Extracting DNA from ancient specimens and using cloning technology to resurrect extinct species has become a staple plot device of wildly popular science fiction novels and films since Jurassic Park. But the prospect that extinct animals may live again no longer belongs solely to the realm of science fiction. “De-extinction” is coming closer to reality, as scientists now are experimenting with a number of methods for resurrecting extinct species. No method will bring back the dinosaurs; it has been too long since the Jurassic era for their DNA to survive. It may well be possible to “resurrect” more recently extinct species, however, such as the Pyrenean ibex, the passenger pigeon, or possibly even the awe-inspiring woolly mammoth, in the not too distant future.

While some discussion of these exciting developments has appeared in the scientific and popular press, most articles focus on technical and ethical issues: can we do this, and should we? For purposes of this Article, we treat de-extinction, in some form, as a scientifically reasonable future prospect whose legal implications should be considered in a practical manner. For the most part, we assume that if de-extinction can feasibly be accomplished, someone will undertake the effort if for no other reason than because it would be irresistibly thrilling to do so. Jurassic Park itself may be unattainable, but a somewhat more plausible Pleistocene Park, populated with mammoths and aurochs, would generate nearly as much popular excitement. Other motivations for pursuing de-extinction might include the reintroduction of “keystone” species for purposes of reviving whole ecosystems, with substantial environmental benefits.

Therefore, this Article explores the implications of de-extinction under existing law. Part I introduces the current science of de-extinction and the different methods its proponents are pursuing. The methods are worth reviewing in some detail, since the implications of those methods are significant for legal outcomes. Part II discusses the ESA, whether it would apply to de-extinct species, and how it should be applied. Part III addresses permitting and evaluation of environmental impacts under NEPA for projects to reintroduce de-extinct species into the wild, by analogy to EISs for reintroductions of living but locally extirpated species into regions that they formerly inhabited and EISs for releases into the environment of genetically modified organisms (GMOs). Part IV explores the regulation of resurrected species as GMOs, given that two of the three de-extinction methods being pursued would result in GMOs. Part V considers the patentability of such GMOs. Part VI summarizes our conclusions.