Android Noahs and embryo Arks: ectogenesis in global catastrophe survival and space colonization

Abstract

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.

The Case for Technosignatures: Why They May Be Abundant, Long-lived, Highly Detectable, and Unambiguous

“…For instance, the biosignature search community is developing many mature frameworks for designing and interpreting the results of life detection experiments, including the development and selection of good biosignatures to search for, selection criteria and prioritization of target lists, and frameworks for determining the confidence of detection and dealing with ambiguity (Stark et al 2019;Truitt et al 2020;Tuchow & Wright 2020, 2021Neveu et al 2018;Green et al 2021, to give a few recent examples in addition to the references in Section 1).…”

“…The spread of life need not invoke enormous "generation ships" (Hein et al 2012) or warp drives: one can imagine many solutions to the difficulties of the very long journey between stars. For intsance, one might imagine cryostasis or even the re-generation of life "from scratch" by using artificial ova and DNA sequences stored in computer memory (e.g., Freitas 1983;Crowl et al 2012;Hippke et al 2018;Edwards 2021), andHansen &Zuckerman (2021) discuss how stellar motions mean that occasionally such trips can be quite short. Regardless, once it arrives at a new home, such life will almost certainly create technosignatures (since it used technology to get there), and some fraction of them may also eventually give rise to a new biosphere, as well.…”

The Ethical Status of Germline Gene Editing in Future Space Missions: The Special Case of Positive Selection on Earth for Future Space Missions

“…Life in space may be seen as either a necessity (when the continued existence of humans on Earth will be threatened) or an attractive possibility (as a place to live, work). This is only an assumption about the future, as it cannot be ruled out that the advanced program of space exploration and exploitation will be carried out exclusively by automated means, without human involvement [5], or that human rescue in the case of a hypothetical apocalyptic scenario will be accomplished by means of so-called embryo space colonization [11].…”

Humanity should colonize space in order to survive but not with embryo space colonization

“…In this paper, I refer only to the embryo space colonization (ESC) concept under the assumption that humanity will send cryopreserved embryos on a mission to an exoplanet lasting perhaps millions of years before extinction on Earth (Edwards, 2021). So, I am referring to a scenario in which there will not be a single living human for many millions of years, and the only form will be frozen embryos.…”