"Modern scientists trying to understand climate change are engaged in an unlikely collaboration — with two beloved but long-dead nature writers: Henry David Thoreau and Aldo Leopold."

"The authors of Walden and A Sand County Almanac and last spring's bizarrely warm weather have helped today's scientists understand that the first flowers of spring can continue to bloom earlier, as temperatures rise to unprecedented levels."

"If you take the old historical records of Thoreau and Aldo Leopold and use those to sort of predict when plants will be flowering in an astonishingly warm year like we had in 2012, the flowering time of plants is exactly what you would predict using this historical data," says Boston University biology professor Richard Primack."