The Roman Philosopher Lucius Anneaus Seneca (4 BCE-65 CE) was perhaps the first to note the universal trend that growth is slow but ruin is rapid. I call this tendency the "Seneca Effect."

Friday, April 29, 2022

The Shanghai Lockdown: a Memetic Analysis


Despite evidence that the rise in the number of cases is stalling, the Chinese lockdown in Shanghai and other cities continues, with hundreds of millions of people forced into their homes or in quarantine centers. What's happening? I argue that the Chinese government may have acted -- and still be acting -- on the basis of a meme that has its origin in a military perception of the pandemic.  


A "meme" is a small unit of information that can easily move from one human mind to another. It is the virtual equivalent of a virus in the sense that it "infects" people and influences their behavior. To explain the concept, maybe the best way is with an example: how my grandmother was absolutely convinced that nobody ever should drink a glass of milk without having boiled it first. She was infected with a meme that we could describe as "boil the damn milk." It was simple and direct, but, unfortunately, completely useless in the 1960s, when pasteurization had become common. 

My grandmother was not stupid: she was simply applying a tested method to deal with things she knew little about. The problem is that memes can be (or become) wrong or harmful, and yet they are very difficult to dislodge. In the photo, you see Colin Powell, in 2003, showing a vial of baby powder while claiming that Iraq had weapons of mass destruction. Hundreds of thousands of people were killed largely on the basis of a meme that turned out to be completely false. 

The Covid pandemic is another case of a complex story that most people are unprepared to understand. We should be trained in microbiology, medicine, epidemiology, and more -- no way! So, we rely on simplified snippets to guide our everyday activities. "Wear the damn mask," "stay home," "don't kill granny," "flatten the curve," and the like. That includes our leaders, and even many of the so-called "experts".

But how can we tell whether a meme is good or bad? One way to decide is to look at its origin. All memes have a story. Sometimes they begin as sensible precautions ("boil the milk before drinking it") but, in some cases ("lock everybody inside their homes"), they have a more complicated story. Where does the lockdown meme come from? Its origin can be found in the evolution of the concept of "biological warfare." But let's go in order. 


The Militarization of Biotechnologies

Biological weapons have been around for a long time in history. Ancient writers tell us of cadavers of infected people shot into besieged cities using catapults. It must have been spectacular, but it doesn't seem to have been common or especially effective. The problem with biological weapons is similar to that with chemical weapons. They are difficult to direct against specific targets and always carry the risk of backfiring. So, in modern times, bioweapons were never used on a large scale and, in 1972, a convention was enacted that outlawed biological warfare. That seemed to be the end of the story. But things were to change.  

You see in  Google Ngrams how the interest in biological weapons started to grow from the 1980s, onward.

    

The Ngrams results are confirmed by an examination of the scientific literature, as you may see by using Google Scholar or the Web of Science. The figure shows the number of papers dedicated to biological weapons (note that in the figure years go right to left in the graph and that the 2022 data are still incomplete.)

The origin of this renewed interest lies in the development of modern genetic manipulation technologies, supposed to be able to create new, and more deadly germs. But they can do much more than that: what if you could "tailor" a virus to the genetic code of specific ethnic groups, or even to the DNA of single persons? That remains (fortunately) for now in the realm of science fiction, but there is a simpler and more realistic approach. You can direct a virus to harm the enemy while sparing your population. You can do that if you have a vaccine, and they don't (like the old Maxim gun in colonial warfare). Considering that biological weapons are also cheap, you can see how the idea of biological warfare has become popular, with China often believed to be a leader in this field. You can read an in-depth discussion on this point on Chuck Pezeshky's site.

Before going on, stop for a moment to remember that these are just ideas: they have never been put into practice. And you are discussing lethal viruses that can kill millions (maybe hundreds of millions) of people. What could go wrong? Nevertheless, the idea of a weapon that only kills your enemies while sparing your forces is an irresistible meme for military-oriented minds. Then, once the meme is loose in the memesphere, it starts acting with a force of its own. The increasing interest in bioweapons indicates that during the past 3-4 decades, military planners started believing that "genetic warfare" was a real possibility. At this point, strategic planning for a biological war became a necessity, in particular about what should have been done to prepare a country to react when targeted with bioweapons.

The diffusion of this meme generated a revolution in the views on how to contain an epidemic. Earlier on, the generally accepted view favored a soft approach: letting the virus run in the population with the objective of reaching the natural "herd immunity". For instance, in a 2007 paper, the authors examined a possible new influence pandemic and rejected such ideas as confinement, travel bans, distancing, and others. On quarantines, they stated that "There are no historical observations or scientific studies that support the confinement by quarantine of groups of possibly infected people for extended periods in order to slow the spread of influenza." 

But when the military meme of biological warfare started emerging, things changed. A bioweapon attack is nothing like a seasonal flu: it is supposed to be extremely deadly, able to cripple the functioning of an entire state. Facing such a threat, waiting for herd immunity is not enough: the virus has to be stopped fast to allow the defenders to identify the virus and develop a vaccine. 

You can find several documents on the Web advocating an aggressive attitude toward epidemics. One was prepared by the Department of Homeland Security in 2006. Another comes from the Rockefeller Foundation in 2010, where you can read of a scenario called "Operation Lockstep" that described something very similar to what came to pass in 2020 in terms of restrictions. Possibly, the most interesting document in this series is the one written in 2007 for the CDC  by Rajeev Venkayya. The document didn't use the term "lockdown" but it proposed a drastic series of measures to counter a possible outbreak that leading nearly two million victims in the United States only. It proposed a series of restrictions on the movement of people and, for the first time, the concept of "flattening the curve." It had a remarkable influence on the events that took place in 2020. We'll go back to this graph later. 


Up to 2020, all these ideas remained purely theoretical, just memes that floated in the memesphere. Things were soon to change. 


The Wuhan Lockdown meme

In early 2020, the Chinese government reported the discovery of a new virus, that they labeled SARS-Cov-2, rapidly spreading in the city of Wuhan. The authorities reacted by enacting a strict lockdown of the city and a partial one in the province of Hubei. The lockdown lasted from Jan 23 to April 8, a total of about 2 months and a half. 

It was an extraordinary event that finds no equivalent in modern or ancient times. Of course, quarantines have been known for centuries, but the idea of a quarantine is to confine people who are infected or who have been in contact with infected people. A lockdown, instead, means locking down everybody in a large geographical region. It had been tried only once in modern history, when a three-day lockdown was implemented in Sierra Leone with the idea of containing an outbreak of Ebola. It had no measurable effect on the epidemic. 

Many people proposed elaborate hypotheses about how the Chinese government may have been planning the pandemic in advance for strategic or political reasons. I don't see this idea as believable. Citing W.J. Astore, "People who reach the highest levels of government do so by being risk-averse. Their goal is never to screw-up in a major way. This mentality breeds cautiousness, mediocrity, and buck-passing." I think the Chinese government is not different. Governments tend to react, rather than act. They also tend to be authoritarian, and a drastic lockdown is surely something that they favor since it enhances their power. 

Seen in this context, it doesn't matter if the SARS-Cov-2 virus was a natural mutation of an existing virus or, as some said, it had escaped from the biological research laboratory in Wuhan. What's important is that the Chinese authorities reacted "by the book." That is, they put into practice the recommendations that could be found, for instance, in Venkayya's CDC paper, although, of course, that doesn't mean that they actually read it. The Chinese surely had their own recommendations on preparedness that we may imagine were similar to those fashionable in the West. They may have believed that the virus was a serious threat, and they may even have suspected that it was a real biological attack. In any case, it was an occasion for the Chinese leaders to show their muscles and, perhaps, also to test their preparedness plans.

Here are the results of the first phase of the pandemic in China. We see how the number of cases moved along a typical epidemic curve that started in January 2020 and went to nearly zero after two months, and there remained for two years.

  

There is no doubt that the Chinese government saw this result as a success. Actually, as a huge success. Don't forget that the initial reports had described an extremely deadly virus, of the kind that could cause tens of millions of victims. In practice, the deaths attributed to the SARS-Cov-2 virus in China were about 5000. Over a population of a billion and a half, it is an infinitesimal number, and the probability for a Chinese citizen to die of (or with) Covid during 2020 was of the order of 2-3 in a million. Infinitesimal, indeed. But was it was a success of the containment policies? Or simply the result of the virus being much less deadly than it had been feared to be? Whatever the case, whoever took the decision of enacting the lockdown also took the merit for its perceived success. It was a personal triumph for China's president, Xi Jinping. 

The apparent success of the Wuhan lockdown generated a new, powerful meme about the effectiveness of the drastic NPI measures based on lockdowns, distancing, cleaning, disinfecting, masking, etcetera. They seemed effective not just in terms of "flattening the curve", but also as methods to control the epidemic and arrive at a condition of "zero covid." Memes such as "stay home" spread to the Western governments, just as the SARS-Cov2 virus spread to Western countries. The memes of "flattening the curve" and of "zero covid" were remarkably successful, as you can see in these data from Google Trends: 


Initially, it seemed that the Covid epidemic in Europe would disappear after the first wave, thanks to the NPIs. European leaders may have been genuinely convinced of this. For instance, in November 2020, the Italian Minister of Health, Mr. Roberto Speranza, published a book titled "Why we will be healed" taking credit for the successful eradication of the epidemic in Italy. But shortly afterward the number of Covid cases in Italy restarted to grow, and Mr. Speranza hastily retired his book from bookstores and from the Web. It was as if that book had never existed. In no country in the West, the number of cases could be lowered to zero, nor the epidemic could be limited to a single cycle as it had been done in China. The comparison of two years of data for China and the US is simply dramatic:



Many Chinese people seemed to take this result as a demonstration that the Chinese society is superior to the Western one because of the better discipline and self-control shown by Chinese citizens. It is an opinion (another meme) that could be maintained as long as the epidemic was at a truly zero level in China. 

Maybe, but a little more than two years later, things changed in China. The virus started spreading in the Southern areas of the country despite a new, drastic lockdown enacted by the authorities. Here are the most recent data available.

   


And you see that China went along the same path that several Western countries followed. After a lull in the spread of the virus, they concluded that the virus was eradicated. But then a new, stronger wave arrived. China didn't do so much better than the West, after all. 


The Memes that won

Up to March 2022, the China lockdown policy was seen as an exemplary case of successful containment of an epidemic. But the Shanghai lockdown changed everything. I argue that what we are seeing is a meme that got loose in the mind of politicians and led them to make several bad mistakes. 

The point, here, is to define success and failure in the containment of a pandemic. But what metric would you use? Let's go back to Venkayya's diagram in the 2007 CDC report, reproducing it here again. 



Do you notice what scam this diagram is? This figure is not based on data, has no experimental verification, no references in past studies. It is just something that the author, Mr. Venkayya, thought was a good idea. The problem is that the diagram cannot be quantified: it shows two nice and smooth theoretical curves. But, in the real world, you would never be able to observe both curves. Think of the epidemic in Wuhan: which of the two curves describes the real-world data? You cannot say: you would have needed two Wuhans, one where the restrictions were implemented, another where they weren't. Then, you could compare. 

Of course, in the real world, there are no two Wuhans, but there are 51 US states that applied different versions of the concept of "restrictions" during the pandemic. A recent study by the National Bureau of Economics Research went to examine how the different states performed and found essentially no effect of the restriction on the health of the citizens. There are other studies based that show how the effect of NPIs such as lockdowns, distancing, masks, etc., is weak, if existing at all. 

That leaves open the question of why the first lockdown in Wuhan was perceived to be so effective that it was replicated all over the world. The key, here, is the term "effective." If the virus had been as deadly as it was believed to be, maybe even a biological weapon, then, yes, you could claim that the Wuhan NPI had contained it. But later experience showed that the Covid virus was not much more lethal than that of normal influenza. Some data show that it may have been endemic before the outburst of 2020, so the immune system of the Chinese may have been already equipped to cope with it. That would also explain why the 2022 wave was so much stronger: the Chinese had not exposed their immune system to viruses for nearly two years, and they had become especially vulnerable to new variants.  

At this point, I can propose an interpretation for the reasons for the recent Shanghai lockdown as a good example of the power of memes. It is possible that the Chinese authorities were genuinely convinced that the Wuhan lockdown of 2020 demonstrated that restrictions work (in different terms, they remained infected with the relative meme). So, facing a new wave of the COVID virus, they reacted in the same way: with a new lockdown, convinced that they are doing their best to help Chinese citizens to overcome a real threat. 

If this is true, the Chinese authorities -- and the Chinese citizens, as well -- y must have been surprised when they saw that the new Covid wave refused to be flattened, as it had seemed to be during the Wuhan lockdown. The problem, at this point, lies with the stubbornness of memes, especially in the minds of politicians. A politician, in China as everywhere else, can never admit to having been wrong. When they find that some of their actions don't lead to the expected results, they tend to double down. Of course, a larger dose of a bad remedy does not usually help, but it is the way the human mind works. We may imagine that the leaders of the inhabitants of Easter Island did the same when they increased the effort in building large statues there. Incidentally, these statues were themselves another stubborn meme infecting a population.


Conclusion: a memetic cascade

Two years of the pandemic are summarized in a single graphic from "Worldometers." What you see is a series of seasonal peaks, one in the summer for the Southern Hemisphere, the other in winter for the Northern Hemisphere. There is no evidence that the various campaigns of non-pharmaceutical interventions had a significant effect. Every day in the world, some 150,000 persons die for all reasons. The graph tells us that, on the average, only about 7-8 thousand people died of (or perhaps just with) Covid every day. Even assuming that all those who died with Covid can be classified as dead from Covid (not obvious at all), more than 95% of the people who died during this period died for reasons other than the Covid. 

The question that we face, then, is how was it that the world reacted with such extreme measures to a threat that, seen today, was much exaggerated. It may be still too early to understand exactly what happened, but I think it is possible to propose that it was a typical "feedback cascade" in the world's memesphere. A convergence of parallel views from politicians, decision-makers, industrial lobbies, and even simple citizens, most of them truly convinced that they were doing the right thing. 

I don't mean here that there were no conspiracies in this story, in the sense of groups of people acting to exploit the pandemic for their personal economic or political interests. Lobbies and individuals do ride memes for their own advantage. So, when the pharmaceutical industry discovered that they could make money with vaccines against the Covid, they pushed hard for the meme to spread. The surveillance industry did the same. And governments, of course, pushed for more control over their citizens. They are naturally authoritarian and the Chinese government may not be especially more authoritarian than the Western ones. 

But, overall, memes can be a force that moves infected people even against their personal interests. My grandmother had no advantage, just a slightly higher cost, from her habit of boiling her milk before drinking it. It is much worse for the Covid story. A lot of ordinary people fully believed the memes that the government's propaganda machine was pushing and they did things that were positively harming them, physically, socially, and economically. They still do, memes are resilient. Daniel Dennett said that "a human being is an ape infested with memes." and the Covid story shows that it is true. 

Fortunately, the number of cases in China seems to have reached its peak and from now on, it can only go down. But the recent news from Shanghai is worrisome. If the Western media are to be trusted, the Chinese government is engaged in fencing apartment buildings to keep people locked inside. It may still be way too early to say that the time of the requiem for an old meme has come. 


See also the work by Jeffrey Tucker, and Chuck Pezeshky.



Note added after publication. Latest news from China (May 9th, 2022):

https://www.9news.com.au/world/china-zero-covid-policy-shanghai-xi-jinping-warning-coronavirus-asia-news/372e4151-b679-4cc6-85d7-34bf0d7040e8

"Our prevention and control strategy is determined by the party's nature and mission, our policies can stand the test of history, our measures are scientific and effective," the seven-member committee said, according to government news agency Xinhua.

"We have won the battle to defend Wuhan, and we will certainly be able to win the battle to defend Shanghai," it said.

They have clearly realized that they made a huge mistake, but they cannot admit that and they cannot back down. The usual disaster. And, by the way, they completely confirm my interpretation that they really believed that the lockdown in Wuhan had been a success in eradicating the virus. ("our measures are scientific" -- yeah, sure.....)

Sunday, April 24, 2022

Earth's Past and Future: a Long-Term View

 

For the Orthodox Easter day of 2022, I thought to abandon the daily noise of the news and take a long-term view. So, here is a post, republished from "The Proud Holobionts," that presents the history of our planet during the past 400 million years and some hypotheses on what could happen in the next billion years or so. Easter is a time of rebirth and of hope, so let's hope for a future of peace for these poor savanna monkeys, so noisy and so unruly. 


Gaia and the Savanna Monkeys. 

The Great Cycle of Earth's Forests




 Forests appeared on Earth some 400 million years ago, and they have been thriving over that long period. But, during the past 150 million years, they started to show signs of distress, reacting to the decline in atmospheric CO2 concentrations and to the competition with grasslands. As Earth changes, will forests be able to cope and survive? It is an extremely slow trend, but we cannot rule out that forests will conclude their cycle and disappear in a geologically short time. This text is an attempt to reconstruct the story of forests, and not just of foreste, and to imagine what their future could be in deep time. (image courtesy of Chuck Pezeshky


A forest is a magnificent, structured, and functional entity where the individual elements -- trees -- work together to ensure the survival of the ensemble. Each tree pumps water and nutrients all the way to the crown by the mechanism called evapotranspiration. The condensation of the evaporated water triggers the phenomenon called the "biotic pump" that benefits all the trees by pumping water from the sea. Each tree cycles down the carbohydrates it manufactures using photosynthesis to its mycorrhizal space, the underground system of roots and fungi that extracts mineral nutrients for the tree. The whole "rhizosphere" -- the root space -- forms a giant brain-like network that connects the trees to each other, sometimes termed "the Wood Wide Web." It is an optimized environment where almost everything is recycled. We can see it as similar to the concept of "just in time manufacturing" in the human economy. 

Forests are wonderful biological machines, but they are also easily destroyed by fires and attacks by parasites. And forests have a competitor: grass, a plant that tends to replace them whenever it has a chance to. Areas called savannas are mainly grass, although they host some trees. But they don't have a closed canopy, they don't evapotranspirate so much as forests, and they tend to exist in much drier climate conditions. Forests and grasslands are engaged in a struggle that may have started about 150 million years ago when grass appeared for the first time. During the past few million years, grasses seem to have gained an edge in the competition, in large part exploiting their higher efficiency in photosynthesis (the "C4" pathway) in a system where plants are starved for CO2.

Another competitor of forests is a primate that left its ancestral forest home just a couple of million years ago to become a savanna dweller -- we may call it the "savanna monkey," although it is also known as "Homo," or "Homo sapiens." These monkeys are clever creatures that seem to be engaged mainly in razing forests to the ground. Yet, in the long run, they may be doing forests a favor by returning the atmospheric CO2 concentration to values more congenial to the old "C3" photosynthetic mechanism still used by trees. 

Seen along the eons, we have an extremely complex and fascinating story. If forests have dominated Earth's landscape for hundreds of millions of years, one day they may disappear as Gaia gets old. In this post, I am describing this story from a "systemic" viewpoint -- that is, emphasizing the interactions of the elements of the system in a long-term view (it is called also "deep time"). The post is written in a light mood, as I hope to be able to convey the fascination of the story also to people who are not scientists. I tried to do my best to interpret the current knowledge, I apologize in advance for the unavoidable omissions and mistakes in such a complex matter, and I hope you'll enjoy this post. 


The Origin of Forests: 400 million years ago

Life on Earth may be almost 4 billion years old but, since we are multicellular animals, we pay special attention to multicellular life. So, we tend to focus on the Cambrian period (542-488 million years ago), when multicellular creatures became common. But that spectacular explosion of life was all about marine animals. Vascular plants started colonizing the land only during the period that followed the Cambrian, the Ordovician, (485 - 443 million years ago)

To be sure, the Ordovician flora on land was far from impressive. As far as we know, it was formed mainly by moss and lichens, although lichens may be much older and precede the Cambrian. Algae may have eked a precarious life on rocks even much earlier. Mosses, just like lichens, are humble plants: they are not vascularized, they don't grow tall, and they surely can't compare with trees. Nevertheless, they could change the planetary albedo and perhaps contribute to the fertilization of the marine biota -- something that may be related to the spectacular ice ages of the Ordovician. It is a characteristic of the Earth system that the temperature of the atmosphere is related to the abundance of life. More life draws down atmospheric CO2, and that cools the planet. The Ordovician saw one of these periodic episodes of cooling with the start of the colonization of the land. (image from Wikipedia)

There followed another long period called the "Silurian" (444 – 419 My ago) when plants kept evolving but still remained of the size of small shrubs at most. Then, during the Devonian (419 -359 million years ago) we have evidence of the existence of wood. And not only that, the fossil record shows the kind of channels called "Xylem" that connect the roots to the leaves in a tree. These plants were already tall and had a crown, a trunk, and roots. By the following geological period, the Carboniferous (359 - 299 My ago), forests seem to have been widespread.  

A major feature of these ancient trees was the development of an association with fungi. Their roots formed what we call a "mycorrhizal" symbiotic system. The fungi receive carbohydrates that the tree manufactures using photosynthesis, while the tree receives from the fungi essential minerals, including nitrogen and phosphorous. We don't know the details of how this symbiotic relationship evolved over hundreds of millions of years but, below, you can see a hypothesis of how it could have happened. (Source) (in the figure, "AM" stands for "arbuscular mycorrhiza" - the oldest form of symbiotic fungi).




Another major evolutionary innovation that may have been already operating in the Paleozoic forests is the "biotic pump." As an effect of the pressure drop created by the condensation of evapotranspirated water, forests can create pump water vapor from the ocean and create the "atmospheric rivers" that bring water inland. That, in turn, creates the land rivers that bring that water back to the sea. As forests create their own climate, they can expand nearly everywhere. The image shows clouds created by condensation over the modern Amazon rainforest (source).  

If we could walk in one of those ancient forests, we would find the place familiar, but also a little dreary. No birds and not even flying insects, they evolved only tens of million years later. No tree-climbing animals: no monkeys, no squirrels, nothing like that. Even in terms of herbivores, we have no evidence of the kind of creatures we are used to, nowadays. Grass didn't exist, so herbivores may have subsisted on decaying plant matter, or perhaps on ferns. Lots of greenery but no flowers, they had not evolved yet. You see in the image (source) an impression of what an ancient forest of Cladoxylopsida could have looked like during the Paleozoic era.

The Paleozoic forests already had one of the characteristics of modern forests: fires. There had never been fires on Earth before for at least two good reasons: one was that there was not enough oxygen, and the other was that there was nothing flammable. But now, with the oxygen concentration increasing and plants colonizing the land, fires appeared, lighting up the night. They would remain a characteristic of the land biosphere for hundreds of millions of years.

Image Source. The "fire window" is the region of concentrations in atmospheric oxygen in which fires can occur. Note how during the Paleozoic, the concentration could be considerably larger than it is now. Fireworks aplenty, probably. Note also how there exist traces of fires even before the development of full-fledge trees, in the Devonian. Wood didn't exist at that time, but the concentration of oxygen may have been high enough to set dry organic matter on fire. 

Wildfires are a classic case of a self-regulating system. The oxygen stock in the atmosphere is replenished by plant photosynthesis but is removed by burning wood. So, fires tend to reduce the oxygen concentration and that makes fires more difficult. But the story is more complicated than that. Fires also tend to create "recalcitrant" carbon compounds, charcoal for instance, that are not recycled by the biosphere and tend to remain buried for long times -- almost forever. So, over very long periods, fires tend to increase the oxygen concentration in the atmosphere by removing CO2 from it. The conclusion is that fires both decrease and increase the oxygen concentration. How about that for a taste of how complicated the biosphere processes are? 


 The Mesozoic: Forests and Dinosaurs

At the end of the Paleozoic, some 252 million years ago, there came the great destruction. A gigantic volcanic eruption of the kind we call "large igneous province" (sometimes affectionately "LIP") took place in the region we call Siberia today. It was huge beyond imagination: think of an area as large as modern Europe becoming a lake of molten lava. (image source)

It spewed enormous amounts of carbon into the atmosphere in the form of greenhouse gases. That warmed the planet, so much that it almost sterilized the biosphere. It was not the first, but it was the largest mass extinction of the Phanerozoic age. Gaia is normally busy keeping Earth's climate stable, but sometimes she seems to be sleeping at the wheel -- or maybe she gets drunk or stoned. The result is one of these disasters.  

Yet, the ecosystem survived the great extinction and rebounded. It was now the turn of the Mesozoic era, with forests re-colonizing the land. Over time, the angiosperms ("flowering plants") become dominant over the earlier conifers. With flowers, forests may have been much noisier than before, with bees and all kinds of insects. Avian dinosaurs also appeared. They seem to have been living mostly on trees, just like modern birds. 

For a long period during the Mesozoic, the landscape must have been mainly forested. No evidence of grass being common, although smaller plants, ferns, for instance, were abundant. Nevertheless, the great evolution machine kept moving. During the Jurassic, a new kind of mycorrhiza system evolved, the "Ectomycorrhizae" which allowed better control of the mineral nutrients in the rhizosphere, avoiding losses when the plants were not active. This mechanism was typical of conifers that could colonize cold regions of the supercontinent of the time, the "Pangea."  

During the Mesozoic, the dinosaurs appeared and diffused all over the planet. You surely noted how the Jurassic dinosaurs were often bipedal (See the illustration showing an early form of Iguanodon). They are also called "ornithopods," it is a body plan that allows herbivorous creatures to eat leaves on the high branches of trees. A bipedal stance makes the creature able to stand up, balancing on its tail. Some dinosaurs chose a different strategy, developing very long necks for the same purpose: the brontosaurus is iconic in this sense even though, traditionally, it was shown half-submerged in swamps (the illustration is from the New York Tribune of 1919). That's a bit silly, if you think about that. Why should a semiaquatic creature need a long neck? Think of a hippo with the neck of a giraffe: it wouldn't work so well. 

A much better representation of long-necked dinosaurs came with the first episode of the "Jurassic Park" (1993) movie series, when a gigantic diplodocus eats leaves. At some moment, the beast rises on its hind legs, using the tail as further support. 

If you are a dinosaur lover (and you probably are if you are reading this post) seeing this scene must have been a special moment in your life. And, after having seen it maybe a hundred times, it still moves me. But note how the diplodocus is shown in a grassy environment with sparse trees: that's not realistic because grass didn't exist yet when the creature went extinct at the end of the Jurassic period, about 145 million years ago. 

To see grass and animals specialized in eating it, we need to wait for the Cretaceous (145-66 million years ago). Evidence that some dinosaurs had started eating grass comes from the poop of long-necked dinosaurs. That's a little strange because, if you are a grazer, the last thing you need is a long neck. But new body plants rapidly evolved during the Cretaceous.  The Ceratopsia were the first true grazers, also called "mega-herbivores". Heavy, four-legged beasts that lived their life keeping their head close to the ground. The Triceratopses gained a space in human fantasy as prototypical dinosaurs, and they are often shown in movies while fighting tyrannosauruses. You see that in Walt Disney's movie "Fantasia" (1940). It may have happened for real.


Note the heavy bone shield over the head. With so much weight on board, Trixie couldn't possibly rise on its hind legs to munch on leaves on tree branches. Note also the beak, it looks perfectly adapted for collecting grass. It means that the Cretaceous landscape was probably similar to our world. We don't know if there existed the kind of biome we call today "savanna" -- a mix of grass and trees, but surely the land was shared by forests and grass, each biome with its typical fauna. 



The Great Cooling and the Rise of C4 Grass

At the end of the Cretaceous period, 66 million years ago, a new large igneous province appeared in the Deccan region, in India. It generated another climate disaster with the associated mass extinction. Most dinosaurs were wiped out, except those we call "birds" today. A large meteorite also hit Earth at that time. It caused only minor damage but, millions of years later, it gave human filmmakers a subject to explore in many dramatic movies. 

In time, the Deccan LIP faded away, and the era that followed is called the "Cenozoic." The ecosystem recovered, forests re-colonized the land, and mammals and birds (the only survivors of the Dinosauria clade) fought to occupy the ecological niches left free by their old masters. The early Cenozoic was a warm period of lush forests that offered refuge to a variety of animals: birds made their nests in branches, while squirrels and other small mammals jumped from branch to branch, or lived at the bottom. It is during this period that primates evolved: the huge forests of those times offered refuge for a variety of species that had probably already developed sophisticated social behaviors.  

Grass also survived the end-Cretaceous catastrophe. As a result, some mammals evolved into new "megaherbivores" or "megafauna" that occupied the same ecological niche that the triceratopsides had colonized long before.  Here is a brontotherium, a large herbivorous mammal that lived some 37-35 million years ago, during the late Eocene period (image from BBC).

The megabeasts of the Cenozoic do not have the same fascination of the giant dinosaurs, but this creature has a nice-sounding name, and it looks like Shrek, the ogre of Spielberg's movie. Note how the beast is correctly shown walking on a grassy plain. The Eocene is supposed to have been mostly forested, but grass existed, too. The brontotherium was an opportunistic herbivore, apparently able to subsist on various kinds of food, not just grass. 

During the warm phase of the Cenozoic, Earth reached a maximum temperature around 55 million years ago, some 8-12 deg C higher than today. The concentration of CO2, too, was large. That is called the "early Eocene climatic optimum". It doesn't mean that this period was better than other periods in terms of climate, but it seems that Earth was mainly covered with lush forests and that the biosphere thrived.  

Then, the atmosphere started cooling. It was a descent that culminated at the Eocene-Oligocene boundary, about 34 million years ago, with a new mass extinction. It was a relatively small event in comparison to other, more famous, mass extinctions, but still noticeable enough that the Swiss paleontologist Hans Georg Stehlin gave it the name of the "Grande Coupure" (the big break) in 1910. One of the victims was the brontotherium -- too bad!

Unlike other cases, the extinction at the Grande Coupure was not correlated to the warming created by a LIP, but to rapid cooling. You see the "step" in temperature decline in the figure. 



Why the big cooling? The answer is not completely known. Surely, the cooling was correlated to a decline in the CO2 content in the atmosphere and that, in turn, may have been generated by the collision of the Indian plate with Eurasia. It was a gigantic geological event that generated the Himalayan mountain belt. It exposed huge amounts of fresh rock to the atmosphere, and the result was the removal of CO2 because of silicate erosion and weathering. The Himalaya hypothesis is one of those explanations that seem to make a lot of sense, but it has big problems

Another possible explanation is that Earth just outgassed less CO2 than before. The CO2 that plants need for their photosynthesis is generated mainly at the mid-oceanic ridges where the hot mantle (the molten rock layer below Earth's crust) outgasses it, as it has been doing for billions of years. It may well be that the mantle is getting a little colder over the eons, so it outgasses less CO2 than before. It may be true, but it seems to be a weak effect -- not enough to explain the CO2 decline of the Cenozoic.

In my opinion, the most likely hypothesis is that the CO2 concentration declined because of higher biological productivity not just on land, but also in the sea (as it seems to be implied in a recent study)
In other words, the early Cenozoic may have been so booming with life of all kinds that it absorbed more CO2 from the atmosphere than the mantle could replace by outgassing. The result was the cooling phase. The abrupt step at "Grande Coupure" may be related to the evolution of a specific life form: baleen whales, which changed the equilibria of the whole marine ecosystem, drawing down even more CO2 from the atmosphere.

This interpretation agrees with the fact that ice ages are often observed after LIPs. It may be one of the many cycles of the ecosphere. So, when a major LIP appears, the rise of CO2 is disastrous at the beginning but, in the long run, it gives the biosphere a chance to rebound and expand in a CO2 rich system.  Then, the rebound generates its own doom: the abundant biological productivity draws down CO2 from the atmosphere, cools the planet, and the system finds itself CO2-starved again. In this interpretation, the Eocene cooling and the Grande Coupure were long-term consequences of the Deccan LIP that had destroyed the dinosaurs, millions of years before. I hasten to note that this is just one of the several possible interpretations but, in my opinion, it makes a lot of sense.    

The Eocene cooling had profound effects on forests. First, the CO2 decline gave an advantage to those plants which utilized a more efficient photosynthesis mechanism called the "C4" pathway. Earlier on, the standard photosynthesis mechanism (called "C3") had evolved in an atmosphere rich in CO2. The C3 mechanism is efficient in processing carbon dioxide, but it is hampered by the opposite process called "photorespiration," which becomes important when the CO2 concentration is low. Using the C4 mechanism, plants can concentrate CO2 in the cells where photosynthesis occurs and avoid the losses by photorespiration. 

C4 plants appeared shortly after the Grande Coupure and diffused mainly in grasses, Trees, instead, didn't adopt the new mechanism. The explanation is subtle: photosynthesis needs water, and the process that goes on in leaves is strongly connected to the evapotranspiration mechanism. The C4 mechanism needs less water than the C3 one, so evapotranspiration is hampered. The result is that C4 trees could not be as tall as the ordinary C3 ones, and so they are not favored by natural selection in forests. In an atmosphere of very low CO2, forests are disadvantaged because of the higher photosynthesis efficiency of grasses. 

During the period that followed the Grande Coupure, temperatures and CO2 concentrations remained stable, but at relatively low levels. The result was that many forests disappeared, replaced by grasslands and savannas. Herbivorous species evolved teeth more specialized for grazing and became "mega-herbivorous" species. The landscape must have become similar to the modern one, with patches of forests alternating with savannas. 


A typical savanna ecosystem: the Tarangire national park in Tanzania. (Image From Wikipedia). Compare with the forest image at the beginning of this post. 


Despite the expansion of savannas, rainforests continued to exist in the tropical regions. Conifer forests kept a foothold in the Northern regions, helped by their Ectomycorrhiza system that avoided the runoff of nutrients in winter. The boreal forest is also called "Taiga." 

Then, a new cooling phase started, apparently a continuation of the previous trend: cooling begets more cooling. It was the beginning of the "Pleistocene," a period of unstable climate with ice ages and interglacials following each other, triggered by small oscillations in solar irradiation caused by the characteristics of Earth's orbit. These oscillations are called "Milankovich Cycles" -- they are not the cause of the ice ages, just triggers. (Image Source).




The oscillations are caused by ice having a built-in albedo feedback so that the more ice expands, the more sunlight is directly reflected into space. That causes the temperature to decline and ice to expand even more. Taken to its extreme consequences, this mechanism may lead to the "Snowball Earth" condition, with ice covering the whole planet's surface. It may have happened for real during the "Cryogenian" period, some 600 million years ago. Fortunately, there were mechanisms able to re-heat Earth and return it to the conditions we consider "normal." 

During the Pleistocene, the CO2 concentration in Earth's atmosphere plunged to very low levels, especially during the glacial periods, when it reached levels as low as around 150 parts per million (ppm). Earth may have inched close to a new snowball Earth but, fortunately, that didn't happen. In part, it may be because the sun, today, is about 5% hotter than it was during the Cryogenian. But we will never know how close Gaia got to freezing to death. 

During the Pleistocene, the advancing ice sheets swept away all plants, but even in non-glaciated areas, forests suffered badly.  Tropical rainforests didn't disappear, but they were much reduced in extension. In the North, most of the Eurasian boreal forests were replaced by the "mammoth steppe," a huge area that went from Spain to Kamchatka. where mammoths and other mega-herbivores roamed. 



It is not impossible that an ice age colder than the Pleistocene average could have led to the eventual extinction of the forests, completely replaced by grasses. But that didn't happen, and things were going to change again. 


The Rise of the Savanna Monkeys  

Primates are arboreal creatures that evolved in the warm environment of the Eocene forests. They used tree branches as a refuge, and they could adapt to various kinds of food. From the viewpoint of these ancient primates, the shrinking of the area occupied by tropical forests was a disaster. They were not equipped to live in savannas: slow on the ground, they would be just an easy lunch for the powerful predators of the time. Primates also never colonized the northern taiga. It was probably not because they couldn't live in cold environments (some modern monkeys can do that), but because they couldn't cross the "mammoth steppe" that separated Tropical forests from the Northern forests. So, "boreal monkeys" do not exist (actually, there is one, but it is not exactly a monkey!).  

Yet, during the Pleistocene, the shrinking of the tropical forests forced some monkeys to move into the savanna, leaving their comfortable living on tree branches. The Australopythecines, (image source) appeared about 4 million years ago. We may call them the first "savanna monkeys." The first creatures that we classify as belonging to the genus Homo, the homo habilis, appeared some 2.8 million years ago. They were also savanna dwellers. 

The savanna monkeys won the game of survival by means of a series of evolutionary innovations. They increased their body size for better defense, they developed an erect stance to have a longer field of view, they super-charged their metabolism by getting rid of their body hair and using profuse sweating for cooling, they developed complex languages to create social groups for collective defense, and they learned how to make stone tools adaptable to different situations. Finally, they developed a tool that no animal on Earth had mastered before: fire. Over a few hundred thousand years, they spread all over the world from their initial base in a small area of Central Africa. The savanna monkeys, now called "Homo sapiens," were a stunning evolutionary success. The consequences on the ecosystem were enormous.

First, the savanna monkeys exterminated most of the megafauna. The only large mammals that survived the onslaught were those living in Africa, where they had the time to adapt to the new predator as it evolved. For instance, the large ears of the African elephant are a cooling system destined to make elephants able to cope with the incredible stamina of human hunters. But in Eurasia, North America, and Australia, the arrival of the newcomers was so fast and so unexpected that most of the large animals were wiped out. 

By eliminating the megaherbivores, the monkeys had, theoretically, given a hand to the competitors of grass, forests, which now had an easier time encroaching on grassland without seeing their saplings trampled. But the savanna monkeys had also taken the role of megaherbivores. They used fires with great efficiency to clear forests to make space for the game they hunted. In the book "1491" Charles Mann reports (. p 286) how "rather than domesticating animals for meat, Indians retooled ecosystems to encourage elk, deer, and bear. Constant burning of undergrowth increased the number of herbivores, the predators that fed on them, and the people who ate them both."  Later, as they developed metallurgy, the monkeys were able to cut down entire forests to make space for the cultivation of the grass species that they had domesticated meanwhile: wheat, rice, maize, oath, and many others. 

But the savanna monkeys were not necessarily enemies of the forests. In parallel to agriculture, they also managed entire forests as food sources. The story of the chestnut forests of North America is nearly forgotten today but, about one century ago, the forests of the region were largely formed of chestnut trees planted by Native Americans as a source of food (image source). By the start of the 20th century, the forest was devastated by the "chestnut blight," a fungal disease that came from China. It is said that some 3-4 billion chestnut trees were destroyed and, now, the chestnut forest doesn't exist anymore. The American chestnut forest is not the only example of a forest managed, or even created, by humans. Even the Amazon rainforest, sometimes considered an example of a "natural" forest, shows evidence of having been managed by the Amazonian Natives in the past as a source of food and other products. 

The action of the savanna monkeys was always massive and, in most cases, it ended in disaster. Even the oceans were not safe from the monkeys: they nearly managed to exterminate the baleen whales, turning large areas of the oceans into deserts. On land, entire forests were razed to the ground. Desertification ensued, brought upon by "megadroughts" when the rain cycle was no more controlled by the forests. Even when the monkeys spared a forest, they often turned it into a monoculture, subjected to be destroyed by pests, as the case of the American chestnuts shows. Yet, in a certain sense, the monkeys were making a favor to forests. Despite the huge losses to saws and hatchets, they never succeeded in completely exterminating a tree species, although some are critically endangered nowadays. 

The most important action of the monkeys was their habit of burning sedimented carbon species that had been removed from the ecosphere long before. The monkeys call these carbon species "fossil fuels" and they have been going on an incredible burning bonanza using the energy stored in this ancient carbon without the need of going through the need of the slow and laborious photosynthesis process. In so doing, they raised the concentration of CO2 in the atmosphere to levels that had not been seen for tens of millions of years before. That was welcome food for the trees, which are now rebounding from their former distress during the Pleistocene and reconquering the lands they had lost to grass. In the North of Eurasia, the Taiga is expanding and gradually eliminating the old mammoth steppe. Areas that today are deserts are likely to become green. We are already seeing the trend in the Sahara desert. 

What the savanna monkeys could do was probably a surprise for Gaia herself, who must be now scratching her head and wondering what has happened to her beloved Earth. And what's going to happen now?  


The New Large Igneous Province made by Monkeys

The giant volcanic eruptions called LIPs tend to appear with periodicities of the order of tens or hundreds of million years. But nobody can predict a LIP and, instead, the savanna monkeys engaged in the remarkable feat of creating a LIP-equivalent by burning huge amounts of organic ("fossil") carbon that had sedimented underground over tens or hundreds of millions of years of biological activity. 

It is remarkable how rapid the monkey LIP (MLIP) has been. Geological LIPS typically span millions of years. The MLIP went through its cycle in a few hundreds of years. It will be over when the concentration of fossil carbon stored in the crust will become too low to self-sustain the combustion with atmospheric oxygen. Just like all fires, the great fire of fossil carbon will end when it runs out of fuel, probably in less than a century from now. Even in such a short time, the concentration of CO2 is likely to reach, and perhaps exceed, levels never seen after the Eocene, some 50 million years ago.  

There is always the possibility that such a high carbon concentration in the atmosphere will push Earth over the edge of stability and kill Gaia by overheating the planet. But that's not a very interesting scenario, so let's examine the possibility that the biosphere will survive the carbon pulse. What's going to happen to the ecosphere?

The savanna monkeys are likely to be the first victims of the CO2 pulse that they themselves generated. Without the fossil fuels they had come to rely on, their numbers are going to decline very rapidly. From the incredible number of 8 billion individuals, they may return to levels typical of their early savanna ancestors: maybe just a few tens of thousands. Quite possibly, they'll go extinct. In any case, they will hardly be able to keep their habit of razing down entire forests. Without monkeys engaged in the cutting business and with high concentrations of CO2, forests are advantaged over savannas, and they are likely to recolonize the land. We are going to see again a lush, forested planet where arboreal monkeys will probably survive and thrive. Nevertheless, savannas will not disappear. They are part of the ecosystem, and new megaherbivores will evolve in a few hundreds of thousands of years. 

Over deep time, the great cycle of warming and cooling may restart after the monkey LIP, just as it does for geological LIPs. In a few million years, Earth may be seeing a new cooling cycle that will lead again to a Pleistocene-like series of ice ages. At that point, new savanna monkeys may evolve. They may restart their habit of exterminating the megafauna, burning forests, and building things in stone. But they won't have the same abundance of fossil fuel that the monkeys called "Homo sapiens" found when they emerged into the savannas. So, their impact on the ecosystem will be smaller, and they won't be able to create a new monkey-LIP. 

And then what? In deep time, the destiny of Earth is determined by the slowly increasing solar irradiation that is going, eventually, to eliminate the oxygen from the atmosphere and sterilize the biosphere, maybe in less than a billion years from now. So, we may be seeing more cycles of warming and cooling before Earth's ecosystem collapses. At that point, there will be no more forests, no more animals, and only single-celled life may persist. It has to be. Gaia, poor lady, is doing what she can to keep the biosphere alive, but she is not all-powerful. And not immortal, either. 

Nevertheless, the future is always full of surprises, and you should never underestimate how clever and resourceful Gaia is. Think of how she reacted to the CO2 starvation of the past few tens of millions of years. She came up with not just one, but two brand-new photosynthesis mechanisms designed to operate at low CO2 concentrations: the C4 mechanism typical of grasses, and another one called crassulacean acid metabolism (CAM). To say nothing about how the fungal-plant symbiosis in the rhizosphere has been evolving with new tricks and new mechanisms. You can't imagine what the old lady may concoct in her garage together with her Elf scientists (those who also work part-time for Santa Claus). 

Now, what if Gaia invents something even more radical in terms of photosynthesis? One possibility would be for trees to adopt the C4 mechanism and create new forests that would be more resilient against low CO2 concentrations. But we may think of even more radical innovations. How about a light fixation pathway that doesn't just work with less CO2, but that doesn't even need CO2? That would be nearly miraculous but, remarkably, that pathway exists. And it has been developed exactly by those savanna monkeys who have been tinkering -- and mainly ruining -- the ecosphere. 

The new photosynthetic pathway doesn't even use carbon molecules but does the trick with solid silicon (the monkeys call it "photovoltaics"). It stores solar energy as excited electrons that can be kept for a long time in the form of reduced metals or other chemical species. The creatures using this mechanism don't need carbon dioxide in the atmosphere, don't need water, they may get along even without oxygen. What the new creatures can do is hard to imagine for us (although we may try). In any case, Gaia is a tough lady, and she may survive much longer than we may imagine, even to a sun hot enough to torch the biosphere to cinders. Forests, too, are Gaia's creatures, and she is benevolent and merciful (not always, though), so she may keep them with her for a long, long time. (and, who knows, she may even spare the Savanna Monkeys from her wrath!). 


We may be savanna monkeys, but we remain awed by the majesty of forests. The image of a fantasy forest from Hayao Miyazaki's movie, "Mononoke no Hime" resonates a lot with us. But can you see the mistake in this image? What makes this forest not a real forest? 


__________________________



Note: You always write what you would like to read, and that's why I wrote this post. But, of course, this is a work in progress. I am tackling a subject so vast that I can't possibly hope to be sufficiently expert in all its facets to avoid errors, omissions, and wrong interpretations. Corrections from readers who are more expert than me are welcome! I would also like to thank Anastassia Makarieva for all she taught me about the biotic pump and about forests in general, and Mihail Voytehov for his comments about the rhizosphere. Of course, all mistakes in this text here are mine, not theirs.



Sunday, April 17, 2022

Veritatem Dies Aperit: Time Reveals the Truth

 


The Resurrection of Christ -- by Piero della Francesca (ca. 1465 AD).


The Roman Philosopher Lucius Annaeus Seneca lived in difficult times, not unlike ours. Then, as now, a Great Empire was starting to follow a road that would eventually lead to its final collapse. That was clear for those who could see beyond the veil of lies that pervaded everything, then as now. 

Seneca could never really face the ultimate consequences of what he was seeing, but sometimes he peered into the future, and he saw a better world that was to come. In his "De Ira" (about rage), Seneca wrote "Dandum semper est tempus: veritatem dies aperit." (There is always time, and the days disclose the truth). 

Seneca was also a contemporary of Jesus Christ. It is likely that neither knew of each other, but they shared one thing: the need for truth. Christ went beyond Seneca when he said, "I am the way, the truth, and the life." Seneca was still a man of the past, Christ was the future. 

There will be a moment when the mass of lies that surround us will collapse and fade away. On the day of resurrection, the day of Easter in Christianity, truth is revealed, and we might discover that it was always in front of us. 

Happy Easter, everyone! 


Monday, April 11, 2022

Descending to Hell: What's Happening to Humankind?

 

Shanghai residents locked inside their apartments, venting their rage by screaming in the night.  


This is truly beyond the pale. The wave of madness that descended upon us during the past two years was already unbelievable as it was. But it is getting worse. Much worse. The Shanghai lockdown has no justification whatsoever: 90% of the people who tested positive show no symptoms, and worldometer reports zero mortality. Maybe it is not exactly zero, but compared to one billion and a half Chinese people, you can surely take that number as a good approximation. 

What we are seeing has nothing to do with containing an epidemic. We don't know what the people are screaming, it may be rage, they may be cheering at each other. Impossible to say, but the scene looks like the starting scene of a horror movie, with the zombies locked inside their cages, rattling at the bars while trying to escape. I read that sometimes it happens in jail that the inmates start screaming together, rhythmically. It is like that, just on a much larger scale, the entire city of Shanghai. Has the whole world became a jail? It looks like a scientific experiment with rats. Have we become rats? Have we descended to Hell? What is left of human dignity? Human rights? Human life? 

We seem to have overcome some kind of unknown threshold. There had never been 8 billion people on Earth. And 8 billion people had never been connected in a single planetary communication network. Nobody can know what may happen when something that had never happened before happens. 

The impression is that the whole system is going unstable. If you see humankind as a complex system, then you know that moves as the result of a tangle of internal feedback effects. And we know that when a system is sufficiently large, feedbacks can perversely gang up together to collaborate in bringing the system down. It is the essence of the Seneca Effect (growth is sluggish, but ruin is rapid). 

In this case, the system may simply have become too big to be under anyone or anything's control. The feedbacks are untangling themselves, by themselves, like in a giant Jenga tower starting to fall. The immense creature quivers, moves, oscillates, bumps up and down as it mashes information flows that push it in one direction or another. It is a planetary-sized zombie. It doesn't know where it is going, it just moves on, crushing everything it steps on. 

And now what? We don't know. Nobody knows. But the same Seneca who said that "ruin is rapid" also said that "veritatem dies aperit," or "time discloses the truth." There will be better times in the future. There always are.