a rt i s t s ’ a rt i c l e The Living Cosmos: A Fabric That Binds Art and Science
Chris Impey a b s tr a c t and Heather Green The authors, an astronomer and an artist, have collaborated on a series of seven mixed- media constructions and prose pieces that follow the flow and themes of Impey’s book on astrobiology, The Living The Project In the first art piece, from the Cosmos. The book summarizes viewer’s vantage point on a shore, recent research on astrobiology, After authors Chris Impey and Heather Green worked to- from the origin of life on Earth gether on a series of posters in which artist Green layered Ernst night sky shades imperceptibly into and its environmental range on Haeckel’s illustrations of diatoms with imagery of computer noctilucent sea (Fig. 1). Familiar this planet to the search for life circuitry and dark matter, Chris Impey approached Green with surfaces—a glassy sea, the hemi- in the solar system and beyond. spheric vault of the sky—seem The artist’s work encapsulates the idea of creating seven pieces that would capture the es- these ideas with its use of mate- sence of each of the chapters in his popular book on astrobiol- proximate but each contains vast rial objects, textures, images ogy, The Living Cosmos [1]. depths and each might host un- and metaphors that mirror Over several meetings in Green’s studio, the two discussed known and unseen creatures. The the elements of the scientific approach to astrobiology. how the content of each chapter could be expressed visually. shore represents a boundary be- Green created conceptual sketches of materials and themes tween knowledge and ignorance, that could serve as metaphors for larger ideas in the book dreams and reality. The macrocos- (and that served as the basis for the shadow box designs pre- mic and the microcosmic face each sented below), and Impey followed with prosaic writing that other as mirrors. complemented these sketches, as can be seen in the follow- ing sections of this paper, which draw from those passages. As Fig. 1. Heather Green, The Unfinished Revolution, oil on panel, ideas developed, they became less literal, and in the process etched clock crystals, etched copper, steel and wood, 14 × 19 × 4 in, 2007. (© Heather Green) of their distillation a kind of logic evolved. The conversations resulted in an inspiring exchange of knowledge, and the ico- nography for the project emerged. The pieces are tethered to the sequential development of the book, but they can be observed in any order; the motifs build on one another and are interconnected, like the web of life [2]. The choice of working with shadow boxes was intentional— it allowed Green to work with found objects and 2- and 3D materials that were relevant to the work and to reference mu- seums and scientific specimens (especially the tradition of the Wunderkammer [3]) and the constructions of Joseph Cornell, who created several boxes with astronomical themes [4].
The Unfinished Revolution The first chapter of The Living Cosmos sets the stage for the field of astrobiology. The history of astronomy has seen us continually displaced from our presumed centrality in the universe [5]. We inhabit a hospitable but not atypical rocky planet orbiting a moderate-weight, middle-aged star near the periphery of a normal spiral galaxy, one of billions in the ex- panding universe. Astrobiology is an interdisciplinary effort to discover if life on Earth is special and unique or if we live in a biological universe.
Chris Impey (scientist, educator), Steward Observatory, University of Arizona, Tucson, AZ 85721, U.S.A. E-mail:
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Downloaded from http://direct.mit.edu/leon/article-pdf/43/5/435/1579669/leon_a_00035.pdf by guest on 30 September 2021 At the bottom of the image, an in- we are, formed from a universal bio- Italian of Galileo as he communicated complete periodic table symbolizes the chemistry [7]. science to the general public, Newton’s scientific process. We look for patterns The concave clock crystals in the cen- English as he explained the enigma of in nature, in a process that began when ter of the image draw us in and place us gravity and the German of Einstein and the first civilizations began to track the at the center of the scene. They are pri- his theories of relativity. cycles of time in the sky. Scientists work meval forms, perfect and Pythagorean, The forms are timeless yet modern. A with fragments of knowledge to infer numbering five to represent the Platonic flat horizon conveys infinite extent and the whole: an extinct creature from solids, the moving objects in the night posits Earth as both the beginning and a few scattered bones, the history of sky or the Greek elements. The curved end of the universe, but the clock crystals, animals from the 1% of their bones that surface might be a cornea or the lens of by breaking the plane, refer to Einstein’s are fossilized [6] and the commonality of an early telescope. The nested spheres curved universe and his coupling of life from the overlap of scraps of DNA. allude to mathematical harmony, to space and time [8]. Comforting bound- The power of science lies in its projec- Dante’s cosmology and to the onion aries melt away. The straight edge of sea tive capability. Newton used the orbits skin of knowledge. They move inward is the limb of a gently curving planet, of a few planets to infer the motions of in time, with exterior shells closer to the with no up or down. There is no shel- galaxies that would not be discovered origin, like the growing bubbles of light tering sky, and the air shades smoothly until centuries after his death. The pe- that surround every star. They are etched into the perfect vacuum of deep space. riodic table is universal. Stars are made in languages that bespeak the history of Greek philosophers flinched at the idea of the same ingredients as the Sun, and science: Greek from Plato’s Academy, of a universe with no edge, or an edge yet if planets around some of them host the Latin of Copernicus in his book that nothing beyond the edge. The universe life, it will be made of the same stuff as shocked and displaced the world, the might be boundless, limited by time and not space, our view defined by the dis- Fig. 2. Heather Green, Life’s Origins, oil on panel, etched glass, specimen jar with sand, ash, tance that light has traveled since the big crystal, sculpted book page strata, wood, 14 × 19 × 4 in, 2007. (© Heather Green) bang. All that we see is only a tiny fraction of the physical universe [9].
Life’s Origins The Living Cosmos continues its story by going back to 4 billion years ago, a time since which all traces of biology have been churned into the restless Earth, when the motor of life first turned over. Chemical shards slowly assembled by trial and error into chunks of RNA and then into the rudiments of a working cell [10]. From a simple beginning, Darwin’s “end- less forms most beautiful and wonderful” have evolved to carpet the planet. In the second work, an old man and his grandson regard a night scene (Fig. 2). Their starry silhouettes are a remin- der that we are all stardust, our genera- tions of atoms cycled through cosmic cauldrons. The Moon was our first guide to tracking deep time, the word itself coming from a Greek root meaning “to measure.” Its cratered surface is a mir- ror of the Earth’s violent history and the random impacts that disrupt evolu- tion [11]. Yet it also stabilizes the Earth’s orbit, making the planet more convivial to biology. More recently, we have min- iaturized our timekeeping, using vibra- tions of atoms, the precise shimmering of light waves and the radioactive decay of massive atoms—the clocks in the rock. Below us, the book of life is laid out like crumpled pages in the strata beneath our feet. The story of evolution on Earth can be parsed from the slowly mutating base pairs of DNA, but this information de- grades with time, like paper turning to dust [12]. So little remains after eons of geological activity that reanimating a di- nosaur from its blood sucked by an insect
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Downloaded from http://direct.mit.edu/leon/article-pdf/43/5/435/1579669/leon_a_00035.pdf by guest on 30 September 2021 and then trapped in amber would be like trying to reconstruct a library from a few scattered book pages. We are the universe, and the universe is us. Water and carbon are leitmotifs in this story and in these artworks. Water is the placental fluid, a universal solvent, so the fact that all plants and animals are largely made of salty water is a reminder of our origins. Carbon is the universal building block. Its delicate forms are etched on the glass. The specimen jar is an allusion to Miller and Urey’s famous “life-in-a-bottle” experiments [13], which re-created the first steps from simple molecules to amino acids. Within the jar, carbon is mixed with silica in a layer of mud, in an allusion to the periodic molecular structure of clay sheets acting as templates for the first replicator—the story of the Golem. The ash connotes combustion, the energy released in life and death. Carbon cycles in and out of the biosphere every million years or so and has done so thousands of times since life began. Crystals in the piece connote the capture of geological history in deli- cate forms. Some, like diamonds, are the result of enormous pressure. Others, like zircons, can be as old as the Earth itself. All speak to a cosmic history that forged their elements in the cores of stars [14]. With vivid imagining, we can see heaven in a grain of sand.
Extreme Life Next up in The Living Cosmos is a con- sideration of extremophile life forms. We imagine ourselves as Earth’s rugged generalists, but in truth, we are frail. We share the planet with microbes that would be at home in boiling water or Fig. 3. Heather Green, Extreme Life, oil on panel, etched glass, steel, wood, 14 × 19 × 4 in, deep rock or pure salt or battery acid. 2007. (© Heather Green) Their diverse forms are represented in spectral color. Life has radiated into ev- an organism from scratch [16]. Humans more microbial DNA contained in the ery environmental niche [15]. Robust is may be heading toward a post-biological very poorly understood microbes in a biology’s middle name—it is our fragility future, when we pass through the mem- teaspoon of seawater than in the human that is unusual. brane of progress to a point where tech- genome [19]. These extremophile mi- In the corresponding art piece, the nology usurps the organism [17]. There crobes thrive in places where we cannot core thread is DNA (Fig. 3). This delicate is tension between the reductionist view live: in pore spaces deep within a rock, molecular ladder both codes and trans- of life fostered by genetics and our sus- bathed in acidic runoff from an aban- mits information, and whatever experi- picion that there is something special doned mine, rapidly repairing their mentation might have taken place on the about the spark of life. radiation-damaged DNA in the shadow primeval Earth, organisms using DNA Humans are temporary visitors in an of a nuclear reactor. We can visualize tar- superseded and consumed all others. A overwhelmingly microbial world. The digrades, or water bears, no bigger than base pair is like a letter, a gene is like a modern tree of life based on DNA places the head of a pin, albino fish foraging sentence, the genome is like an encyclo- us and all other animals as a peripheral near an undersea volcano and sea worms pedia and all aspects of the organism are twig [18]. Genetic diversity and complex- projecting in undulating waves of pink coded in genetic material and its com- ity at the microscopic level are amazing. from a sheet of methane ice on the ocean plex interactions with the environment. We are not quite as special as we think— floor. The concept of life as information leads we share half our DNA with yeast and we All this occurs on just one modest-sized to the possibility of artificial life: life with- have no more genes than some much- planet: Earth. Life beyond Earth might out carbon and water. Biologists are tin- simpler organisms. There are far more not only be stranger than we imagine, kering with molecular Legos in the lab, microbes in one person’s gut than there it might be stranger than we can imag- trying to improve on nature and build are people on the planet, and there is ine. Rumpled bed sheets in Fig. 3 sug-
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Downloaded from http://direct.mit.edu/leon/article-pdf/43/5/435/1579669/leon_a_00035.pdf by guest on 30 September 2021 destroy continents and ecosystems [22]. Dying stars can be seen in daylight; they are also like Vishnu, creators and destroyers of life, providing the heavy elements needed for biology, but irra- diating nearby life until its defenses are weakened. Celestial ephemera speak to a con- tingency in evolution. Fitness is pyrrhic when nature rolls the dice and the strong die. On the other hand, life finds com- mon solutions to the problem of sur- vival on a fickle planet; eyes and wings and feathers have arisen multiple times in dispersed branches of the tree of life [23]. Organisms do not always become large and complex; the dominion of an- aerobic bacteria is without parallel, yet millions could fit on the dot at the end of this sentence. Below the glass, a scene in etched copper shows the burgeoning life in Earth’s Cambrian oceans, a remark- able change after 3 billion years of being invisibly small.
Living in the Solar System The only place we have scrutinized for life is our back yard: the solar system. The Living Cosmos considers nearby potential sites for biology. Straddling the Earth in space, our near neighbors subvert stereo- types of history and culture and feature strongly in the relevant art piece (Fig. 4). Mars has a geologically dead surface vis- ible through a thin veil of atmosphere. Its permafrost may hold traces of ancient life [24]. In stark contrast, Venus, named for the Goddess of Love, is a toxic night- mare of volcanoes, a bone-crushing, le- thal atmosphere of carbon dioxide and Fig. 4. Heather Green, Living in the Solar System, oil on panel, steel, antique light bulbs, sulfuric acid, with a surface temperature carved topo map, wood, 14 × 19 × 4 in, 2007.(© Heather Green) that would melt lead. Mars of the imagination. Embedded gest landscapes and the contours of the The art piece Shaping Evolution (Color in myth and legend, Mars is cast as the imagination and dreams. Our biology Plate B No. 1) uses thick layers of etched Jungian archetype of our darker side. may be only one solution for life. It is a glass to convey the growth in complex- When Percival Lowell saw the surface pleasant valley, but not the only dwelling ity of life on Earth. The terrestrial stage markings, he conjured up a dying race place and not necessarily the best of all forms from a swirling cloud of gas and bringing polar water to the barren equa- possible worlds. Biology elsewhere may dust. Tiny particles collide and stick; torial region. Young Orson Welles caused be wildly or unrecognizably different. smoke becomes dust bunnies and rocky a mini-exodus with a reality-style radio snowflakes. In a crescendo of accre- broadcast announcing that the Martians Shaping Evolution tion, molehills grow into mountains and were arriving with ill intent. In comics The Living Cosmos turns next to the his- then planets [21]. The primeval Earth and science fiction and our imaginations, tory of life, seen through a glass darkly. was an antechamber to Hell, with wide- Mars is a timeless, windswept place of The layers of the Earth hold traces of spread volcanism and oceans barely con- lost dreams [25]. On the real Mars, two 500 million years of evolution, of hard densed from steam. Comets and meteors intrepid rovers little bigger than Tonka body parts turned to stone and crystal as slammed into the surface. They set the toys roam across the rugged terrain [26]. if by a magician’s spell [20]. A drill or stage for biology by carrying water from A small flotilla of spacecraft heads there shovel acts as a time machine, although a the outer solar system and phosphorus to map the surface and test the soil for tumult of geological change and erosion to make the energy molecule ATP. They biology. The most muscular projection of inverts some strata and eradicates others. also bring mayhem; from time to time humans off-Earth has us using technol- In every conceivable niche, the Earth is the Earth sweeps through a hail of death ogy to green the red planet, to create a vibrantly, opulently alive. from comet debris, and the big impacts bolthole in case we soil our world beyond
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Downloaded from http://direct.mit.edu/leon/article-pdf/43/5/435/1579669/leon_a_00035.pdf by guest on 30 September 2021 repair, or a new world for visionaries and As we venture out gingerly into space, it out carbon. They will be satisfying a pri- explorers. will be on multi-generational arks, with mal human itch, as when our ancestors Venus of the imagination. It regards us passengers willing to take a one-way trip roamed from Siberia to Patagonia in a balefully like a small milky eye, the bright- to an unknown future. Our destiny in scant few thousand years. est object of the dusk and dawn sky, the space is fueled by technology and the crux of Mayan cosmology. In popular cul- exponential rise in computation. Space ture it spawns lurid fantasies of fabulous probes are just extensions of ourselves, Are We Alone? space women—the pulp fiction would projections of our eyes and ears. We are We contemplate a universe of which raise the pulse of any teenager. In the art exploring our backyard for now, but we are an indescribably small part (Fig. piece the strata of cutout comic books these robotic probes will some day travel 6). Within our heads we hold the sci- represent the contours of the imagina- on the fleet feet of anti-matter [30]. They entific basis for the creation and evo- tion. In reality Venus is a bad dream from will build replicas of themselves by min- lution of a universe that contains 10 an inner circle of Hell. Three billion years ing asteroids and fanning out across the thousand billion billion stars, and a ago Mars, Venus and the Earth may have galaxy. It will almost be as if we are there, statistical near-certainty of companion- been equally habitable, but now Venus because they will be our creations, our ship. However, science itself is mute stands as a warning of what happens if we children. to meaning. let global warming run amok [27]. The When the first human adventurers The Living Cosmos ends with the search old light bulbs in Fig. 4 are metaphors descend on a remote terrestrial planet, for extraterrestrial intelligence, which as- for growth and energy, containment and nobody knows what they will find: a sumes that the events on Earth that led eventual death. From within, the heat of shiny metallic sea (as in the art piece), to the development of large brains and radioactivity powers a planet. A slender a landscape of pure crystal or life with- technology are not unique. The physicist sheath of atmosphere protects us from the harshness of space debris and cosmic rays. Far from a star, habitable zones may Fig. 5. Heather Green, Distant Worlds, oil on panel, etched glass, computer motherboard, steel, wood, 14 × 19 × 4 in,2007. (© Heather Green) be razor-thin. Perhaps our pale blue dot is the Goldilocks planet.
Distant Worlds The dreamers got there first. In their mind’s eyes, the galaxy was littered with worlds, some living and some dead. Only gravity and crude technology kept us earthbound. Astronomers have finally caught up with the vision. The Living Cosmos describes the success of their quixotic quest after decades of failed attempts. Since 1995, they have discov- ered over 350 planets beyond the solar system [28]. Earth is a spaceship, as Fig. 5 conveys. Even while standing still, we trace a cork- screw motion through space as we spin and orbit the Sun. On an even more gi- gantic scale, we conduct a circuit of the Milky Way every quarter-billion years, dipping in and out of the star fields and nebulae of the disk. The first astronauts to orbit the Earth experienced the shock of the new: a small watery planet set against a void. Distant twins of Earth pass unnoticed like fireflies next to the flood- lights of their parent stars. Astronomers found exoplanets by stealth, detecting the periodic stretching and squashing of the light waves from the star as the planet tugs it around like an unruly dog on a leash. We have found clones of Jupiter and clones of Neptune and Uranus, and a harvest of clones of Earth is only a de- cade away [29]. Earth is an ark. We know enough about the harshness of space to suspect that the bounty of our biosphere may be special.
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Downloaded from http://direct.mit.edu/leon/article-pdf/43/5/435/1579669/leon_a_00035.pdf by guest on 30 September 2021 Enrico Fermi once asked the pointed we touch the water and we look to the We are divided against ourselves: a question, “Where are they?” With one sky. Rooted in our water world, we are young race full of poise and promise, hundred million habitable worlds in our made of water and think it is the best but also tainted by aggression. We want galaxy, it seemed implausible that alien basis for biology. Water is one of the to know the alien, but through windows life forms should not have matched and most abundant molecules in the uni- on the universe perhaps we are looking eclipsed our capabilities [31]. With up verse, and watery planets are expected for and seeing ourselves. to a 5-billion-year head start, they could to be common in remote solar systems. be to us as we are to the microbes on this We touch the sky and look at the water. planet. We are lonely and search for com- Below its surface, cephalopods and ceta- Materials and Metaphors panionship with messages tossed into the ceans provide nearby examples of alien The materials in the art pieces are uni- ocean of night. We also communicate in- intelligences decoupled from technology versal. The sinuous molecules that bind advertently with a bubble of radio and TV [33]; however rich their inner lives, they pigments in oil paint are like those that transmissions that has by now enveloped will not point telescopes at the sky and beaded up in Earth’s primeval oceans to planets around a thousand stars [32]. puzzle about their place in the universe. form the first cell. Glass is a translucent Understanding might be elusive in dia- Our anthropocentric tendencies mean form of sand and is representative of the log with aliens of unknown function and that we may not be able to recognize mineral content of the Earth’s mantle form. When we look into the eyes of an an alien intelligence, or the distinction and Earth-like planets elsewhere. Metal ape, it is sobering to know that we cannot between natural objects and artifacts. is a relic of supernovae, the fiery stel- even communicate with a creature that Their powers may be godlike and may lar cataclysms that also enable biology shares 99% of our DNA. include the ability to simulate creatures by forging and ejecting life’s elements. Windows are also mirrors. In Fig. 6, like us. Wood panels and paper are among the means by which formerly living things are brought into our service, making Fig. 6. Heather Green, Are We Alone? oil on panel, etched glass, wood, 14 × 19 × 4 in, 2007. art an indirect homage to carbon and (© Heather Green) biology. The themes in the artworks are univer- sal. Living organisms are poised near the logarithmic center of a range of scales from the nucleus of an atom to the gran- deur of a spiral galaxy. We still struggle to understand the universe of which we are a microscopic part, amazed that comprehension is possible at all. We are surrounded by horizons and boundar- ies, yet some are as illusory as the limits we place on our imaginations. Protean forms of nature—from stars and plan- ets, to crystals, fossils and the double helix of DNA—are the grist of scien- tific explanation and of dreams. They exist in the physical world and also as metaphors. It comes down to trust. The artist trusts that his or her vision and craft can be rooted in a particular sensibility and ex- perience yet articulate a vision that reso- nates broadly and tells a universal truth. As Hermann Hesse wrote, “The highest art sets down its creations and trusts in their magic, without fear of being misun- derstood” [34]. The scientist trusts that the limited compass of perception will not prevent the discovery of a guiding principle of nature. Science and art are both quintessentially optimistic human activities. Trust also defines the space be- tween the artist and the scientist. Coming from separate traditions, they can find middle ground between the palette and the spectrum, between life as we know it and life as we imagine it and between the evanescent mutability of artistic in- vention and the obdurate exactness of data.
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Downloaded from http://direct.mit.edu/leon/article-pdf/43/5/435/1579669/leon_a_00035.pdf by guest on 30 September 2021 Astrobiology: The 3. Susan Pierce, On Collecting: An Investigation into 26. S. Squyres, Roving Mars: Spirit, Opportunity, and Collecting in the European Tradition (London and New the Exploration of the Red Planet (New York: Hyperion, Scientist’s Perspective York: Routledge, 1995) pp. 109–121. 2005). (Chris Impey) 4. K. Hoving, Joseph Cornell and Astronomy: A Case for 27. D. Grinspoon, Venus Revealed: A New Look Below In a universe ripe for biology, it is natural the Star (Princeton, NJ: Princeton University Press, the Clouds of our Mysterious Twin Planet (New York: to speculate on the existence and nature 2008). The final work had its debut in fall 2007 in the Basic Books, 1998). lobby of the University of Arizona Science Library, of biology elsewhere. I was drawn to this in spring of 2008 it was displayed at the University of 28. F. Casoli and T. Encrenaz, The New Worlds: Extra- collaboration by the insight and sensitiv- Arizona’s Flandrau Science Center, and in the sum- solar Planets (New York: Springer, 2007). mer of 2008 it moved to the Bio5 Institute’s Thomas 29. J. Lissauer, “How Common Are Habitable Plan- ity the artist brought to imagining life in W. Keating Research building, where it has been in- ets?” Nature, 402, pp. C11–C14 (1999). the universe. Induction can only go so far cluded in the permanent collection. 30. P. Gilster, Centauri Dreams: Imagining and Planning in imagining how strange life might be 5. T. Ferris, Coming of Age in the Milky Way (New York: Interstellar Exploration (Berlin: Springer, 2004). on distant worlds. Astrobiology creates a Morrow, 1988). 31. S. Webb, If the Universe Is Teeming with Aliens deep resonance with a fundamental as- 6. M.J. Benton and D.A.T. Harper, Introduction to . . . Where Is Everybody? Fifty Solutions to Fermi’s Paradox pect of the human condition: the loneli- Paleobiology and the Fossil Record (Chichester: Wiley- and the Problem of Extraterrestrial Intelligence (New York: Blackwell, 2009). ness we might feel if we learned we were Springer, 2002). adrift in a vast and lifeless universe. 7. N. Pace, “The Universal Nature of Biochemistry,” 32. S. Shostak, Confessions of an Alien Hunter: A Scien- Proceedings of the National Academy of Sciences, 98, No. tist’s Search for Extraterrestrial Intelligence (Washington, 8, pp. 805–808 (2001). DC: National Geographic, 2009). 8. A. Lightman, Einstein’s Dreams (New York: Random Astrobiology: The 33. J. Catalani, “Cephalopod Intelligence,” American House, 1993). Artist’s Perspective Paleontologist, 19, No. 3, pp. 35–39 (2008). 9. C.H. Lineweaver and T.M. Davis, “Misconceptions (Heather Green) 34. H. Hesse, Reflections (New York: Farrar, Strauss, about the Big Bang,” Scientific American, March, pp. and Giroux, 1974). The recurring motif of the horizon dis- 36–45 (2005). 35. R. Solnit, Storming the Gates of Paradise: Landscapes secting a cluster of stars above from the 10. R. Hazen, Genesis: The Scientific Quest for Life’s Ori- for Politics (Berkeley, CA: University of California gins (Washington, DC: Joseph Henry Press, 2005). bioluminescence in a night sea below, Press, 2008). prevalent in the artwork, creates a per- 11. P. Plait, Death from the Skies! These Are the Ways the fect allegory for the ideas Chris Impey World Will End (New York, Penguin: 2008). Resources examines in The Living Cosmos. The ex- 12. C. Woese, “Interpreting the Universal Phyloge- panse beyond Earth contrasts with and netic Tree,” Proceedings of the National Academy of Sci-
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