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SETI in vivo: testing the we-are-them hypothesis

Published online by Cambridge University Press:  10 July 2017

Maxim A. Makukov  and
Vladimir I. shCherbak
Maxim A. Makukov*
Affiliation:
Fesenkov Astrophysical Institute, Almaty, Republic of Kazakhstan
Vladimir I. shCherbak
Affiliation:
Al-Farabi Kazakh National University, Almaty, Republic of Kazakhstan
*
e-mail: [email protected]
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Abstract

After it was proposed that life on Earth might descend from seeding by an earlier extraterrestrial civilization motivated to secure and spread life, some authors noted that this alternative offers a testable implication: microbial seeds could be intentionally supplied with a durable signature that might be found in extant organisms. In particular, it was suggested that the optimal location for such an artefact is the genetic code, as the least evolving part of cells. However, as the mainstream view goes, this scenario is too speculative and cannot be meaningfully tested because encoding/decoding a signature within the genetic code is something ill-defined, so any retrieval attempt is doomed to guesswork. Here we refresh the seeded-Earth hypothesis in light of recent observations, and discuss the motivation for inserting a signature. We then show that ‘biological SETI’ involves even weaker assumptions than traditional SETI and admits a well-defined methodological framework. After assessing the possibility in terms of molecular and evolutionary biology, we formalize the approach and, adopting the standard guideline of SETI that encoding/decoding should follow from first principles and be convention-free, develop a universal retrieval strategy. Applied to the canonical genetic code, it reveals a non-trivial precision structure of interlocked logical and numerical attributes of systematic character (previously we found these heuristically). To assess this result in view of the initial assumption, we perform statistical, comparison, interdependence and semiotic analyses. Statistical analysis reveals no causal connection of the result to evolutionary models of the genetic code, interdependence analysis precludes overinterpretation, and comparison analysis shows that known variations of the code lack any precision-logic structures, in agreement with these variations being post-LUCA (i.e. post-seeding) evolutionary deviations from the canonical code. Finally, semiotic analysis shows that not only the found attributes are consistent with the initial assumption, but that they make perfect sense from SETI perspective, as they ultimately maintain some of the most universal codes of culture.

Keywords

genetic codeplanetary seedingsemioticsSETI
Type
Research Article
Information
International Journal of Astrobiology , Volume 17 , Issue 2 , April 2018 , pp. 127 - 146
Copyright
Copyright © Cambridge University Press 2017 

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References

Ahituv, N., Zhu, Y., Visel, A., Holt, A., Afzal, V., Pennacchio, L.A. & Rubin, E.M. (2007). Deletion of ultraconserved elements yields viable mice. PLoS Biol. 5, e234.Google Scholar
Amirnovin, R. (1997). An analysis of the metabolic theory of the origin of the genetic code. J. Mol. Evol. 44, 473–476.Google Scholar
Anglada-Escude, G. et al. (2014). Two planets around Kapteyn's star: a cold and a temperate super-Earth orbiting the nearest halo red dwarf. Mon. Not. R. Astron. Soc. Let. 443, L89–L93.CrossRefGoogle Scholar
Bains, W. & Schulze-Makuch, D. (2016). The cosmic zoo: the (near) inevitability of the evolution of complex, macroscopic life. Life 6, 25.CrossRefGoogle ScholarPubMed
Baranov, P.V., Atkins, J.F. & Yordanova, M.M. (2015). Augmented genetic decoding: global, local and temporal alterations of decoding processes and codon meaning. Nat. Rev. Genet. 16, 517–529.Google Scholar
Bell, E.A., Boehnke, P., Harrison, T.M. & Mao, W.L. (2015). Potentially biogenic carbon preserved in a 4.1 billion-year-old zircon. Proc. Natl. Acad. Sci. USA 112, 14518–14521.CrossRefGoogle Scholar
Brar, G.A. (2016). Beyond the triplet code: context cues transform translation. Cell 167, 1681–1692.CrossRefGoogle ScholarPubMed
Campante, T.L. et al. (2015). An ancient extrasolar system with five sub-Earth-size planets. Astrophys. J. 799, 170.Google Scholar
Chin, J.W. (2014). Expanding and reprogramming the genetic code of cells and animals. Annu. Rev. Biochem. 83, 379–408.Google Scholar
Chrisomalis, S. (2010). Numerical Notation: A Comparative History. Cambridge University Press, Cambridge.Google Scholar
Ćirković, M.M. (2014). Evolutionary contingency and SETI revisited. Biol. Philos. 29, 539–557.CrossRefGoogle Scholar
Conway Morris, S. (2003a). Life's Solution: Inevitable Humans in a Lonely Universe. Cambridge University Press, Cambridge.CrossRefGoogle Scholar
Conway Morris, S. (2003b). The navigation of biological hyperspace. Int. J. Astrobiol. 2, 149–152.CrossRefGoogle Scholar
Conway Morris, S. (2011). Predicting what extra-terrestrials will be like: and preparing for the worst. Phil. Trans. R. Soc. A 369, 555–571.CrossRefGoogle Scholar
Crick, F.H.C. (1981). Life Itself: Its Origin and Nature. Simon & Schuster, New York.Google Scholar
Crick, F.H.C. & Orgel, L.E. (1973). Directed panspermia. Icarus 19, 341–346.CrossRefGoogle Scholar
Danckwerts, H.J. & Neubert, D. (1975). Symmetries of genetic code-doublets. J. Mol. Evol. 5, 327–332.CrossRefGoogle ScholarPubMed
Dantzig, T. (1954). Number: The Language of Science, 4th edn. Simon & Schuster, New York.Google Scholar
Davies, P.C.W. (2012). Footprints of alien technology. Acta Astronaut. 73, 250–257.Google Scholar
Davis, J. (1996). Microvenus. Art. J. 55, 70–74.Google Scholar
Dawkins, R. (2004). The Ancestor's Tale: A Pilgrimage to the Dawn of Life. Houghton Mifflin Harcourt, Boston.Google Scholar
de Grijs, R. (2010). A revolution in star cluster research: setting the scene. Phil. Trans. R. Soc. A 368, 693–711.Google Scholar
Deacon, T.W. (1997). The Symbolic Species: The Co-evolution of Language and the Brain. W.W. Norton & Co, New York.Google Scholar
Di Giulio, M. (2004). The coevolution theory of the origin of the genetic code. Phys. Life Rev. 1, 128–137.Google Scholar
Doolittle, W.F. (2000). The nature of the universal ancestor and the evolution of the proteome. Curr. Opin. Struct. Biol. 10, 355–358.CrossRefGoogle ScholarPubMed
Forterre, P. & Philippe, H. (1999). Where is the root of the universal tree of life? BioEssays 21, 871–879.Google Scholar
Fournier, G.P. & Gogarten, J.P. (2007). Signature of a primitive genetic code in ancient protein lineages. J. Mol. Evol. 65, 425–436.CrossRefGoogle ScholarPubMed
Freeland, S.J. & Hurst, L.D. (1998). The genetic code is one in a million. J. Mol. Evol. 47, 238–248.Google Scholar
Freitas, R.A. (1983). The search for extraterrestrial artifacts (SETA). J. Br. Interplanet. Soc. 36, 501–506.Google Scholar
Gazalé, M. (2000). Number: From Ahmes to Cantor. Princeton University Press, Princeton.Google Scholar
Gibbs, W.W. (2001). Art as a form of life. Sci. Am. 284, 37–39.Google Scholar
Gibson, D.G. et al. (2010). Creation of a bacterial cell controlled by a chemically synthesized genome. Science 329, 52–56.Google Scholar
Giegé, R. (2008). Toward a more complete view of tRNA biology. Nat. Struct. Mol. Biol. 15, 1007–1014.Google Scholar
Glansdorff, N., Xu, Y. & Labedan, B. (2008). The last universal common ancestor: emergence, constitution and genetic legacy of an elusive forerunner. Biol. Dir. 3, 29.CrossRefGoogle ScholarPubMed
Gould, S.J. (1985). The Flamingo's Smile: Reflections in Natural History. Norton & Co, New York.Google Scholar
Gould, S.J. (1989). Wonderful life: The Burgess Shale and the Nature of History. Norton & Co, New York.Google Scholar
Gros, C. (2016). Developing ecospheres on transiently habitable planets: the genesis project. Astrophys. Space Sci. 361, 324.Google Scholar
Guo, M. & Schimmel, P. (2013). Essential nontranslational functions of tRNA synthetases. Nat. Chem. Biol. 9, 145–153.CrossRefGoogle ScholarPubMed
Haldane, J.B.S. (1954). The origins of life. New Biol. 16, 12–27.Google Scholar
Hasegawa, M. & Miyata, T. (1980). On the antisymmetry of the amino acid code table. Orig. Life 10, 265–270.CrossRefGoogle ScholarPubMed
Hayes, B. (1998). The invention of the genetic code. Am. Sci. 86, 8–14.Google Scholar
Hoch, J.A. & Losick, R. (1997). Panspermia, spores and the Bacillus subtilis genome. Nature 390, 237–238.Google Scholar
Hoffman, D.C., Anderson, R.C., DuBois, M.L. & Prescott, D.M. (1995). Macronuclear gene-sized molecules of hypotrichs. Nucleic Acids Res. 23, 1279–1283.Google Scholar
Ifrah, G. (2000). The Universal History of Numbers: From Prehistory to the Invention of the Computer. John Wiley & Sons, New York.Google Scholar
Ilardo, M., Meringer, M., Freeland, S.J., Rasulev, B. & Cleaves, H.J. 2nd (2015). Extraordinarily adaptive properties of the genetically encoded amino acids. Sci. Rep. 5, 9414.Google Scholar
Isenbarger, T.A., Carr, C.E., Johnson, S.S., Finney, M., Church, G.M., Gilbert, W., Zuber, M.T. & Ruvkun, G. (2008). The most conserved genome segments for life detection on Earth and other planets. Orig. Life Evol. Biosph. 38, 517–533.Google Scholar
Ivanova, N.N., Schwientek, P., Tripp, H.J., Rinke, C., Pati, A., Huntemann, M., Visel, A., Woyke, T., Kyrpides, N.C. & Rubin, E.M. (2014). Stop codon reassignments in the wild. Science 344, 909–913.Google Scholar
Kaplan, R. (1999). The Nothing That Is: A Natural History of Zero. Oxford University Press, Oxford.Google Scholar
Knight, R.D., Freeland, S.J. & Landweber, L.F. (1999). Selection, history and chemistry: the three faces of the genetic code. Trends Biochem. Sci. 24, 241–247.Google Scholar
Knight, R.D., Freeland, S.J. & Landweber, L.F. (2001). Rewiring the keyboard: evolvability of the genetic code. Nat. Rev. Genet. 2, 49–58.Google Scholar
Koonin, E.V. (2011). The Logic of Chance: The Nature and Origin of Biological Evolution. FT Press, Upper Saddle River.Google Scholar
Koonin, E.V. & Novozhilov, A.S. (2009). Origin and evolution of the genetic code: the universal enigma. IUBMB Life 61, 99–111.Google Scholar
Koonin, E.V. & Novozhilov, A.S. (2017). Origin and evolution of the universal genetic code. Annu. Rev. Genet 51. doi: 10.1146/annurev-genet-120116-024713.CrossRefGoogle ScholarPubMed
Kouwenhoven, M.B.N., Shu, Q., Cai, M.X. & Spurzem, R. (2016). Planetary systems in star clusters. Proc. Cosmic-Lab: Star Clusters as Cosmic Laboratories for Astrophysics, Dynamics, and Fundamental Physics - MODEST16. arXiv:1609.00898 [astro-ph.EP].Google Scholar
Lagerkvist, U. (1978). ‘Two out of three’: an alternative method for codon reading. Proc. Natl. Acad. Sci. USA 75, 1759–1762.CrossRefGoogle ScholarPubMed
Lajoie, M.J., Kosuri, S., Mosberg, J.A., Gregg, C.J., Zhang, D. & Church, G.M. (2013). Probing the limits of genetic recoding in essential genes. Science 342, 361–363.Google Scholar
Lajoie, M.J., Söll, D. & Church, G.M. (2016). Overcoming challenges in engineering the genetic code. J. Mol. Biol. 428, 1004–1021.CrossRefGoogle ScholarPubMed
Lemarchand, G. & Lomberg, J. (2009). Universal cognitive maps and the search for intelligent life in the universe. Leonardo 42, 396–402.Google Scholar
Lineweaver, C.H. (2001). An estimate of the age distribution of terrestrial planets in the universe: quantifying metallicity as a selection effect. Icarus 151, 307–313.Google Scholar
Liu, C.C. & Schultz, P.G. (2010). Adding new chemistries to the genetic code. Annu. Rev. Biochem. 79, 413–444.Google Scholar
Lobkovsky, A.E. & Koonin, E.V. (2012). Replaying the tape of life: quantification of the predictability of evolution. Front. Genet. 3, 1–8.Google Scholar
Lotman, Yu. M., Uspensky, B.A. & Mihaychuk, G. (1978). On the semiotic mechanism of culture. New Lit. Hist. 9, 211–232.Google Scholar
Makukov, M.A. & shCherbak, V.I. (2014). Space ethics to test directed panspermia. Life Sci. Space Res. 3, 10–17.Google Scholar
Maraia, R.J. & Iben, J.R. (2014). Different types of secondary information in the genetic code. RNA 20, 977–984.CrossRefGoogle ScholarPubMed
Martínez-Barbosa, C.A., Brown, A.G.A., Boekholt, T., Portegies Zwart, S., Antiche, E. & Antoja, T. (2016). The evolution of the Sun's birth cluster and the search for the solar siblings with Gaia. Mon. Not. R. Astron. Soc. 457, 1062–1075.Google Scholar
Marx, G. (1979). Message through time. Acta Astronaut. 6, 221–225.Google Scholar
Marx, G. (1986). The problem of simultaneity. In The Problem of the Search for Life in the Universe: Proceedings of the SETI Symposium in Tallinn, ed. Ambartsumian, V.A., Kardashev, N.S. & Troitsky, V.S., pp. 74–81. Nauka, Moscow (in Russian).Google Scholar
Massey, S.E. (2016). The neutral emergence of error minimized genetic codes superior to the standard genetic code. J. Theor. Biol. 408, 237–242.Google Scholar
Mautner, M.N. (1997). Directed panspermia. 3. Strategies and motivation for seeding star-forming clouds. J. Brit. Interplanet. Soc. 50, 93–102.Google Scholar
Mautner, M.N. (2000). Seeding the Universe with Life: Securing Our Cosmological Future. Legacy Books, Weston.Google Scholar
Mautner, M.N. (2009). Life-centered ethics, and the human future in space. Bioethics 23, 433–440.Google Scholar
Mazur, J. (2014). Enlightening Symbols: A Short History of Mathematical Notation and its Hidden Powers. Princeton University Press, Princeton.Google Scholar
McGhee, G. (2011). Convergent Evolution: Limited Forms Most Beautiful. The MIT Press, London.Google Scholar
Melosh, H.J. (2003). Exchange of meteorites (and life?) between stellar systems. Astrobiology 3, 207–215.Google Scholar
Meot-Ner, M. & Matloff, G.L. (1979). Directed panspermia – a technical and ethical evaluation of seeding nearby solar systems. J. Br. Interplanet. Soc. 32, 419–423.Google Scholar
Meyer, F., Schmidt, H.J., Plümper, E., Hasilik, A., Mersmann, G., Meyer, H.E., Engström, A. & Heckmann, K. (1991). UGA is translated as cysteine in pheromone 3 of Euplotes octocarinatus. Proc. Natl. Acad. Sci. USA 88, 3758–3761.Google Scholar
Mileikowsky, C., Cucinotta, F.A., Wilson, J.W., Gladman, B., Horneck, G., Lindegren, L., Melosh, J., Rickman, H., Valtonen, M. & Zheng, J.Q. (2000). Natural transfer of viable microbes in space. 1. From Mars to Earth and Earth to Mars. Icarus 145, 391–427.Google Scholar
NC-IUB – Nomenclature Committee of the International Union of Biochemistry (1985). Nomenclature for incompletely specified bases in nucleic acid sequences: recommendations 1984. Nucleic Acids Res. 13, 3021–3030.Google Scholar
Novozhilov, A.S., Wolf, Y.I. & Koonin, E.V. (2007). Evolution of the genetic code: partial optimization of a random code for robustness to translation error in a rugged fitness landscape. Biol. Dir. 2, 24.Google Scholar
Ostrov, N. et al. (2016). Design, synthesis, and testing toward a 57-codon genome. Science 353, 819–822.Google Scholar
Pfalzner, S. (2013). Early evolution of the birth cluster of the solar system. Astron. Astrophys. 549, A82.CrossRefGoogle Scholar
Philip, G.K. & Freeland, S.J. (2011). Did evolution select a nonrandom ‘alphabet’ of amino acids? Astrobiology 11, 235–240.Google Scholar
Plotkin, J.B. & Kudla, G. (2011). Synonymous but not the same: the causes and consequences of codon bias. Nat. Rev. Genet. 12, 32–42.CrossRefGoogle Scholar
Roberts, F.S. & Tesman, B. (2009). Applied Combinatorics. CRC Press, Boca Raton.CrossRefGoogle Scholar
Rodin, A.S., Szathmáry, E. & Rodin, S.N. (2011). On origin of genetic code and tRNA before translation. Biol. Dir. 6, 14.Google Scholar
Ronneberg, T.A., Landweber, L.F. & Freeland, S.J. (2000). Testing a biosynthetic theory of the genetic code: fact or artifact? Proc. Natl. Acad. Sci. USA 97, 13690–13695.Google Scholar
Rospars, J.-P. (2010). Terrestrial biological evolution and its implication for SETI. Acta Astronaut. 67, 1361–1365.Google Scholar
Rumer, Y.B. (1966). Systematization of codons in the genetic code. Proc. USSR Acad. Sci. 167, 1393–1394 (in Russian).Google ScholarPubMed
Rumer, Y.B. (2016). Translation of ‘Systematization of codons in the genetic code [I]’ by Yu. B. Rumer (1966). Phil. Trans. R. Soc. A 374, 20150446.Google Scholar
Sagan, C., Drake, F., Druyan, A., Ferris, T., Lomberg, J. & Sagan, L.S. (1978). Murmurs of Earth: The Voyager Interstellar Record. Random House, New York.Google Scholar
Sebeok, T.A. (2001). Signs: An Introduction to Semiotics, 2nd edn. University of Toronto Press, Toronto.Google Scholar
Seife, C. (2000). Zero: The Biography of a Dangerous Idea. Penguin Books, New York.Google Scholar
Shcherbak, V.I. (1988). The co-operative symmetry of the genetic code. J. Theor. Biol. 132, 121–124.Google Scholar
Shcherbak, V.I. (1989). The information artefact of the genetic code. Orig. Life Evol. Biosph. 19, 364–365.Google Scholar
shCherbak, V.I. & Makukov, M.A. (2013). The ‘Wow! signal’ of the terrestrial genetic code. Icarus 224, 228–242.Google Scholar
Shklovskii, I.S. & Sagan, C. (1966). Intelligent Life in the Universe. Holden-Day, San Francisco.Google Scholar
Sleator, R. & Smith, N. (2017). Directed panspermia: a 21st century perspective. Sci. Prog. 100, 187–193.Google Scholar
Sukhotin, B.V. (1971). Methods of message decoding. In Extraterrestrial Civilizations: Problems of Interstellar Communication, ed. Kaplan, S.A., pp. 133–212. NASA Technical Translations, F-631 (translated from Russian, 1969, Nauka, Moscow).Google Scholar
Swart, E.C., Serra, V., Petroni, G. & Nowacki, M. (2016). Genetic codes with no dedicated stop codon: context-dependent translation termination. Cell 166, 691–702.Google Scholar
Tepfer, D. (2008). The origin of life, panspermia and a proposal to seed the Universe. Plant Sci. 175, 756–760.Google Scholar
Vakoch, D.A. (1998a). Constructing messages to extraterrestrials: an exosemiotic perspective. Acta Astronaut. 42, 697–704.Google Scholar
Vakoch, D.A. (1998b). Signs of life beyond Earth: a semiotic analysis of interstellar messages. Leonardo 31, 313–319.Google Scholar
Vakoch, D.A. (2011). Responsibility, capability, and Active SETI: policy, law, ethics, and communication with extraterrestrial intelligence. Acta Astronaut. 68, 512–519.Google Scholar
Vakoch, D.A. (eds) (2014). Extraterrestrial Altruism: Evolution and Ethics in the Cosmos. Springer, Berlin.Google Scholar
Valtonen, M., Nurmi, P., Zheng, J.Q., Cucinotta, F.A., Wilson, J.W., Horneck, G., Lindegren, L., Melosh, J., Rickman, H. & Mileikowsky, C. (2009). Natural transfer of viable microbes in space from planets in extra-solar systems to a planet in our solar system and vice versa. Astrophys. J. 690, 210–215.Google Scholar
Ward, P.D. & Brownlee, D. (2003). Rare Earth: Why Complex Life Is Uncommon in the Universe. Copernicus Books, New York.Google Scholar
Webb, S. (2015). If the Universe Is Teeming with Aliens … Where Is Everybody? Seventy-Five Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life, 2nd edn. Springer.Google Scholar
Weiss, M.C., Sousa, F.L., Mrnjavac, N., Neukirchen, S., Roettger, M., Nelson-Sathi, S. & Martin, W.F. (2016). The physiology and habitat of the last universal common ancestor. Nat. Microbiol. 1, 16116.Google Scholar
Wilhelm, T. & Nikolajewa, S. (2004). A new classification scheme of the genetic code. J. Mol. Evol. 59, 598–605.Google Scholar
Wong, J.T.-F. (1975). A co-evolution theory of the genetic code. Proc. Natl. Acad. Sci. USA 72, 1909–1912.CrossRefGoogle ScholarPubMed
Wong, P.C., Wong, K. & Foote, H. (2003). Organic data memory using the DNA approach. Commun. ACM 46, 95–98.Google Scholar
Yarus, M., Widmann, J.J. & Knight, R. (2009). RNA-amino acid binding: a stereochemical era for the genetic code. J. Mol. Evol. 69, 406–429.Google Scholar
Yokoo, H. & Oshima, T. (1979). Is bacteriophage φX174 DNA a message from an extraterrestrial intelligence? Icarus 38, 148–153.Google Scholar
Zaitsev, A. (2012). Classification of interstellar radio messages. Acta Astronaut. 78, 16–19.Google Scholar
Zhang, J. & Norman, D.A. (1995). A representational analysis of numeration systems. Cognition 57, 271–295.Google Scholar
Zhang, Z. & Yu, J. (2011). On the organizational dynamics of the genetic code. Genomics Proteomics Bioinformatics 9, 21–29.CrossRefGoogle ScholarPubMed

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