Editing Fermi paradox (section)

==== Earth is deliberately being avoided ====
{{main|Zoo hypothesis}}
The [[zoo hypothesis]] states that intelligent extraterrestrial life exists and does not contact life on Earth to allow for its natural evolution and development.<ref name=":1">{{cite journal| last1=Ball| first1=J| title=The zoo hypothesis| journal=Icarus| volume=19|issue=3|pages=347–349|date=1973| doi=10.1016/0019-1035(73)90111-5| bibcode=1973Icar...19..347B}}</ref> A variation on the zoo hypothesis is the laboratory hypothesis, where humanity has been or is being subject to experiments,<ref name=":1" /><ref name=":0" /> with Earth or the Solar System effectively serving as a laboratory. The zoo hypothesis may break down under the [[uniformity of motive]] flaw: all it takes is a single culture or civilization to decide to act contrary to the imperative within humanity's range of detection for it to be abrogated, and the probability of such a violation of hegemony increases with the number of civilizations,<ref name=cr /><ref>{{Cite journal|last=Forgan|first=Duncan H.|date=2011-06-08|title=Spatio-temporal constraints on the zoo hypothesis, and the breakdown of total hegemony|journal=International Journal of Astrobiology|volume=10|issue=4|pages=341–347|doi=10.1017/s147355041100019x|arxiv=1105.2497|bibcode=2011IJAsB..10..341F|s2cid=118431252|issn=1473-5504}}</ref> tending not towards a "Galactic Club" with a unified foreign policy with regard to life on Earth but multiple "Galactic Cliques".<ref>{{Cite journal|last=Forgan|first=Duncan H.|date=2016-11-28|title=The Galactic Club or Galactic Cliques? Exploring the limits of interstellar hegemony and the Zoo Hypothesis|journal=International Journal of Astrobiology|volume=16|issue=4|pages=349–354|doi=10.1017/s1473550416000392|arxiv=1608.08770 |hdl=10023/10869|s2cid=59041278|issn=1473-5504|hdl-access=free}}</ref> However, if [[artificial superintelligence]]s dominate galactic life, and if it is true that such intelligences tend towards merged hegemonic behavior, then this would address the uniformity of motive flaw by dissuading rogue behavior.<ref>{{Cite journal |last=Visscher |first=Alex De |date=2020 |title=Artificial versus biological intelligence in the Cosmos: clues from a stochastic analysis of the Drake equation |url=https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/abs/artificial-versus-biological-intelligence-in-the-cosmos-clues-from-a-stochastic-analysis-of-the-drake-equation/7BC4932CD94887E338B2DA55488DE8C6 |journal=International Journal of Astrobiology |language=en |volume=19 |issue=5 |pages=353–359 |doi=10.1017/S1473550420000129 |arxiv=2001.11644 |bibcode=2020IJAsB..19..353D |s2cid=211003646 |issn=1473-5504}}</ref>

Analysis of the inter-arrival times between civilizations in the galaxy based on common astrobiological assumptions suggests that the initial civilization would have a commanding lead over the later arrivals. As such, it may have established what has been termed the ''zoo hypothesis'' through force or as a galactic or universal norm and the resultant "paradox" by a cultural [[founder effect]] with or without the continued activity of the founder.<ref>{{cite journal |last1=Hair |first1=Thomas W. |title=Temporal dispersion of the emergence of intelligence: an inter-arrival time analysis |journal=International Journal of Astrobiology |date=February 25, 2011 |volume=10 |issue=2 |pages=131–135 |doi=10.1017/S1473550411000024|bibcode=2011IJAsB..10..131H |s2cid=53681377 }}</ref> Some colonization scenarios predict spherical expansion across star systems, with continued expansion coming from the systems just previously settled. It has been suggested that this would cause a strong [[natural selection|selection]] process among the colonization front favoring cultural or biological [[adaptation]]s to living in starships or space habitats. As a result, they may forgo living on planets.<ref name="David Brin, 1983, abandonment of planet-dwelling">"The Great Silence: the Controversy Concerning Extraterrestrial Intelligent Life" (15-page paper), ''Quarterly J. Royal Astron. Soc.,'' David Brin, 1983, [http://adsbit.harvard.edu//full/1983QJRAS..24..283B/0000300.000.html p. 300 " ... abandonment of planet-dwelling ... "] {{Webarchive|url=https://web.archive.org/web/20190406165950/http://adsbit.harvard.edu//full/1983QJRAS..24..283B/0000300.000.html|date=April 6, 2019}}.</ref> This may result in the destruction of terrestrial planets in these systems for use as building materials, thus preventing the development of life on those worlds. Or, they may have an ethic of protection for "nursery worlds", and protect them.<ref name="David Brin, 1983, abandonment of planet-dwelling" />

It is possible that a civilization advanced enough to travel between solar systems could be actively visiting or observing Earth while remaining undetected or unrecognized.<ref>{{cite journal |title=What Role Will Extraterrestrials Play in Humanity's Future? |author=Tough, Allen |journal=Journal of the British Interplanetary Society |volume=39 |issue=11 |pages=492–498 |year=1986 |url=http://ww.w.ieti.org/articles/future.pdf |bibcode=1986JBIS...39..491T |access-date=June 27, 2015 |archive-url=https://web.archive.org/web/20150630051853/http://ww.w.ieti.org/articles/future.pdf |archive-date=June 30, 2015 |url-status=live }}</ref> Following this logic, and building on arguments that other proposed solutions to the Fermi paradox may be implausible, [[Ian Crawford (astrobiologist)|Ian Crawford]] and [[Dirk Schulze-Makuch]]<ref>{{cite journal|last1=Crawford|first1= Ian|last2=Schulze-Makuch|first2=Dirk|date=2024 |title=Is the apparent absence of extraterrestrial technological civilisations down to the zoo hypothesis or nothing?|url=https://www.nature.com/articles/s41550-023-02134-2|journal=Nature Astronomy|volume= 8|issue= 1|pages=44–49|doi= 10.1038/s41550-023-02134-2|bibcode=2024NatAs...8...44C }}</ref> have argued that technological civilisations are either very rare in the Galaxy or are deliberately hiding from us.