucially, more of everything - ie, more economic growth.

Yet, as seen with the Covid pandemic - and World War II and World War I before that - the ruling class was prepared to allow governments to temporarily suspend the law of value. The normal workings of capitalism were overridden, curtailed or tightly directed in order to achieve agreed state aims.

The more intelligent sections of the left have written about how the Tories, and other governments too, introduced ‘Covid socialism’ - roughly equivalent to the ‘war socialism’ put into effect by the German high command in 1916: ie, the use of concentrated state power to deal with a dire emergency. The Oxford AstraZeneca vaccine is a good example. Developed double quick, produced on a non-profit basis, it was then rolled out and administered according to need by the NHS.

In terms of the general interest - more particularly the general capitalist interest - governments will take what are usually regarded as extreme measures. Tory chancellor Rishi Sunak talked about tearing up his economic textbooks, doing what is necessary, thinking the unthinkable and so on. Though fraught with horrendous difficulties, not least because capitalism - from the level of the firm to that of the state - is characterised by internally generated contradictions, we should not categorically discount the possibility that this will happen with the climate crisis. After all, the capitalist class lives on the same fragile planet as the rest of us (even if Elon Musk would like to rocket off to a frigid, lifeless, almost airless Mars).

So climate socialism imposed by a firefighter capitalist state - maybe urged on by Friends of the Earth, the Green Party, XR and CCC demands for the declaration of a ‘climate emergency’, maybe with ‘beyond politics’ green advisors, enlightened technocrats and the armed forces playing a leading role - such a state could conceivably impose draconian restrictions on greenhouse gas emissions by reorganising industry, transport, housing and agriculture.

Of course, that, or something like it, would have to happen in all the major countries if the rise in global warming is to be limited to “well below” 2°C, or even to 1.5°C. Adding to that little difficulty, the global hegemon, the United States, is in visible decline. So there is no effective power that can enforce the general, capitalist interest. Indeed, in the attempt to reverse its decline, all the signs are that Joe Biden will hypocritically use China’s increasing greenhouse emissions to further demonise it in the eyes of ‘world opinion’ and block its rise through yet further sanctions and trade barriers. Combating global warming thereby becomes a weapon in big-power rivalry. War is the logical outcome.

Even on a purely national level, we should have no illusions about any eco- or climate socialism, introduced, overseen and enforced by the capitalist state (or for that matter the Xi Jinping regime). As with war socialism, there will be monumental blunders, severe restrictions on democratic rights, attempts to drive down popular living standards - all accompanied by endemic corruption and corresponding opportunities for well connected insiders to enrich themselves beyond the dreams of Croesus.

Nor will such a climate socialism evolve peacefully and smoothly into proletarian socialism. True, we reach a partial negation of capitalist production - the outer limits of capitalist society. But, because there is a swollen, parasitic, aggressively repressive bureaucratic state, what we have is the extreme opposite of proletarian socialism. Nonetheless, there is a relationship between climate socialism - in reality capitalism attempting to save itself on the back of the working class - and proletarian socialism.

After all, in the paragraph above, substitute for the firefighter capitalist state the working class organised as the state power. Such a state based on extreme democracy, closely coordinating with other similar states across the globe, that radically reorganises power generation, industry, agriculture, transport and housing; a state that reduces greenhouse gas emissions to net zero and then below; a state that subordinates production to need. Then it is clear that such a state is nothing more than capitalist climate socialism that really does benefit the whole of humanity - and therefore represents the negation of capitalism and the first step towards a classless, moneyless, stateless and ecologically sustainable communism.

  1. en.wikipedia.org/wiki/Hadean.↩︎

  2. sciencing.com/earths-first-atmosphere-contained-gases-2034.html.↩︎

  3. Atmospheric pressure is measured according to a bar unit. At sea level the average atmospheric pressure on Earth today is roughly 1.013 bar and on Venus around 90 bar. See pubsapp.acs.org/subscribe/archive/ci/30/i12/html/12learn.html.↩︎

  4. See en.wikipedia.org/wiki/Primordial_soup#Heterotrophic_theory; AI Oparin The origin of life Mineola NY 2003; S Tirard, ‘JBS Haldane and the origin of life’ Journal of Genetics November 2017.↩︎

  5. See www.nature.com/articles/nrmicro1991.↩︎

  6. forces.si.edu/atmosphere/02_02_03.html.↩︎

  7. See www.albany.edu/faculty/rgk/atm101/ozone.htm.↩︎

  8. SJ Gould Wonderful life: the Burgess shale and the nature of history London 1990, p24.↩︎

  9. en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg.↩︎

  10. www.nhm.ac.uk/discover/news/2018/february/plant-life-on-earth-is-much-older-than-we-thought.html.↩︎

  11. www.nature.com/articles/s41586-020-2617-x.↩︎

  12. J Adams, M Maslim and E Thomas, ‘Sudden climate transition during the Quaternary’ Progress in Physical Geography March 1999: www.esd.ornl.gov/projects/qen/transit.html.↩︎

  13. www.climate.gov/news-features/understanding-climate/climate-change-global-temperature.↩︎

  14. www.metoffice.gov.uk/weather/climate-change/causes-of-climate-change.↩︎

  15. www.campaigncc.org/aboutus/missionstatement.↩︎

  16. www.beloit.edu/~SEPM/Earth_Works/Plate_Movements.html.↩︎

  17. www.esd.ornl.gov/projects/qen/transit.html.↩︎

  18. See K Marx and F Engels CW Vol 25, London 1987, p356.↩︎

  19. I Newton The mathematical principles New York 1846, p385.↩︎

  20. J Bellamy Foster Marx’s ecology: materialism and nature New York 2000, p30, 179.↩︎

  21. C Darwin The origin of the species Harmondsworth 1972, p435.↩︎

  22. For a looking back - N Eldredge and SJ Gould, ‘Punctuated equilibria: the tempo and mode of evolution reconsidered’ Paleobiology Vol 3, No2, spring 1977, p148. For the original essay - N Eldredge and SJ Gould, ‘Punctuated equilibria: an alternative to phyletic gradualism’ in JTM Schopf (ed) Models in paleobiology San Francisco 1972, pp82-115.↩︎

  23. J Gribbin and J Cherfas The first chimpanzee: in search of human origins London 2011, p217.↩︎

  24. See S Oppenheimer Out of Eden London 2003.↩︎

  25. See S Mithen After the ice: a global human history 20,000-5000 BC London 2003.↩︎

  26. www.ncdc.noaa.gov/abrupt-climate-change/Drought%20and%20the%20Ancient%20Maya%2°Civilization. See also RB Gill The great Maya droughts: water, life and death Albuquerque NM 2000.↩︎

  27. IPCC Climate change 2021: the physical science basis p5.↩︎

  28. unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement.↩︎

  29. IPCC Climate change 2021: the physical science basis p28.↩︎

  30. Financial Times September 15 2021.↩︎

  31. IPCC Climate change 2021: the physical science basis p28.↩︎

  32. CW Arnscheidt and DH Rothman, ‘Asymmetry of extreme Cenozoic climate-carbon cycle events’ Science Advances August 11 2021.↩︎

  33. theguardian.com/environment/2021/aug/05/climate-crisis-scientists-spot-warning-signs-of-gulf-stream-collapse.↩︎

  34. climate.nasa.gov/news/2865/a-degree-of-concern-why-global-temperatures-matter.↩︎

  35. www.technologyreview.com/2021/07/10/1028172/climate-change-human-body-extreme-heat-survival.↩︎

  36. ox.ac.uk/news/2021-08-09-oxford-climate-scientists-no-doubt-about-climate-change.↩︎

  37. Socialist Appeal September 2019.↩︎

  38. Socialist Worker September March 26 2019.↩︎

  39. The Socialist September 15 2021.↩︎