It’s no secret that humanity’s success on this planet we call Earth has come at a high cost. Since our ancestors began migrating out of Africa some 70,000 years ago, their passage and settlement have left marks on the natural environment and its species. In short, our ability to grow has always meant extinction for other species, be they other forms of high-order primates (such as Neanderthals) or animals hunted for their pelts and meat (such as wooly mammoths).

In fact, the Neolithic Revolution, which began some 15,000 years ago with the adoption of farming, was believed to have been motivated by the mass extinction of animals that were once hunted by our ancestors. And since that time, countless more species have been pushed to the brink or killed off entirely by our ever-expanding, consuming, and polluting ways. However, recent innovations in biology and bio-medicine might just be able to reverse this trend.

Last Friday, at a at a National Geographic-sponsored TEDx conference, scientists met in Washington, D.C. to discuss which animals we should bring back from extinction, as well as the means and ethics involved in doing so. They called it “de-extinction”, and considered which species they would consider restoring to existence. The conference resulted in a list of 24 species that were selected for restoration, as well as some guidelines for the selection process.

Those chosen were based on the following criteria and future selections will be determined the same way:

1. Are the species desirable — do they hold an important ecological function or are they beloved by humans?
2. Are the species practical choices — do we have access to tissue that could give us good quality DNA samples or germ cells to reproduce the species?
3. And are they able to be reintroduced to the wild — are the habitats in which they live available and do we know why they went extinct in the first place?

As you might imagine, dinosaurs didn’t make the cut. In addition to no longer serving and important ecological function, the habitats they once had access to are long gone (Earth’s climate and ecology have changed drastically since the Cretaceous Period), and most importantly, we no longer have access to their DNA.

Yes, despite what Michael Crichton told us, the DNA of dinosaur fossils is so far degraded that something like Jurassic Park would never be possible. And of course, despite being beloved by humans, they aren’t exactly safe customers to have around! But rest assured, the list of candidates is still very long.

Of the 24 species selected, the majority were families of birds which were pushed to extinction due to hunting, deforestation, urban sprawl, pollution, and loss of habitat. In addition, the famous Auroch, a species of cattle that is commemorated in myth but which actually existed until 1627. And then there’s the equally famous DoDo bird, the fearless bird which was rendered extinct by Portuguese settlers in its native Mauritius.

And then there’s the venerable Wooly Mammoth, the great shaggy member of the Elephantidae family which went extinct some 4000 years ago. Not only is this animals demise directly associated with humanity’s ascendance to the top of the food chain, it is something which may now be entirely reversible. Thanks to frozen, preserved carcasses of Mammoths, which are still found in the north to this day, scientists have access to well-preserved strands of their DNA.

And as already noted, the issue of cost, ethics and desirability featured pretty prominently in the conference. For starters, those present had to consider whether or not it would be a good idea to bring animals back from the brink seeing as how it was human agency that led to their extinction in the first place. Is the world any better off than it was hundreds or even thousands of years ago? Would these animals find new purchase, or just end up dying off again?

Second, there was the question of housing them and reintroducing them into the wild. Not only is it a question of them being able to find habitats again, it’s a question of whether or not we can ensure the kind of transition that would be needed. Sure, we’d all love to see Sabre-Tooth tigers alive and well again, but its not like we can just clone them and send them back out into the wild. Who’s to say how their reintroduction will impact species that are currently roaming about in the wild?

And of course, there was the consideration of what all this tampering amounts to. Given that human agency is responsible for all this loss of life, would resurrecting them simply be more of the same? Would we be, in effect, playing God and tampering with forces best left to nature? All good questions, and they force us to consider an alternative proposition.

Perhaps what would be best for the natural world and its remaining species would be for us to stop behaving so irresponsibly. Perhaps we should focus on sustainable living, cleaning up pollution, ending climate change, and getting our own population under control before we start trying to repopulate other species. Still, it is an intriguing possibility, and provides some reassurance that no matter how much damage we end up doing, that we might be able to undo some after the fact. Perhaps we just need to wait…

Too bad about Jurassic Park though. In the course of everything else discussed at this TED conference, I’m sure that the announcement that dinosaurs were as good as gone shattered the dreams of many an eccentric billionaire!

Sources: businessinsider.com, nationalgeographic.com