We must protect every species still in existence being wiped out by ourselves because they are still part of important food webs that, if broken, could upset the balance for other species and start a chain-reaction of die-offs. There is no need to protect a species that is long gone even before we came on to the scene. Especially when there is no room on this Earth for them but in captivity. We successfully introduce dinosaurs to the wild (if they could even be revived and rehabilitated, thankfully not) and we risk losing some of our modern species of animal. We keep them in captivity, well, it's not much a life for them is it?