To ensure long-term survival of humans and Earth life generally, strategies need to be in place to recolonize Earth after global catastrophes and to colonize exoplanets. In one strategy of space colonization, the physical barriers erected by time and space are circumvented by sending cryopreserved human and animal embryos to exoplanets rather than adult crews. There the embryos would be developed to neonates in artificial uterus (AU) systems. A similar strategy could also be used to repopulate Earth after human extinction events. In this paper, we review the status and future prospects of these embryonic survival strategies. A critical requirement in each scenario is an AU system for complete ectogenesis, i.e. complete development of embryos to neonates outside the natural womb. While such systems do not yet exist, they may soon be developed to afford clinical assistance to infertile women and reproductive choices to prospective parents. In human survival schemes, AU systems would likely first be used to extend conventional survival missions (e.g. subterranean bunkers) by replacing some adult crew members with cryopreserved embryos. For major mass extinctions and all far future events, adult crews would be entirely replaced by embryos and androids. The most advanced missions would feature orbiting embryo spacecraft for Earth recolonization and analogous interstellar spacecraft for colonizing exoplanets. We conclude that an advanced civilization using such an integrated, embryonic approach could eventually colonize distant parts of its home galaxy and potentially the wider universe.

中文翻译：

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Android Noahs 和胚胎方舟：全球灾难生存和太空殖民中的外生

为了确保人类和地球生命的长期生存，需要制定战略，在全球灾难后重新殖民地球并殖民系外行星。在太空殖民的一种策略中，通过将冷冻保存的人类和动物胚胎送到系外行星而不是成年船员来绕过时间和空间建立的物理屏障。在那里，胚胎将在人工子宫 (AU) 系统中发育成新生儿。类似的策略也可用于在人类灭绝事件后重新填充地球。在本文中，我们回顾了这些胚胎生存策略的现状和未来前景。每种情况下的一个关键要求是用于完全外生的 AU 系统，即胚胎在自然子宫外完全发育成新生儿。虽然这样的系统还不存在，它们可能很快就会被开发出来，为不育妇女提供临床援助，并为准父母提供生殖选择。在人类生存计划中，AU 系统可能首先用于扩展传统的生存任务（例如地下掩体），方法是用冷冻保存的胚胎替换一些成年船员。对于重大的大规模灭绝和所有遥远的未来事件，成年船员将完全被胚胎和机器人取代。最先进的任务将包括用于地球再殖民的轨道胚胎航天器和用于殖民系外行星的类似星际航天器。我们得出的结论是，使用这种综合的、初步的方法的先进文明最终可能会在其母星系的遥远部分以及更广阔的宇宙中殖民。