The wolf -- known as No. 2 -- who led that species to successful re-establishment in Yellowstone has died, pushed aside by the next generation that No. 2 made possible, says Doug Smith, Yellowstone's lead wolf biologist, in a Billings Gazette story published today. "He was not a strong presence but a solid one," Doug told the newspaper. "He was a great hunter and a great provider for his pups. He did his job. [...] He was a mammoth wolf with one of the biggest, bushiest tails I've ever seen. But he was old, 8 years old, and a step slower."