Recent advances in synthetic biology have made it possible to revive extinct species of animals, a process known as ‘de-extinction’. This paper examines two reasons for supporting de-extinction: the potential for de-extinct species to play useful roles in ecosystems; and human valuing of certain de-extinct species. I focus on the particular case of passenger pigeons to argue that the most critical challenge for de-extinction is that it entails significant suffering for sentient individual animals. I also provide reasons to take existence (...) value, or valuing the mere the fact that a species exists, into consideration in debates over de-extinction. (shrink)

This review provides an overview of the ethics of extinctions with a focus on the Western analytical environmental ethics literature. It thereby gives special attention to the possible philosophical grounds for Michael Soulé’s assertion that the untimely ‘extinction of populations and species is bad’. Illustrating such debates in environmental ethics, the guiding question for this review concerns why – or when – anthropogenic extinctions are bad or wrong, which also includes the question of when that might not be the case (...) (i.e. which extinctions are even desirable). After providing an explanation of the disciplinary perspective taken (section “Introduction”), the concept of extinction and its history within that literature are introduced (section “Understanding extinction”). Then, in section “Why (or when) might anthropogenic extinctions be morally problematic?”, different reasons for why anthropogenic extinctions might be morally problematic are presented based on the loss of species’ value, harm to nonhuman individuals, the loss of valuable biological variety and duties to future generations. This section concludes by also considering cases where anthropogenic extinctions might be justified. Section “How to respond to extinctions?” then addresses a selection of topics concerning risks and de-extinction technologies. Finally, the section on “Extinction studies” introduces other viewpoints on the ethics of extinction from the extinction studies literature, followed by the “Conclusion”. (shrink)