Henry David Thoreau endorsed civil disobedience, opposed slavery and lived for two years in a hut in the woods here, an experience he described in 'Walden.' Now he turns out to have another line in his résumé: climate researcher.
He did not realize it, of course. Thoreau died in 1862, when the industrial revolution was just beginning to pump climate-changing greenhouse gases into the atmosphere. In 1851, when he started recording when and where plants flowered in Concord, he was making notes for a book on the seasons.
Now, though, researchers at Boston University and Harvard are using those notes to discern patterns of plant abundance and decline in Concord -- and by extension, New England -- and to link those patterns to changing climate.
Their conclusions are clear. On average, common species are flowering seven days earlier than they did in Thoreau`s day, Richard B. Primack, a conservation biologist at Boston University, and Abraham J. ...