Poll: As scientists discuss the ethics of "de-extinction", which species would you like to bring back from the dead?

(Getty)

On Friday, a group of US scientists known as the Revive & Restore initiative will host a day long TEDx conference in Washington to talk about the ethics involved in bringing an extinct species back from the dead.

Revive & Restore are already hard at work on the North American passenger pigeon which was last seen alive almost a century ago, in 1914.

This wouldn't be the first time a de-extinction project has been successful. In 2009, the Pyrenean ibex, a kind of extinct mountain goat was cloned, but the clone only lived for a few minutes. There are currently also projects also underway to bring back the Tasmanian tiger, the California condor and the woolly mammoth.

So far, so exciting, but as anyone who's seen Jurassic Park will tell you, these projects can have unintended consequences...