In a study published this week in the journal Nature, a team of scientists successfully sequenced 2M-year-old DNA from the northeastern tip of Greenland. The DNA sequence is the oldest obtained on record.
The region is a polar desert today, but this discovery paints a picture of a lush and verdant Greenland 2M years ago, rich in biodiversity, including elephant-like mastodons, reindeer, geese, birch and poplar trees, and sea life teaming with algae and horseshoe crabs.
Greenland's newly-discovered "lost world" is a close analog to what the region could look like if our current climate change trends continue unabated. This shows that plants and animals can evolve quickly in the face of a changing climate. The more we learn about similar eras of rapid change, the more information we have to anticipate and adjust to changes of the "hothouse Earth" of the near future.
Though a fascinating discovery, we can't extrapolate our climate future based on the lush Greenland of 2M years ago. The "lost world" ecosystem enjoyed longer warm periods between Ice Ages, allowing species to hang out nearby and repopulate Greenland at will. Many of the species that changed the face of Greenland back then are also extinct today, so it's better to appreciate breakthroughs in paleontology for their own sake without incorrectly projecting them on our climate situation today.