[{"data":1,"prerenderedAt":1811},["ShallowReactive",2],{"evidence-index":3,"evidence-doc-the-unity":511},[4,19,35,48,61,74,93,106,117,129,141,153,164,175,192,207,217,235,246,259,278,300,326,343,353,375,385,407,417,427,439,448,459,471,485,496],{"path":5,"title":6,"description":7,"keywords":8,"field":17,"order":18},"\u002Fevidence\u002Fmaxwells-equations","Maxwell's Equations","Four equations that joined electricity, magnetism and light, and set physics on the road to relativity.",[9,10,11,12,13,14,15,16],"electromagnetism","electric fields","magnetic fields","electromagnetic waves","light","Gauss law","Faraday law","Ampere law","Physical",1,{"path":20,"title":21,"description":22,"keywords":23,"field":34,"order":18},"\u002Fevidence\u002Fnumerology-origin","Numerology Origin","How ancient number symbolism, built to describe cosmic order and interpret sacred texts, became modern personality numerology.",[24,25,26,27,28,29,30,31,32,33],"number symbolism","Pythagoras","gematria","sacred numbers","divination","history of mathematics","tetractys","monad","decad","perfect number","Cultural",{"path":36,"title":37,"description":38,"keywords":39,"field":47,"order":18},"\u002Fevidence\u002Forigin-of-life","Origin of Life","What chemistry, geology and genomics currently tell us about how non-living matter became the first living cells.",[40,41,42,43,44,45,46],"abiogenesis","RNA world","Miller-Urey experiment","prebiotic chemistry","hydrothermal vents","protocells","LUCA","Biological",{"path":49,"title":50,"description":51,"keywords":52,"field":34,"order":18},"\u002Fevidence\u002Fsuffering","Suffering","How Siddhartha Gautama tested both luxury and severe self-denial, and what his diagnosis of suffering became.",[53,54,55,56,57,58,59,60],"Buddhism","Buddha","Siddhartha Gautama","dukkha","Four Noble Truths","Middle Way","Eightfold Path","craving",{"path":62,"title":63,"description":64,"keywords":65,"field":73,"order":18},"\u002Fevidence\u002Fthe-evolution-of-trust","The Evolution of Trust","How the prisoner's dilemma, Axelrod's tournaments, and later models explain when cooperation beats selfishness, and when it does not.",[66,67,68,69,70,71,72],"game theory","prisoners dilemma","cooperation","Robert Axelrod","tit for tat","reciprocity","evolutionary dynamics","Social",{"path":75,"title":76,"description":77,"keywords":78,"field":73,"order":92},"\u002Fevidence\u002Fcivil-disobedience","Civil Disobedience","How Gandhi turned a refusal to obey into a political force, why open, nonviolent law-breaking works more often than violence, and where it fails.",[79,80,81,82,83,84,85,86,87,88,89,90,91],"civil disobedience","Gandhi","satyagraha","Salt March","nonviolence","ahimsa","Thoreau","Martin Luther King","non-cooperation","nonviolent resistance","Chenoweth","Orwell","wu wei",2,{"path":94,"title":95,"description":96,"keywords":97,"field":105,"order":92},"\u002Fevidence\u002Fplacebo","Placebo","How an inert treatment can change pain, symptoms and brain chemistry, why it works, and where its power ends.",[98,99,100,101,102,103,104],"placebo effect","nocebo","expectation","conditioning","pain relief","clinical trials","endogenous opioids","Mind",{"path":107,"title":108,"description":109,"keywords":110,"field":105,"order":92},"\u002Fevidence\u002Fpuer-aeternus","Puer Aeternus","The Jungian \"eternal youth\" archetype, what it describes, what empirical psychology can and cannot say about it, and where such people thrive or struggle.",[111,112,113,114,115,116],"Carl Jung","Jungian psychology","eternal youth","archetype","Peter Pan","adulthood",{"path":118,"title":119,"description":120,"keywords":121,"field":34,"order":92},"\u002Fevidence\u002Ftaoism","Taoism","What the Dao, wu wei and naturalness mean, and why Daoist texts separate caring for something from clinging to it.",[122,123,124,125,126,91,127,128],"Daoism","Laozi","Zhuangzi","Daodejing","Tao Te Ching","yin and yang","attachment",{"path":130,"title":131,"description":132,"keywords":133,"field":17,"order":92},"\u002Fevidence\u002Ftime-dilation","Time Dilation","Why moving clocks and clocks deeper in gravity tick slower, and how the twin paradox resolves.",[134,135,136,137,138,139,140],"special relativity","general relativity","twin paradox","Lorentz factor","proper time","atomic clocks","GPS",{"path":142,"title":143,"description":144,"keywords":145,"field":17,"order":152},"\u002Fevidence\u002Fhiggs-field","Higgs Field","How an invisible field filling all of space gives mass to fundamental particles, and how it was found in 2012.",[146,147,148,149,150,151],"Higgs boson","particle physics","Standard Model","CERN","Large Hadron Collider","symmetry breaking",3,{"path":154,"title":155,"description":156,"keywords":157,"field":105,"order":152},"\u002Fevidence\u002Fmeditation","Meditation","What meditation trains, how it seems to work in the brain, and how strong the evidence really is.",[158,159,160,161,162,163],"mindfulness","attention","neuroscience","brain","stress","contemplative practice",{"path":165,"title":166,"description":167,"keywords":168,"field":34,"order":152},"\u002Fevidence\u002Fthe-god-of-the-gaps","The God of the Gaps","Why explaining unknowns by appeal to God keeps losing ground, and why many theologians reject the move themselves.",[169,170,171,172,173,174],"theology","religion and science","argument from ignorance","naturalism","cosmological argument","fine-tuning",{"path":176,"title":177,"description":178,"keywords":179,"field":105,"order":152},"\u002Fevidence\u002Fthe-illusion-of-free-will","The Illusion of Free Will","A machine that knows what you will choose, what physics and psychology say about the feeling of choosing, and why philosophers still disagree about whether free will exists.",[180,181,182,183,184,185,186,187,188,189,190,191],"free will","Newcomb's problem","Newcomb's paradox","predictor","Laplace's demon","compatibilism","illusionism","decision theory","one box","two boxes","Wegner","conscious will",{"path":193,"title":194,"description":195,"keywords":196,"field":205,"order":206},"\u002Fevidence\u002Fif-the-world-was-vegan","If the World Was Vegan","A scenario analysis of whether global agriculture could feed everyone without animals, and what it would mean for land, soil and ecosystems.",[197,198,199,200,201,202,203,204],"veganism","plant-based diet","agriculture","livestock","food security","soil fertility","biodiversity","nutrition","Prospective",4,{"path":208,"title":209,"description":210,"keywords":211,"field":17,"order":206},"\u002Fevidence\u002Fkaluza-klein-reduction","Kaluza–Klein Reduction","How one extra, curled-up dimension turns Einstein's gravity into gravity plus electromagnetism, and why we have not seen it.",[212,213,214,9,215,216],"extra dimensions","compactification","gravity","unification","charge quantization",{"path":218,"title":219,"description":220,"keywords":221,"field":73,"order":206},"\u002Fevidence\u002Fthe-weight-of-nothing","The Weight of Nothing","Why people shock themselves rather than sit alone with their thoughts, and why a mind given nothing starts producing something of its own.",[222,223,224,225,226,227,228,229,230,231,232,233,234],"boredom","disengaged mind","Just think","Timothy Wilson","electric shock","sensory deprivation","white torture","solitary confinement","hallucination","Ganzfeld","predictive processing","Amnesty International","Iran",{"path":236,"title":237,"description":238,"keywords":239,"field":17,"order":245},"\u002Fevidence\u002F13-dimensional-models","13-Dimensional Models","Where the number 13 comes from in theoretical physics, why a universe with two time dimensions is mathematically possible, and why none of it is confirmed.",[240,241,242,243,212,244,213],"string theory","M-theory","F-theory","S-theory","two-time physics",5,{"path":247,"title":248,"description":249,"keywords":250,"field":34,"order":245},"\u002Fevidence\u002F1984","1984","What Orwell's Nineteen Eighty-Four is about, why he wrote it, and why rival governments have banned or challenged it as propaganda for the other side.",[251,252,253,254,255,256,257,258],"George Orwell","Nineteen Eighty-Four","dystopia","totalitarianism","surveillance","Big Brother","Newspeak","censorship",{"path":260,"title":261,"description":262,"keywords":263,"field":47,"order":245},"\u002Fevidence\u002Fsentience","Sentience","What it means for a being to feel, how science tests it in animals from crabs to oysters, and why a simpler mind does not mean a smaller capacity to suffer.",[264,265,266,267,268,269,270,271,272,273,274,275,276,277,197],"sentience","consciousness","animal consciousness","animal pain","oyster","bivalves","hermit crabs","octopus","insects","hard problem","soul","moral status","Cambridge Declaration","New York Declaration",{"path":279,"title":280,"description":281,"keywords":282,"field":73,"order":245},"\u002Fevidence\u002Fsouffle-de-riche","Soufflé de Riche","Why suffering in 1789 stopped being something to endure and became evidence against the system, and where that pressure goes in societies today.",[283,284,285,286,287,288,289,290,291,292,293,294,295,296,297,298,299],"French Revolution","Marie Antoinette","let them eat cake","brioche","Rousseau","eat the rich","tax the rich","legitimacy","inequality","cahiers de doléances","Estates-General","Tennis Court Oath","Bastille","relative deprivation","collective action","preference falsification","political trust",{"path":301,"title":302,"description":303,"keywords":304,"field":73,"order":325},"\u002Fevidence\u002Fimpermanent-solution","Impermanent Solution","How the Phoebus cartel engineered lightbulbs to fail on schedule, and what happens when durability and revenue stop pointing the same way.",[305,306,307,308,309,310,311,312,313,314,315,316,317,318,319,320,321,322,323,324],"planned obsolescence","Phoebus cartel","lightbulb","1000 hours","Centennial Light","Livermore","Osram","Philips","General Electric","Tungsram","durability","repairability","right to repair","e-waste","spare parts","software support","ecodesign","survivorship bias","incentives","circular economy",6,{"path":327,"title":328,"description":329,"keywords":330,"field":34,"order":325},"\u002Fevidence\u002Fliving-hell","Living Hell","How an exiled Florentine built Hell from theology, Aristotle and politics, and why its punishments read like the loops people build while alive.",[331,332,333,334,335,336,337,338,339,340,341,342],"Dante Alighieri","Inferno","Divine Comedy","nine circles","contrapasso","exile","Florence","Lucifer","Cocytus","Aristotle","rumination","psychology",{"path":344,"title":345,"description":346,"keywords":347,"field":17,"order":325},"\u002Fevidence\u002Ftachyons","Tachyons","Hypothetical particles that always move faster than light, why they would carry messages into the past, and why modern physics reads them as a sign of instability instead.",[348,349,350,351,352,134],"faster than light","superluminal","causality","imaginary mass","instability",{"path":354,"title":355,"description":356,"keywords":357,"field":47,"order":325},"\u002Fevidence\u002Fthe-unity","The Unity","Why the line between one organism and many is blurrier than it looks, from ancient bacteria in our cells to viral genes in the placenta to the question of whether Earth is alive.",[358,359,360,361,362,363,364,365,366,367,368,369,370,371,372,373,374,203],"Gaia hypothesis","James Lovelock","Lynn Margulis","living Earth","symbiosis","endosymbiosis","mitochondria","microbiome","holobiont","hologenome","endogenous retroviruses","syncytin","placenta","biological individuality","biosphere","planetary boundaries","climate change",{"path":376,"title":377,"description":378,"keywords":379,"field":17,"order":384},"\u002Fevidence\u002Fclosed-timelike-curves","Closed Timelike Curves","How Einstein's equations permit paths through spacetime that return to their own past, and why no one has ever found one.",[380,135,350,381,382,383],"time travel","wormholes","Godel","chronology protection",7,{"path":386,"title":387,"description":388,"keywords":389,"field":47,"order":384},"\u002Fevidence\u002Fperfectly-deprecated","Perfectly Deprecated","How a trait can be almost perfectly adapted to one world and turn harmful in the next, without the organism changing at all.",[390,391,392,393,394,395,396,397,398,399,400,401,402,403,404,405,406],"evolutionary mismatch","maladaptation","adaptive lag","lag load","ecological trap","evolutionary trap","flightlessness","island birds","dodo","kakapo","sea turtle hatchlings","light pollution","seafinding","natural selection","rapid environmental change","aggression","human evolution",{"path":408,"title":409,"description":410,"keywords":411,"field":17,"order":416},"\u002Fevidence\u002Fnovikov-self-consistency-principle","Novikov Self-Consistency Principle","Why a journey into the past might never change it, and why that need not require any force preventing change.",[380,412,413,414,350,415],"grandfather paradox","causal loops","closed timelike curves","consistency",8,{"path":418,"title":419,"description":420,"keywords":421,"field":17,"order":426},"\u002Fevidence\u002Fbootstrap-paradox","Bootstrap Paradox","Causal loops in which an object or idea exists only because it was carried into its own past, and whether physics can tolerate them.",[380,422,423,350,424,425],"causal loop","information paradox","entropy","self-consistency",9,{"path":428,"title":429,"description":430,"keywords":431,"field":17,"order":438},"\u002Fevidence\u002Fblock-universe","Block Universe","The view, motivated by relativity, that past, present and future all exist and time does not flow.",[432,433,434,435,436,437],"eternalism","spacetime","relativity","simultaneity","presentism","arrow of time",10,{"path":440,"title":441,"description":442,"keywords":443,"field":17,"order":447},"\u002Fevidence\u002Fdeterminism","Determinism","Whether the present fixes the entire future, what physics says about it, and why free will may survive either way.",[180,350,444,185,445,446],"Laplace demon","chaos","quantum mechanics",11,{"path":449,"title":450,"description":451,"keywords":452,"field":17,"order":458},"\u002Fevidence\u002Fbig-bounce","Big Bounce","The idea that our universe began not from nothing but from the collapse of a previous one, and what physics can and cannot say about it.",[453,454,455,456,424,457],"cosmology","Big Bang","cyclic universe","loop quantum cosmology","eternal return",12,{"path":460,"title":461,"description":462,"keywords":463,"field":17,"order":470},"\u002Fevidence\u002Fgolden-ratio","Golden Ratio","Why one number, the golden ratio, keeps turning up in sunflowers, and why many famous claims about it are myths.",[464,465,466,467,468,469],"phi","Fibonacci","phyllotaxis","spirals","irrational numbers","geometry",13,{"path":472,"title":473,"description":474,"keywords":475,"field":17,"order":484},"\u002Fevidence\u002Fsha-256-encryption","SHA-256 Hashing","How the SHA-256 hash function works, why it cannot be run backwards, and what reversing it would actually require.",[476,477,478,479,480,481,482,483],"cryptography","hash function","SHA256","encryption","preimage resistance","collisions","Bitcoin","brute force",14,{"path":486,"title":487,"description":488,"keywords":489,"field":17,"order":495},"\u002Fevidence\u002Fgrovers-algorithm","Grover's Algorithm","How a quantum computer can search N possibilities in about √N steps, and why that is both remarkable and far less than popular accounts claim.",[490,491,492,493,494,476],"quantum computing","quantum search","qubits","amplitude amplification","oracle",15,{"path":497,"title":498,"description":499,"keywords":500,"field":17,"order":510},"\u002Fevidence\u002Fentropy","Entropy","Why heat flows one way, how a thought experiment about a tiny demon tied physics to information, and whether black holes destroy it.",[424,501,502,503,504,505,506,437,507,508,509],"second law of thermodynamics","Maxwell's demon","Szilard engine","Landauer's principle","information","Boltzmann","black hole information paradox","Hawking radiation","unitarity",16,{"id":512,"title":355,"body":513,"description":356,"extension":1804,"field":47,"keywords":1805,"meta":1806,"navigation":1807,"order":325,"path":354,"seo":1808,"stem":1809,"__hash__":1810},"evidence\u002Fevidence\u002Fthe-unity.md",{"type":514,"value":515,"toc":1790},"minimark",[516,520,524,527,530,533,536,541,556,574,585,588,592,607,641,644,647,650,653,656,660,663,674,692,701,704,708,711,725,736,739,799,830,837,840,844,847,853,867,870,895,908,911,915,932,952,967,970,974,977,983,996,1002,1008,1023,1027,1030,1040,1043,1046,1062,1065,1069,1072,1075,1078,1093,1096,1100,1103,1129,1143,1146,1149,1152,1155,1158,1161,1164,1171,1174,1177,1180,1183,1186,1190,1210,1228,1247,1264,1283,1302,1321,1339,1358,1377,1396,1413,1431,1449,1467,1486,1505,1523,1541,1559,1576,1595,1612,1630,1648,1666,1682,1700,1719,1739,1755,1772],[517,518,355],"h1",{"id":519},"the-unity",[521,522,523],"p",{},"Is Earth alive?",[521,525,526],{},"Leave the question open for a moment and look at what the planet does. It takes in energy from the Sun and radiates heat back into space. It moves carbon, nitrogen, water and oxygen through air, rock, ocean and bodies, over and over. When it is disturbed, by a volcanic winter or an asteroid impact, it changes, and then it settles into new patterns. It holds millions of species feeding on, sheltering, poisoning and depending on one another. And for more than three billion years, through a Sun that has grown considerably brighter, its surface has stayed within the narrow range where liquid water and life can persist.",[521,528,529],{},"Energy in, matter cycled, response to disturbance, persistence over time. Described that way, the planet sounds uncomfortably like something with a metabolism.",[521,531,532],{},"Humans noticed this long before they could measure it. The Greeks named the Earth Gaia and made her the mother of the gods. The Andes have Pachamama, Vedic India had Prithvi, Māori tradition has Papatūānuku, Norse myth had Jörð. The details differ, but the intuition recurs: the ground under us is not just a surface but a body, and we are its children.",[521,534,535],{},"Mythology is not evidence. But in the twentieth century the intuition came back in scientific form.",[537,538,540],"h2",{"id":539},"the-planet-that-would-not-settle","The Planet That Would Not Settle",[521,542,543,544],{},"In the 1960s the chemist James Lovelock was working with NASA on a practical problem: how could a spacecraft tell whether Mars had life? His answer was to look at the atmosphere rather than the soil. A lifeless planet should drift toward chemical equilibrium, its gases reacting until nothing more happens. Earth's atmosphere does not. It holds oxygen and methane together, two gases that destroy each other, in amounts that only make sense if something keeps replenishing them. That something is life. ",[545,546,549,550,555],"sup",{"className":547},[548],"c-cite","[",[551,552,554],"a",{"href":553},"#ref-1","1","]",[521,557,558,559,562,563,570,571,573],{},"Lovelock pushed the idea further. If life keeps the atmosphere far from equilibrium, perhaps life also helps keep it within bounds suitable for life. In 1974 he and the microbiologist ",[560,561,360],"strong",{}," published the argument formally: the biosphere, together with the atmosphere, oceans and surface rocks, might behave as a self-regulating system that keeps conditions habitable. ",[545,564,549,566,555],{"className":565},[548],[551,567,569],{"href":568},"#ref-2","2"," They called it the ",[560,572,358],{},".",[521,575,576,577,584],{},"The early Sun is a good illustration of why the question was worth asking. Stellar physics says the young Sun shone roughly a quarter to a third less brightly than it does today, yet geological evidence shows liquid water on Earth's surface for most of that time. ",[545,578,549,580,555],{"className":579},[548],[551,581,583],{"href":582},"#ref-3","3"," Something kept the planet warm when it \"should\" have frozen. Much of the explanation involves greenhouse gases and a slow geological thermostat, the carbonate–silicate cycle, in which rock weathering removes carbon dioxide faster when the climate is warm. Life takes part in some of these cycles. Not all of the regulation is biological.",[521,586,587],{},"That last sentence matters, because it marks the line the Gaia hypothesis is often pushed across.",[537,589,591],{"id":590},"a-collection-is-not-a-creature","A Collection Is Not a Creature",[521,593,594,595,599,600],{},"The weak versions of Gaia are now ordinary science. Life clearly influences the chemistry of the atmosphere and oceans, and Earth-system science studies the feedbacks between them in detail. The strong versions are different. The claims that life regulates the planet ",[596,597,598],"em",{},"for its own benefit",", or that Earth is literally a single organism, drew sharp criticism. ",[545,601,549,603,555],{"className":602},[548],[551,604,606],{"href":605},"#ref-4","4",[521,608,609,610,617,618,621,622,629,630,633,634],{},"The central objection came from evolutionary biologists, notably W. Ford Doolittle and Richard Dawkins. Natural selection builds regulation into organisms because organisms reproduce, vary and compete; the ones that regulate badly leave fewer descendants. Earth has no population of rival planets and no offspring. So how could planetary self-regulation have been selected? ",[545,611,549,613,555],{"className":612},[548],[551,614,616],{"href":615},"#ref-5","5"," Lovelock and Andrew Watson answered with ",[560,619,620],{},"Daisyworld",", a toy model in which dark and light daisies, each simply growing where it grows best, end up stabilizing their planet's temperature without any foresight or planetary selection. ",[545,623,549,625,555],{"className":624},[548],[551,626,628],{"href":627},"#ref-6","6"," The model showed regulation ",[596,631,632],{},"can"," emerge from selfish parts. It did not show that Earth's real feedbacks work that way, and critics noted that feedbacks between life and climate can amplify change as easily as damp it. ",[545,635,549,637,555],{"className":636},[548],[551,638,640],{"href":639},"#ref-7","7",[521,642,643],{},"Margulis herself resisted the stronger reading. She did not describe Earth as one organism; she described it as an enormous web of interacting organisms whose combined activity produces regulation.",[521,645,646],{},"There is also a simpler objection, and it is hard to argue with.",[521,648,649],{},"A collection of living beings does not automatically make the thing containing them alive. A forest is full of life, but we do not normally call the forest an organism. An ocean is full of organisms, but the ocean itself is not therefore alive. Earth contains life. That alone does not make Earth a living creature.",[521,651,652],{},"Fair enough.",[521,654,655],{},"Now apply the same test to yourself.",[537,657,659],{"id":658},"a-crowd-called-a-person","A Crowd Called a Person",[521,661,662],{},"What you call \"one human being\" is already an enormous biological community.",[521,664,665,666,673],{},"A commonly repeated figure says bacterial cells in the body outnumber human cells ten to one. It came from a rough estimate made in the 1970s and was never measured properly. A careful recount in 2016 put a reference adult at about 30 trillion human cells and about 38 trillion bacteria, mostly in the colon. ",[545,667,549,669,555],{"className":668},[548],[551,670,672],{"href":671},"#ref-8","8"," The ratio is closer to one to one, and it can shift noticeably after a bowel movement. So the old number was wrong. But it was wrong in a way that leaves the basic point intact: in cell count, you are roughly half not-you.",[521,675,676,677,684,685],{},"These microbes are not simply contamination or passengers. Gut bacteria break down dietary fibres that human enzymes cannot, producing short-chain fatty acids that the cells lining the colon use as fuel. They synthesize some vitamins, transform bile acids and drugs, and compete with pathogens for space. ",[545,678,549,680,555],{"className":679},[548],[551,681,683],{"href":682},"#ref-9","9"," Animals raised completely germ-free develop abnormal immune systems, which shows that the immune system partly learns what it is by growing up alongside microbes. ",[545,686,549,688,555],{"className":687},[548],[551,689,691],{"href":690},"#ref-10","10",[521,693,694,695,700],{},"This should not be overstated. Not every microorganism in the body is essential, many are transient, and the composition differs enormously between healthy people. Much of the popular link between particular bacteria and particular diseases is correlation rather than established cause. ",[545,696,549,698,555],{"className":697},[548],[551,699,683],{"href":682}," The microbiome is a real participant in human physiology. It is not proof that a human is secretly a single superorganism.",[521,702,703],{},"But it raises a question the Earth objection did not expect. If a collection of organisms living together is not one organism, what exactly are you?",[537,705,707],{"id":706},"the-stranger-in-every-cell","The Stranger in Every Cell",[521,709,710],{},"The question goes deeper than the gut. It goes inside the cells that are unambiguously \"human\".",[521,712,713,714,716,717,724],{},"Almost every one of your cells contains hundreds to thousands of ",[560,715,364],{},", the structures that use oxygen to extract most of the energy from food. Early in the twentieth century a few biologists, among them Konstantin Mereschkowsky for chloroplasts and later Ivan Wallin for mitochondria, proposed that some of these structures had once been free-living microbes. ",[545,718,549,720,555],{"className":719},[548],[551,721,723],{"href":722},"#ref-11","11"," The idea was mostly dismissed. The tools to test it did not exist.",[521,726,727,728,735],{},"In 1967 Lynn Margulis, then publishing as Lynn Sagan, revived and expanded the argument. She proposed that mitochondria, chloroplasts and possibly other cell structures descended from bacteria that had been taken into ancestral cells and never left. ",[545,729,549,731,555],{"className":730},[548],[551,732,734],{"href":733},"#ref-12","12"," The paper was rejected many times before it was accepted, and the theory was controversial for years. What settled it was not persuasion but molecular biology, produced by many laboratories over the following decades.",[521,737,738],{},"The evidence converges from several directions:",[740,741,742,755],"table",{},[743,744,745],"thead",{},[746,747,748,752],"tr",{},[749,750,751],"th",{},"Feature of mitochondria",[749,753,754],{},"What it resembles",[756,757,758,767,775,783,791],"tbody",{},[746,759,760,764],{},[761,762,763],"td",{},"Their own DNA, separate from the nucleus",[761,765,766],{},"A bacterial chromosome, usually circular",[746,768,769,772],{},[761,770,771],{},"Reproduce by dividing in two",[761,773,774],{},"Bacterial fission",[746,776,777,780],{},[761,778,779],{},"Their own ribosomes",[761,781,782],{},"Bacterial ribosomes, not the cell's own",[746,784,785,788],{},[761,786,787],{},"Two surrounding membranes",[761,789,790],{},"A bacterium inside an engulfing membrane",[746,792,793,796],{},[761,794,795],{},"Gene sequences",[761,797,798],{},"A branch of the alphaproteobacteria",[521,800,801,802,809,810,822,823],{},"The first row was established in the 1960s, when mitochondrial DNA was seen directly. ",[545,803,549,805,555],{"className":804},[548],[551,806,808],{"href":807},"#ref-13","13"," The last is the strongest: when mitochondrial genes are compared with those of living organisms, they fall inside the bacterial family tree, nearest to a group called the alphaproteobacteria. ",[545,811,549,813,817,818,555],{"className":812},[548],[551,814,816],{"href":815},"#ref-14","14",",",[551,819,821],{"href":820},"#ref-15","15"," That mitochondria descend from a bacterial ancestor is now accepted theory, supported about as strongly as anything in evolutionary biology. How the partnership began, and what the host cell was, remain actively debated. ",[545,824,549,826,555],{"className":825},[548],[551,827,829],{"href":828},"#ref-16","16",[521,831,832,833,836],{},"Think about what this means. Something that was once an independent organism, with its own lineage and its own way of making a living, became so thoroughly integrated into another organism that we now call it an ",[560,834,835],{},"organelle",", a part. Over time most of its genes moved into the host's nucleus. It cannot survive on its own anymore, and the host cannot survive without it. You do not experience your mitochondria as guests. You experience them as yourself.",[521,838,839],{},"Margulis is the thread that ties the two halves of this article together. She spent the first part of her career arguing that apparently individual cells were products of ancient cooperation between organisms. She spent the later part, with Lovelock, asking whether similar cooperation and feedback operated at the scale of the planet. The first argument became textbook biology. The second remains contested. The same person, the same instinct, two very different levels of evidence.",[537,841,843],{"id":842},"fossils-in-the-genome","Fossils in the Genome",[521,845,846],{},"Go one level deeper, from the cell to the DNA itself.",[521,848,849,852],{},[560,850,851],{},"Retroviruses",", the family that includes HIV, reproduce by writing a copy of their genes into the DNA of the cell they infect. Usually that copy dies with the cell. But when a retrovirus infects a sperm or egg cell, or the cells that make them, the viral copy can be inherited. The infected animal's offspring carry it in every cell, and so do their offspring.",[521,854,855,856,858,859,866],{},"Over tens of millions of years this happened again and again to our ancestors. The initial sequencing of the human genome found that sequences of this retroviral type, called ",[560,857,368],{}," and their relatives, make up roughly 8% of human DNA. ",[545,860,549,862,555],{"className":861},[548],[551,863,865],{"href":864},"#ref-17","17"," For comparison, the genes that actually code for proteins make up less than 2%.",[521,868,869],{},"Most of this viral DNA does nothing obvious. The sequences have accumulated mutations, lost pieces, or been silenced by the cell. They are fossils: records of infections that ended long ago.",[521,871,872,873,875,876,883,884,887,888],{},"A few were put to work. In 2000 researchers identified a human protein essential to the placenta, named ",[560,874,369],{},", and found it was the envelope protein of an ancient retrovirus. ",[545,877,549,879,555],{"className":878},[548],[551,880,882],{"href":881},"#ref-18","18"," Viral envelope proteins are built to fuse the virus's membrane with a cell's membrane. In the placenta, syncytin fuses cells with each other, forming the ",[560,885,886],{},"syncytiotrophoblast",", the continuous layer where the mother's blood and the fetus exchange nutrients and gases. Mice lacking their own version of the gene fail to form a normal placenta and the embryos die. ",[545,889,549,891,555],{"className":890},[548],[551,892,894],{"href":893},"#ref-19","19",[521,896,897,898,901,902,907],{},"The pattern is stranger still. Different mammalian lineages, primates, rodents, rabbits, carnivores and others, captured ",[596,899,900],{},"different"," retroviral envelope genes at different times and co-opted each for the same job. ",[545,903,549,905,555],{"className":904},[548],[551,906,894],{"href":893}," Evolution borrowed the same kind of viral tool repeatedly.",[521,909,910],{},"So part of the biological machinery that lets humans make new humans came from viruses that infected our distant ancestors. The organ that marks the boundary between a mother and a child was built partly from a boundary-crossing parasite.",[537,912,914],{"id":913},"the-holobiont-and-its-critics","The Holobiont and Its Critics",[521,916,917,918,920,921],{},"Biologists have a word for an organism taken together with the microbes that live on and in it: a ",[560,919,366],{},". Margulis used it in 1991, and it has since become common in the study of corals, insects, plants and animals. ",[545,922,549,924,817,928,555],{"className":923},[548],[551,925,927],{"href":926},"#ref-20","20",[551,929,931],{"href":930},"#ref-21","21",[521,933,934,935,938,939,944,945],{},"Some researchers went further. The ",[560,936,937],{},"hologenome theory"," proposed that the host plus its microbiome should be treated as a single unit of natural selection, with the combined genes of host and microbes, the hologenome, evolving as one. ",[545,940,549,942,555],{"className":941},[548],[551,943,927],{"href":926}," Some advocates put it strongly: we have never been individuals. ",[545,946,549,948,555],{"className":947},[548],[551,949,951],{"href":950},"#ref-22","22",[521,953,954,955,966],{},"This is where the scientific community splits. Critics point out that most animal microbes are not inherited faithfully from parent to offspring; many are picked up from the environment each generation, and the microbes have their own evolutionary interests, which may conflict with the host's. Selection acts on partnerships of very different tightness, and calling all of them one unit hides the difference between a mitochondrion and a gut bacterium that arrived last week. ",[545,956,549,958,817,962,555],{"className":957},[548],[551,959,961],{"href":960},"#ref-23","23",[551,963,965],{"href":964},"#ref-24","24"," The holobiont is a useful description of an ecological community. Whether it is always a unit of evolution is unsettled, and in many cases the evidence says it is not.",[521,968,969],{},"That disagreement is itself informative. Biological individuality is a useful concept. It is not always a clean one.",[537,971,973],{"id":972},"what-exactly-is-an-individual","What Exactly Is an Individual?",[521,975,976],{},"Try the obvious definitions and see which one survives.",[521,978,979,982],{},[560,980,981],{},"Something with one genome?"," You carry at least two kinds: the nuclear genome and the separate mitochondrial genome, which follows its own maternal line of inheritance. Your microbes bring thousands more.",[521,984,985,988,989],{},[560,986,987],{},"Something that can survive independently?"," Most of your cells cannot survive outside the body. Many symbiotic bacteria in insects have lost so many genes that they cannot live anywhere but inside their host, and the host cannot live without them. ",[545,990,549,992,555],{"className":991},[548],[551,993,995],{"href":994},"#ref-25","25",[521,997,998,1001],{},[560,999,1000],{},"Something descended from one lineage?"," Every one of your cells descends from two lineages that merged roughly two billion years ago: the host cell and the bacterium that became the mitochondrion.",[521,1003,1004,1007],{},[560,1005,1006],{},"Something enclosed by a membrane or skin?"," You exchange gases with the air every few seconds, absorb matter through the gut, and shed cells and microbes constantly. The skin is a boundary, but a busy one.",[521,1009,1010,1011,1022],{},"None of this means individuality is meaningless. Philosophers of biology treat it as a real problem precisely because the different criteria, genetic, physiological, immunological, evolutionary, usually agree and sometimes do not. ",[545,1012,549,1014,817,1018,555],{"className":1013},[548],[551,1015,1017],{"href":1016},"#ref-26","26",[551,1019,1021],{"href":1020},"#ref-27","27"," A human is meaningfully an individual organism: one body, developed from one fertilized egg, with one immune system that polices it and one nervous system that coordinates it. A cell is also a biological unit. An ecosystem can behave as an interconnected system. These descriptions are all useful, and they are not identical. Individuality exists at several overlapping levels, and which level you use depends on the question you are asking.",[537,1024,1026],{"id":1025},"back-to-earth","Back to Earth",[521,1028,1029],{},"So is Earth alive?",[521,1031,1032,1033],{},"Not necessarily. The analogy between a human and a planet has limits, and they are serious ones. Earth does not reproduce. It has no genome. It is not a member of a population of planets undergoing Darwinian selection. It does not satisfy most conventional definitions of life, and treating Gaia-as-organism as established science would be a mistake. ",[545,1034,549,1036,817,1038,555],{"className":1035},[548],[551,1037,616],{"href":615},[551,1039,640],{"href":639},[521,1041,1042],{},"But the comparison does something more interesting than answer the question. It shows how hard it is to draw clean lines around any living system. The objection \"a collection of organisms is not an organism\" is reasonable, yet it applies, with complications, to the very beings who raise it.",[521,1044,1045],{},"Life has repeatedly built larger systems out of smaller ones:",[1047,1048,1049,1053,1056,1059],"ul",{},[1050,1051,1052],"li",{},"molecules into cells;",[1050,1054,1055],{},"cells and captured bacteria into complex cells;",[1050,1057,1058],{},"complex cells into multicellular bodies;",[1050,1060,1061],{},"bodies into ecological communities.",[521,1063,1064],{},"This is a pattern in the history of life, not a direction. Evolution has no goal, and it did not set out to produce greater unity. Most lineages stayed single-celled. Mergers happened when they happened to pay, and larger systems also break apart. The pattern is real; a purpose behind it is not something the evidence shows.",[537,1066,1068],{"id":1067},"the-part-that-understands","The Part That Understands",[521,1070,1071],{},"It is tempting at this point to call humanity the brain of the Earth. The metaphor is old and flattering, and it does not hold up well. Brains coordinate the bodies they belong to. Earth's systems ran for billions of years without us, and our main effect on them so far has not been coordination.",[521,1073,1074],{},"A more modest claim survives. As far as current knowledge goes, humanity is a part of Earth's biosphere capable of understanding the biosphere.",[521,1076,1077],{},"A bacterium in your intestine does not understand the person containing it. A mitochondrion does not know that a human exists. A tree does not model the global carbon cycle.",[521,1079,1080,1081,1092],{},"Humans can. We have reconstructed past climates from ice cores and sediment. We have learned that the oxygen we breathe was first pumped into the atmosphere by cyanobacteria more than two billion years ago, and that roughly half of the planet's photosynthesis still happens in the oceans, much of it by microscopic plankton. ",[545,1082,549,1084,817,1088,555],{"className":1083},[548],[551,1085,1087],{"href":1086},"#ref-28","28",[551,1089,1091],{"href":1090},"#ref-29","29"," We measure atmospheric chemistry to parts per billion, map food webs, and model planetary feedbacks well enough to predict many consequences of our own behaviour.",[521,1094,1095],{},"That produces responsibility, and it does so without any mysticism. Humanity is not necessarily Earth's ruler, purpose, brain or chosen guardian. But we are, so far as we know, the one component of the biosphere that can understand the larger system and deliberately change its behaviour in response.",[537,1097,1099],{"id":1098},"knowing-and-doing","Knowing and Doing",[521,1101,1102],{},"And yet the knowledge has not translated into restraint.",[521,1104,1105,1106,1113,1114,1121,1122],{},"The Intergovernmental Panel on Climate Change concluded that it is unequivocal that human influence has warmed the atmosphere, ocean and land, by about 1.1 °C by the 2010s compared with the late nineteenth century. ",[545,1107,549,1109,555],{"className":1108},[548],[551,1110,1112],{"href":1111},"#ref-30","30"," The global biodiversity assessment of 2019 estimated that around a million species face extinction, many within decades, and that about three quarters of the land surface has been significantly altered by human activity. ",[545,1115,549,1117,555],{"className":1116},[548],[551,1118,1120],{"href":1119},"#ref-31","31"," The main drivers it identified are familiar: changes in land and sea use, direct exploitation of organisms, climate change, pollution and invasive species. Industrial fertilizer production now fixes nitrogen on a scale comparable to all natural land processes, and much of the excess ends up in rivers and coastal waters, where it feeds oxygen-depleted dead zones. ",[545,1123,549,1125,555],{"className":1124},[548],[551,1126,1128],{"href":1127},"#ref-32","32",[521,1130,1131,1132,1134,1135,1142],{},"The ",[560,1133,373],{}," framework tries to summarize this by estimating the ranges within which key Earth processes stayed stable during the last ten thousand years, the period in which agriculture and civilizations developed. Its 2023 update concluded that six of nine boundaries have been crossed. ",[545,1136,549,1138,555],{"className":1137},[548],[551,1139,1141],{"href":1140},"#ref-33","33"," The exact positions of those boundaries are debated, and the framework is a risk assessment, not a law of nature.",[521,1144,1145],{},"It is worth being precise about what the concern is. Nature is not a perfectly static equilibrium that humans have disturbed. Ecosystems change constantly; the planet has been far hotter and far colder than it is now, and species have always gone extinct. The issue is resilience: how much disturbance a system can absorb before it reorganizes into a different state, and whether that state remains compatible with the complex life, including the agriculture and cities, that currently depends on it. Biodiversity is part of that resilience. Systems with more interacting parts tend to have more ways to recover.",[521,1147,1148],{},"The Earth may not be an organism. But the systems it runs on are ones we are part of, and we are changing them faster than most of those systems have changed in millions of years.",[537,1150,355],{"id":1151},"the-unity-1",[521,1153,1154],{},"The title can be read several ways, and by now each has earned its place.",[521,1156,1157],{},"It is the unity of a body: tens of trillions of cells, many of them not human, and inside the human ones, descendants of ancient bacteria, working as one organism.",[521,1159,1160],{},"It is the unity of relationship: no organism on Earth lives alone, and many exist only because of partners they cannot survive without.",[521,1162,1163],{},"It is the unity of humanity with the biosphere: we do not stand outside nature looking in. We are one of its products, still running on its cycles.",[521,1165,1166,1167,1170],{},"And it is the older sense of the word, a ",[560,1168,1169],{},"unit",", something perceived as one. Every living thing we call \"one\" turns out, on close inspection, to be made of many. That does not make the one an illusion. It makes it an achievement.",[521,1172,1173],{},"We spent centuries learning to divide the world into categories: organism and environment, human and nature, self and other. Those categories are useful. But biology keeps finding connections running across their borders.",[521,1175,1176],{},"The carbon in your body was recently in the air, and before that in other bodies. The oxygen you breathe was made by other organisms. Your cells contain the descendants of free-living bacteria. Your genome contains the fossils of ancient viruses, and one of them helped build the placenta you grew inside. Your survival depends on systems that extend far beyond your skin.",[521,1178,1179],{},"You are an individual. Individuality has never meant isolation.",[521,1181,1182],{},"As far as we know, we are the first part of this planet able to see the whole of it: to trace the cycles, count the losses, and predict where they lead.",[521,1184,1185],{},"Which means we are also the first part that cannot say it did not know.",[517,1187,1189],{"id":1188},"references","References",[521,1191,1193,1197,1198,1201,1202,1204,1205],{"id":1192},"ref-1",[560,1194,1195,1196],{},"[1]"," Lovelock, J. E. (1972)."," “Gaia as seen through the atmosphere.”\n",[596,1199,1200],{},"Atmospheric Environment",", ",[560,1203,628],{},"(8), 579–580.\n",[551,1206,1207],{"href":1207,"rel":1208},"https:\u002F\u002Fdoi.org\u002F10.1016\u002F0004-6981(72)90076-5",[1209],"nofollow",[521,1211,1213,1217,1218,1201,1221,1223,1224],{"id":1212},"ref-2",[560,1214,1215,1216],{},"[2]"," Lovelock, J. E., & Margulis, L. (1974)."," “Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis.”\n",[596,1219,1220],{},"Tellus",[560,1222,1017],{},"(1–2), 2–10.\n",[551,1225,1226],{"href":1226,"rel":1227},"https:\u002F\u002Fdoi.org\u002F10.3402\u002Ftellusa.v26i1-2.9731",[1209],[521,1229,1231,1235,1236,1201,1239,1242,1243],{"id":1230},"ref-3",[560,1232,1233,1234],{},"[3]"," Feulner, G. (2012)."," “The faint young Sun problem.”\n",[596,1237,1238],{},"Reviews of Geophysics",[560,1240,1241],{},"50","(2), RG2006.\n",[551,1244,1245],{"href":1245,"rel":1246},"https:\u002F\u002Fdoi.org\u002F10.1029\u002F2011RG000375",[1209],[521,1248,1250,1254,1255,1201,1257,1259,1260],{"id":1249},"ref-4",[560,1251,1252,1253],{},"[4]"," Kirchner, J. W. (1989)."," “The Gaia hypothesis: can it be tested?”\n",[596,1256,1238],{},[560,1258,1021],{},"(2), 223–235.\n",[551,1261,1262],{"href":1262,"rel":1263},"https:\u002F\u002Fdoi.org\u002F10.1029\u002FRG027i002p00223",[1209],[521,1265,1267,1271,1272,1201,1275,1278,1279],{"id":1266},"ref-5",[560,1268,1269,1270],{},"[5]"," Doolittle, W. F. (2017)."," “Darwinizing Gaia.”\n",[596,1273,1274],{},"Journal of Theoretical Biology",[560,1276,1277],{},"434",", 11–19.\n",[551,1280,1281],{"href":1281,"rel":1282},"https:\u002F\u002Fdoi.org\u002F10.1016\u002Fj.jtbi.2017.02.015",[1209],[521,1284,1286,1290,1291,1201,1294,1297,1298],{"id":1285},"ref-6",[560,1287,1288,1289],{},"[6]"," Watson, A. J., & Lovelock, J. E. (1983)."," “Biological homeostasis of the global environment: the parable of Daisyworld.”\n",[596,1292,1293],{},"Tellus B",[560,1295,1296],{},"35","(4), 284–289.\n",[551,1299,1300],{"href":1300,"rel":1301},"https:\u002F\u002Fdoi.org\u002F10.1111\u002Fj.1600-0889.1983.tb00031.x",[1209],[521,1303,1305,1309,1310,1201,1313,1316,1317],{"id":1304},"ref-7",[560,1306,1307,1308],{},"[7]"," Kirchner, J. W. (2002)."," “The Gaia hypothesis: fact, theory, and wishful thinking.”\n",[596,1311,1312],{},"Climatic Change",[560,1314,1315],{},"52",", 391–408.\n",[551,1318,1319],{"href":1319,"rel":1320},"https:\u002F\u002Fdoi.org\u002F10.1023\u002FA:1014237331082",[1209],[521,1322,1324,1328,1329,1201,1332,1334,1335],{"id":1323},"ref-8",[560,1325,1326,1327],{},"[8]"," Sender, R., Fuchs, S., & Milo, R. (2016)."," “Revised estimates for the number of human and bacteria cells in the body.”\n",[596,1330,1331],{},"PLOS Biology",[560,1333,816],{},"(8), e1002533.\n",[551,1336,1337],{"href":1337,"rel":1338},"https:\u002F\u002Fdoi.org\u002F10.1371\u002Fjournal.pbio.1002533",[1209],[521,1340,1342,1346,1347,1201,1350,1353,1354],{"id":1341},"ref-9",[560,1343,1344,1345],{},"[9]"," Lynch, S. V., & Pedersen, O. (2016)."," “The human intestinal microbiome in health and disease.”\n",[596,1348,1349],{},"New England Journal of Medicine",[560,1351,1352],{},"375",", 2369–2379.\n",[551,1355,1356],{"href":1356,"rel":1357},"https:\u002F\u002Fdoi.org\u002F10.1056\u002FNEJMra1600266",[1209],[521,1359,1361,1365,1366,1201,1369,1372,1373],{"id":1360},"ref-10",[560,1362,1363,1364],{},"[10]"," Belkaid, Y., & Hand, T. W. (2014)."," “Role of the microbiota in immunity and inflammation.”\n",[596,1367,1368],{},"Cell",[560,1370,1371],{},"157","(1), 121–141.\n",[551,1374,1375],{"href":1375,"rel":1376},"https:\u002F\u002Fdoi.org\u002F10.1016\u002Fj.cell.2014.03.011",[1209],[521,1378,1380,1384,1385,1201,1388,1391,1392],{"id":1379},"ref-11",[560,1381,1382,1383],{},"[11]"," Kowallik, K. V., & Martin, W. F. (2021)."," “The origin of symbiogenesis: an annotated English translation of Mereschkowsky's 1910 paper on the theory of two plasma lineages.”\n",[596,1386,1387],{},"BioSystems",[560,1389,1390],{},"199",", 104281.\n",[551,1393,1394],{"href":1394,"rel":1395},"https:\u002F\u002Fdoi.org\u002F10.1016\u002Fj.biosystems.2020.104281",[1209],[521,1397,1399,1403,1404,1201,1406,1408,1409],{"id":1398},"ref-12",[560,1400,1401,1402],{},"[12]"," Sagan, L. (1967)."," “On the origin of mitosing cells.”\n",[596,1405,1274],{},[560,1407,816],{},"(3), 225–274.\n",[551,1410,1411],{"href":1411,"rel":1412},"https:\u002F\u002Fdoi.org\u002F10.1016\u002F0022-5193(67)90079-3",[1209],[521,1414,1416,1420,1421,1201,1424,1426,1427],{"id":1415},"ref-13",[560,1417,1418,1419],{},"[13]"," Nass, M. M. K., & Nass, S. (1963)."," “Intramitochondrial fibers with DNA characteristics.”\n",[596,1422,1423],{},"Journal of Cell Biology",[560,1425,894],{},"(3), 593–611.\n",[551,1428,1429],{"href":1429,"rel":1430},"https:\u002F\u002Fdoi.org\u002F10.1083\u002Fjcb.19.3.593",[1209],[521,1432,1434,1438,1439,1201,1442,1444,1445],{"id":1433},"ref-14",[560,1435,1436,1437],{},"[14]"," Gray, M. W. (2012)."," “Mitochondrial evolution.”\n",[596,1440,1441],{},"Cold Spring Harbor Perspectives in Biology",[560,1443,606],{},"(9), a011403.\n",[551,1446,1447],{"href":1447,"rel":1448},"https:\u002F\u002Fdoi.org\u002F10.1101\u002Fcshperspect.a011403",[1209],[521,1450,1452,1456,1457,1201,1460,1462,1463],{"id":1451},"ref-15",[560,1453,1454,1455],{},"[15]"," Roger, A. J., Muñoz-Gómez, S. A., & Kamikawa, R. (2017)."," “The origin and diversification of mitochondria.”\n",[596,1458,1459],{},"Current Biology",[560,1461,1021],{},"(21), R1177–R1192.\n",[551,1464,1465],{"href":1465,"rel":1466},"https:\u002F\u002Fdoi.org\u002F10.1016\u002Fj.cub.2017.09.015",[1209],[521,1468,1470,1474,1475,1201,1478,1481,1482],{"id":1469},"ref-16",[560,1471,1472,1473],{},"[16]"," Martin, W. F., Garg, S., & Zimorski, V. (2015)."," “Endosymbiotic theories for eukaryote origin.”\n",[596,1476,1477],{},"Philosophical Transactions of the Royal Society B",[560,1479,1480],{},"370",", 20140330.\n",[551,1483,1484],{"href":1484,"rel":1485},"https:\u002F\u002Fdoi.org\u002F10.1098\u002Frstb.2014.0330",[1209],[521,1487,1489,1493,1494,1201,1497,1500,1501],{"id":1488},"ref-17",[560,1490,1491,1492],{},"[17]"," International Human Genome Sequencing Consortium (2001)."," “Initial sequencing and analysis of the human genome.”\n",[596,1495,1496],{},"Nature",[560,1498,1499],{},"409",", 860–921.\n",[551,1502,1503],{"href":1503,"rel":1504},"https:\u002F\u002Fdoi.org\u002F10.1038\u002F35057062",[1209],[521,1506,1508,1512,1513,1201,1515,1518,1519],{"id":1507},"ref-18",[560,1509,1510,1511],{},"[18]"," Mi, S., et al. (2000)."," “Syncytin is a captive retroviral envelope protein involved in human placental morphogenesis.”\n",[596,1514,1496],{},[560,1516,1517],{},"403",", 785–789.\n",[551,1520,1521],{"href":1521,"rel":1522},"https:\u002F\u002Fdoi.org\u002F10.1038\u002F35001608",[1209],[521,1524,1526,1530,1531,1201,1533,1536,1537],{"id":1525},"ref-19",[560,1527,1528,1529],{},"[19]"," Lavialle, C., et al. (2013)."," “Paleovirology of ‘syncytins’, retroviral env genes exapted for a role in placentation.”\n",[596,1532,1477],{},[560,1534,1535],{},"368",", 20120507.\n",[551,1538,1539],{"href":1539,"rel":1540},"https:\u002F\u002Fdoi.org\u002F10.1098\u002Frstb.2012.0507",[1209],[521,1542,1544,1548,1549,1201,1552,1554,1555],{"id":1543},"ref-20",[560,1545,1546,1547],{},"[20]"," Zilber-Rosenberg, I., & Rosenberg, E. (2008)."," “Role of microorganisms in the evolution of animals and plants: the hologenome theory of evolution.”\n",[596,1550,1551],{},"FEMS Microbiology Reviews",[560,1553,1128],{},"(5), 723–735.\n",[551,1556,1557],{"href":1557,"rel":1558},"https:\u002F\u002Fdoi.org\u002F10.1111\u002Fj.1574-6976.2008.00123.x",[1209],[521,1560,1562,1566,1567,1201,1569,1571,1572],{"id":1561},"ref-21",[560,1563,1564,1565],{},"[21]"," Bordenstein, S. R., & Theis, K. R. (2015)."," “Host biology in light of the microbiome: ten principles of holobionts and hologenomes.”\n",[596,1568,1331],{},[560,1570,808],{},"(8), e1002226.\n",[551,1573,1574],{"href":1574,"rel":1575},"https:\u002F\u002Fdoi.org\u002F10.1371\u002Fjournal.pbio.1002226",[1209],[521,1577,1579,1583,1584,1201,1587,1590,1591],{"id":1578},"ref-22",[560,1580,1581,1582],{},"[22]"," Gilbert, S. F., Sapp, J., & Tauber, A. I. (2012)."," “A symbiotic view of life: we have never been individuals.”\n",[596,1585,1586],{},"The Quarterly Review of Biology",[560,1588,1589],{},"87","(4), 325–341.\n",[551,1592,1593],{"href":1593,"rel":1594},"https:\u002F\u002Fdoi.org\u002F10.1086\u002F668166",[1209],[521,1596,1598,1602,1603,1201,1605,1607,1608],{"id":1597},"ref-23",[560,1599,1600,1601],{},"[23]"," Moran, N. A., & Sloan, D. B. (2015)."," “The hologenome concept: helpful or hollow?”\n",[596,1604,1331],{},[560,1606,808],{},"(12), e1002311.\n",[551,1609,1610],{"href":1610,"rel":1611},"https:\u002F\u002Fdoi.org\u002F10.1371\u002Fjournal.pbio.1002311",[1209],[521,1613,1615,1619,1620,1201,1623,1625,1626],{"id":1614},"ref-24",[560,1616,1617,1618],{},"[24]"," Douglas, A. E., & Werren, J. H. (2016)."," “Holes in the hologenome: why host–microbe symbioses are not holobionts.”\n",[596,1621,1622],{},"mBio",[560,1624,640],{},"(2), e02099-15.\n",[551,1627,1628],{"href":1628,"rel":1629},"https:\u002F\u002Fdoi.org\u002F10.1128\u002FmBio.02099-15",[1209],[521,1631,1633,1637,1638,1201,1641,1643,1644],{"id":1632},"ref-25",[560,1634,1635,1636],{},"[25]"," McCutcheon, J. P., & Moran, N. A. (2012)."," “Extreme genome reduction in symbiotic bacteria.”\n",[596,1639,1640],{},"Nature Reviews Microbiology",[560,1642,691],{},", 13–26.\n",[551,1645,1646],{"href":1646,"rel":1647},"https:\u002F\u002Fdoi.org\u002F10.1038\u002Fnrmicro2670",[1209],[521,1649,1651,1655,1656,1201,1659,1661,1662],{"id":1650},"ref-26",[560,1652,1653,1654],{},"[26]"," Clarke, E. (2010)."," “The problem of biological individuality.”\n",[596,1657,1658],{},"Biological Theory",[560,1660,616],{},"(4), 312–325.\n",[551,1663,1664],{"href":1664,"rel":1665},"https:\u002F\u002Fdoi.org\u002F10.1162\u002FBIOT_a_00068",[1209],[521,1667,1669,1673,1674,1677,1678],{"id":1668},"ref-27",[560,1670,1671,1672],{},"[27]"," Wilson, R. A., & Barker, M. J."," “Biological Individuals.”\n",[596,1675,1676],{},"Stanford Encyclopedia of Philosophy",".\n",[551,1679,1680],{"href":1680,"rel":1681},"https:\u002F\u002Fplato.stanford.edu\u002Fentries\u002Fbiology-individual\u002F",[1209],[521,1683,1685,1689,1690,1201,1692,1695,1696],{"id":1684},"ref-28",[560,1686,1687,1688],{},"[28]"," Lyons, T. W., Reinhard, C. T., & Planavsky, N. J. (2014)."," “The rise of oxygen in Earth's early ocean and atmosphere.”\n",[596,1691,1496],{},[560,1693,1694],{},"506",", 307–315.\n",[551,1697,1698],{"href":1698,"rel":1699},"https:\u002F\u002Fdoi.org\u002F10.1038\u002Fnature13068",[1209],[521,1701,1703,1707,1708,1201,1711,1714,1715],{"id":1702},"ref-29",[560,1704,1705,1706],{},"[29]"," Field, C. B., Behrenfeld, M. J., Randerson, J. T., & Falkowski, P. (1998)."," “Primary production of the biosphere: integrating terrestrial and oceanic components.”\n",[596,1709,1710],{},"Science",[560,1712,1713],{},"281","(5374), 237–240.\n",[551,1716,1717],{"href":1717,"rel":1718},"https:\u002F\u002Fdoi.org\u002F10.1126\u002Fscience.281.5374.237",[1209],[521,1720,1722,1726,1727,1730,1731,1734,1735],{"id":1721},"ref-30",[560,1723,1724,1725],{},"[30]"," IPCC (2021)."," “Summary for Policymakers.” In ",[596,1728,1729],{},"Climate Change 2021: The Physical Science Basis",". Contribution of Working Group I to the Sixth Assessment Report.\n",[596,1732,1733],{},"Cambridge University Press",", 3–32.\n",[551,1736,1737],{"href":1737,"rel":1738},"https:\u002F\u002Fdoi.org\u002F10.1017\u002F9781009157896.001",[1209],[521,1740,1742,1746,1747,1750,1751],{"id":1741},"ref-31",[560,1743,1744,1745],{},"[31]"," IPBES (2019)."," “Summary for policymakers of the global assessment report on biodiversity and ecosystem services.”\n",[596,1748,1749],{},"IPBES Secretariat",", Bonn.\n",[551,1752,1753],{"href":1753,"rel":1754},"https:\u002F\u002Fdoi.org\u002F10.5281\u002Fzenodo.3553579",[1209],[521,1756,1758,1762,1763,1201,1765,1767,1768],{"id":1757},"ref-32",[560,1759,1760,1761],{},"[32]"," Fowler, D., et al. (2013)."," “The global nitrogen cycle in the twenty-first century.”\n",[596,1764,1477],{},[560,1766,1535],{},", 20130164.\n",[551,1769,1770],{"href":1770,"rel":1771},"https:\u002F\u002Fdoi.org\u002F10.1098\u002Frstb.2013.0164",[1209],[521,1773,1775,1779,1780,1201,1783,1785,1786],{"id":1774},"ref-33",[560,1776,1777,1778],{},"[33]"," Richardson, K., et al. (2023)."," “Earth beyond six of nine planetary boundaries.”\n",[596,1781,1782],{},"Science Advances",[560,1784,683],{},"(37), eadh2458.\n",[551,1787,1788],{"href":1788,"rel":1789},"https:\u002F\u002Fdoi.org\u002F10.1126\u002Fsciadv.adh2458",[1209],{"title":1791,"searchDepth":92,"depth":92,"links":1792},"",[1793,1794,1795,1796,1797,1798,1799,1800,1801,1802,1803],{"id":539,"depth":92,"text":540},{"id":590,"depth":92,"text":591},{"id":658,"depth":92,"text":659},{"id":706,"depth":92,"text":707},{"id":842,"depth":92,"text":843},{"id":913,"depth":92,"text":914},{"id":972,"depth":92,"text":973},{"id":1025,"depth":92,"text":1026},{"id":1067,"depth":92,"text":1068},{"id":1098,"depth":92,"text":1099},{"id":1151,"depth":92,"text":355},"md",[358,359,360,361,362,363,364,365,366,367,368,369,370,371,372,373,374,203],{},true,{"title":355,"description":356},"evidence\u002Fthe-unity","iS4i3pKA5O36Lk5ucXIDcT3_jgpm3n8rSWDhuHTsDEo",1790022709877]