Biological Theory

, Volume 13, Issue 2, pp 131–141 | Cite as

The Evolutionary Psychology of Extraterrestrial Intelligence: Are There Universal Adaptations in Search, Aversion, and Signaling?

  • Peter M. Todd
  • Geoffrey F. Miller
Thematic Issue Article: Astrobiology


To understand the possible forms of extraterrestrial intelligence (ETI), we need not only astrobiology theories about how life evolves given habitable planets, but also evolutionary psychology theories about how intelligence emerges given life. Wherever intelligent organisms evolve, they are likely to face similar behavioral challenges in their physical and social worlds. The cognitive mechanisms that arise to meet these challenges may then be copied, repurposed, and shaped by further evolutionary selection to deal with more abstract, higher-level cognitive tasks such as conceptual reasoning, symbolic communication, and technological innovation, while retaining traces of the earlier adaptations for solving physical and social problems. These traces of evolutionary pathways may be leveraged to gain insight into the likely cognitive processes of ETIs. We demonstrate such analysis in the domain of search strategies and show its application in the domains of emotional aversions and social/sexual signaling. Knowing the likely evolutionary pathways to intelligence will help us to better search for and process any alien signals from the search for ETIs (SETI) and to assess the likely benefits, costs, and risks of humans actively messaging ETIs (METI).


Aversions Evolutionary psychology Extraterrestrial intelligence METI (messaging extraterrestrial intelligence) Search strategies SETI (search for extraterrestrial intelligence) Social signaling 



We thank Anna Dornhaus, Tom Schoenemann, Linnda Caporael, and two reviewers for helpful comments and pointers on an earlier draft and Deborah Klosky for careful editing. Part of this work was supported by the John Templeton Foundation grant, “What drives human cognitive evolution,” to the first author.


  1. Barkow JH (2017) The evolutionary psychology of extraterrestrials. In: Vakoch D (ed) Extraterrestrial intelligence: cognition and communication in the universe (forthcoming)Google Scholar
  2. Barrett HC, Todd PM, Miller GF, Blythe PW (2005) Accurate judgments of intention from motion cues alone: a cross-cultural study. Evol Hum Behav 26(4):313–331CrossRefGoogle Scholar
  3. Bell WJ (1991) Searching behaviour: the behavioural ecology of finding resources. Chapman and Hall, LondonGoogle Scholar
  4. Bradbury JW, Vehrencamp SL (2011) Principles of animal communication, 2nd edn. Sinauer, SunderlandGoogle Scholar
  5. Charnov EL (1976) Optimal foraging, the marginal value theorem. Theor Popul Biol 9(2):129–136CrossRefGoogle Scholar
  6. Cosmides L, Tooby J (1997) Evolutionary psychology: a primer. Retrieved from Accessed 1 May 2017
  7. Di Stefano R, Ray A (2016) Globular clusters as cradles of life and advanced civilizations.
  8. Dornhaus A (2017) Aliens are likely to be smart but not ‘intelligent’: what evolution of cognition on Earth tells us about extraterrestrial intelligence. In: Vakoch D (ed) Extraterrestrial intelligence: cognition and communication in the universe (forthcoming)Google Scholar
  9. Gibson JJ (1979) The ecological approach to visual perception. Houghton Mifflin, BostonGoogle Scholar
  10. Gigerenzer G, Todd PM, ABC Research Group (1999) Simple heuristics that make us smart. Oxford University Press, New YorkGoogle Scholar
  11. Gigerenzer G, Hertwig R, Pachur T (eds) (2011) Heuristics: the foundations of adaptive behavior. Oxford University Press, New YorkGoogle Scholar
  12. Haselton MG, Miller GF (2006) Women’s fertility across the cycle increases the short-term attractiveness of creative intelligence. Human Nature 17(1):50–73CrossRefGoogle Scholar
  13. Hills TT (2006) Animal foraging and the evolution of goal-directed cognition. Cogn Sci 30:3–41CrossRefGoogle Scholar
  14. Hills TT, Todd PM (2008a) Population heterogeneity and individual differences in an assortative agent-based marriage and divorce model (MADAM) using search with relaxing expectations. J Artif Soc Soc Simul 11:5Google Scholar
  15. Hills TT, Todd PM, Goldstone RL (2008b) Search in external and internal spaces: evidence for generalized cognitive search processes. Psychol Sci 19(8):802–808CrossRefGoogle Scholar
  16. Hills TT, Jones MN, Todd PM (2012) Optimal foraging in semantic memory. Psychol Rev 119:431–440CrossRefGoogle Scholar
  17. Hills TT, Todd PM, Lazer D et al (2015) Exploration versus exploitation in space, mind, and society. Trends Cogn Sci 19(1):46–54CrossRefGoogle Scholar
  18. Holloway RL (1969) Culture: a human domain. Curr Anthropol 10:395–412CrossRefGoogle Scholar
  19. Hutchinson JM, Wilke A, Todd PM (2008) Patch leaving in humans: can a generalist adapt its rules to dispersal of items across patches? Anim Behav 75:1331–1349CrossRefGoogle Scholar
  20. James W (1890) Principles of psychology. Henry Holt, New YorkGoogle Scholar
  21. Johnson S (2017), June 28. Greetings ET (please don’t murder us). New York Times Magazine. Retrieved from Accessed 30 June 2017
  22. Krebs JR, Dawkins R (1984) Animal signals: mind-reading and manipulation. Behav Ecol 2:380–402Google Scholar
  23. Liu C (2015) The dark forest. Tor, New YorkGoogle Scholar
  24. METI International (2016) Strategic plan, 2015—2018. Accessed 11 Sept 2017
  25. Miller GF (2000a) The mating mind: how sexual choice shaped the evolution of human nature. Viking, New YorkGoogle Scholar
  26. Miller GF (2000b) Sexual selection for indicators of intelligence. In: Gregory B, Jamie G, Kate W (eds) The nature of intelligence (Novartis Foundation Symposium 233). Wiley, New York, pp 260–275Google Scholar
  27. Miller GF (2000c) Evolution of human music through sexual selection. In: Wallin NL, Brown S, Merker B (eds) The origins of music. MIT Press, Cambridge, pp 329–360Google Scholar
  28. Miller GF (2002) How did language evolve? In: Swain Harriet (ed) Big questions in science. Jonathan Cape, London, pp 79–90Google Scholar
  29. Miller GF (2007) Reconciling evolutionary psychology and ecological psychology: how to perceive fitness affordances. Acta Psychol Sin 39(3):546–555Google Scholar
  30. Miller GF (2012) Sex, mutations, and marketing. EMBO Rep 13(10):880–884CrossRefGoogle Scholar
  31. Miller GF, Todd PM (1998) Mate choice turns cognitive. Trends Cogn Sci 2(5):190–198CrossRefGoogle Scholar
  32. Oaten M, Stevenson RJ, Case TI (2009) Disgust as a disease-avoidance mechanism. Psychol Bull 135(2):303–321CrossRefGoogle Scholar
  33. Pirolli P (2007) Information foraging theory: adaptive interaction with information. Oxford University Press, New YorkCrossRefGoogle Scholar
  34. Rozin P, Todd PM (2016) The evolutionary psychology of food intake and food choice. In: Buss DM (eds) The handbook of evolutionary psychology, vol 1, 2nd edn. Wiley, Hoboken, pp 183–205Google Scholar
  35. Russell PS, Giner-Sorolla R (2013) Bodily moral disgust: what it is, how it is different from anger, and why it is an unreasoned emotion. Psychol Bull 139(2):328–351CrossRefGoogle Scholar
  36. Saad G, Eba A, Sejean R (2009) Sex differences when searching for a mate: a process-tracing approach. J Behav Decis Mak 22:171–190CrossRefGoogle Scholar
  37. Shostak S (2015) Should we keep a low profile in space? New York Times. Accessed 11 Sept 2017
  38. Stephens DW, Krebs JR (1986) Foraging theory. Princeton University Press, Princeton, NJGoogle Scholar
  39. Subotowicz M, Usowicz J, Paprotny Z (1979) On active and passive CETI from an earth satellite orbit. Acta Astronaut 6:203–212CrossRefGoogle Scholar
  40. Todd PM, Miller GF (1993) Parental guidance suggested: how parental imprinting evolves through sexual selection as an adaptive learning mechanism. Adapt Behav 2(1):5–47CrossRefGoogle Scholar
  41. Todd PM, Miller GF (2017) Cognitive exaptations for extra-terrestrial intelligence. In: Vakoch D (ed) Extraterrestrial intelligence: cognition and communication in the universe (forthcoming)Google Scholar
  42. Todd PM, Gigerenzer G, The ABC Research Group. (2012a) Ecological rationality: intelligence in the world. Oxford University Press, New YorkCrossRefGoogle Scholar
  43. Todd PM, Hills TT, Robbins TW (eds) (2012b) Cognitive search: evolution, algorithms, and the brain. Strüngmann Forum Reports, vol 9. MIT Press, CambridgeGoogle Scholar
  44. Tybur JM, Lieberman D, Kurzban R et al (2013) Disgust: evolved function and structure. Psychol Rev 120(1):65–84CrossRefGoogle Scholar
  45. Vakoch DA (2011) Asymmetry in active SETI: a case for transmissions from Earth. Acta Astronaut 68:476–488CrossRefGoogle Scholar
  46. Wason PK (2014) Inferring intelligence: prehistoric and extraterrestrial. In: Vakoch DA (ed) Archaeology, anthropology, and interstellar communication (pp 113–128). The NASA History Series SP-2013-4413. Washington, D.C.: NASA.
  47. Wilke A, Barrett HC (2009) The hot hand phenomenon as a cognitive adaptation to clumped resources. Evol Hum Behav 30:161–169CrossRefGoogle Scholar
  48. Wimsatt WC (2007) Re-engineering philosophy for limited beings: piecewise approximations to reality. Harvard University Press, CambridgeGoogle Scholar
  49. Winterhalder B, Smith EA (2000) Analyzing adaptive strategies: human behavioral ecology at twenty-five. Evol Anthropol 9:51–72CrossRefGoogle Scholar
  50. Wolfe JM (2013) When is it time to move to the next raspberry bush? Foraging rules in human visual search. J Vis 13:1–17Google Scholar
  51. Zahavi A (1975) Mate selection: a selection for a handicap. J Theor Biol 53:205–214CrossRefGoogle Scholar
  52. Zaitsev A (2006) Past–Present–Future. SETI League. Accessed 11 Sept 2017

Copyright information

© Konrad Lorenz Institute for Evolution and Cognition Research 2017

Authors and Affiliations

  1. 1.Cognitive Science Program and Department of Psychological and Brain SciencesIndiana UniversityBloomingtonUSA
  2. 2.Department of PsychologyUniversity of New MexicoAlbuquerqueUSA

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