a 100-million-year time advantage over the next oldest civilization, then it is conceivable that they could be in the singular position of being able to control, monitor, influence or isolate the emergence of every civilization that follows within their sphere of influence. This is analogous to what happens on Earth within our own civilization on a daily basis, in that everyone born on this planet is born into a pre-existing system of familial associations, customs, traditions and laws that were already long established before our birth and which we have little or no control over. METI (Messaging Extraterrestrial Intelligence) Overcoming the zoo hypothesis is one of the goals of METI, an organization created in 2015 to communicate with extraterrestrials, an active form of the search for extraterrestrials (SETI). METI, however, has been criticized for not representing humanity's collective will and for potentially endangering humanity. Criticism Some critics of the hypothesis say that only a single dissident group in an alien civilization, or alternatively the existence of galactic cliques instead of a unified galactic club, would be enough to break the pact of no contact. To Stephen Webb, it seems unlikely, taking humans as reference, that such prohibition would be in effect for millions of years without a single breach thereof. Others say that the zoo hypothesis, along with its planetarium variation, is highly speculative and more aligned with theological theories. One possible counterargument to the dissident (rogue) group argument is that extraterrestrial artificial superintelligences dominate space, including space occupied by biological intelligences; moreoever, separate artificial superintelligences are assumed to tend towards a network of merged superintelligencies, thereby dissuading rogue behaviour. Appearance in fiction The zoo hypothesis is a common theme in science fiction. 1930s 1937: In Olaf Stapledon's 1937 novel Star Maker, great care is taken by the Symbiont race to keep its existence hidden from "pre-utopian" primitives, "lest they should lose their independence of mind.” It is only when such worlds become utopian-level space travellers that the Symbionts make contact and bring the young utopia to an equal footing. 1950s 1951: Arthur C. Clarke's The Sentinel (first published in 1951) and its later novel adaptation 2001: A Space Odyssey (1968) feature a beacon which is activated when the human race discovers it on the moon. 1953: In Childhood's End, a novel by Arthur C. Clarke published in 1953, the alien cultures had been observing and registering Earth's evolution and