http://www.nytimes.com/2014/03/02/magazine/the-mammoth-cometh.html?hp&_r=0 Not quite Jurassic Park, but still interesting. I tend to think bringing back megafauna to the wild would be a bad idea. Reintroducing creatures wiped out in the last 2500 years, however, seems like a good idea. Also, helping with nearly extinct creatures.
Also mammoths are the best source of grand souls for low level characters so more of them would be ok too
I would support the bolded, but it seems like resurrecting species would be opening Pandora's Box. That said, if there's a way to do it, someone eventually will. And I want on the waiting list for a sabre toothed tiger.
Wooly Mammoths and global warming would go together like intravenous drug users and unprotected sex.* *Best I could come up with on the spot.
Because some things we consider "normal" would seem post-apocalyptic to our great great grand parents. The lack of passenger pigeons being an example. also, why not have Steller's Sea Cows? The only reason they don't exist is because humans went nuts for them. etc etc.