Two months ago (1 Steem was $2 then!) I wrote about recreating of arctic tundro-steppe in Northern Siberia: experimental program to transform lifeless arctic tundra to rich ecosystem with grazers, predators and even possibly mammoths.
Here is a good infographics about Pleistocene Park, and its ecosystem:
German ARD TV made very detailed documentary about Pleistocene Park. It is in German language, but video is very informative.