Forget the ancient woolly mammoth, efforts to resurrect vanished species should target those that are recently extinct, a New Zealand conservation biologist says.
Professor Philip Seddon, from Otago University's Department of Zoology, also says there should be determined efforts to prevent endangered species from dying out in the first place.
He says the prospect of bringing species back through cutting-edge technology like gene-editing has caught the imagination of scientists and the public alike.
He agrees that idea of resurrecting mammoths might have a "wow factor".
But in an editorial in the journal Functional Ecology, Prof Seddon argues that efforts would be better directed at species where conservation benefits are clearer.
"The ecological niches in which mammoths - or moa for instance - once lived, no longer exist in any meaningful way," he said.
"If we were to bring such species back, apart from just as scientific curios, these animals would likely be inherently maladapted to our modern eco-systems."
Instead, using cloning techniques to re-establish "proxies" of species that have recently become extinct should be the focus, along with trying to ensure the survival of endangered species.
"Extinction of any species marks a significant threshold that, once crossed, cannot be fully reversed, despite the apparent promise of powerful new technologies," Prof Seddon said.
He suggested de-extinction projects would inevitably be pursued.
"The reality of the idea is too sexy to ignore, and it could be driven by aesthetic, commercial, scientific, or some other hitherto unanticipated imperatives and motivations."