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Why are scientists uncertain about whether de-extinct animals should be classified as the original species?

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Replica of a woolly mammoth with long curved tusks and shaggy fur on display in a museum exhibit, set against a dramatic painted landscape backdrop. — de-extinction The woolly mammoth (*Mammuthus primigenius*)—represented here by a replica in a Canadian museum—is an example of an extinct species that someday could be resurrected through de-extinction.

Scientists are uncertain about whether de-extinct animals should be classified as the original species primarily because these resurrection methods—such as back breeding, cloning, and genetic reconstruction—often result in organisms that diverge from the original species' genetic constitution.1

Because these techniques rely on modern surrogates or edited genomes to fill in gaps or approximate traits, the resulting animals may not be identical to their extinct ancestors. This potential for genetic divergence creates significant taxonomic ambiguity, as it is unclear whether these resurrected individuals truly represent the original species or merely a modern proxy that is morphologically or genetically similar. Furthermore, the long-term viability and health of these animals, as well as their ability to adapt to current environments, remain unknown, complicating their status as representatives of the species they are intended to replace.1