“What we find is that the plants in Massachusetts are flowering dramatically earlier than Thoreau’s times but that the birds are changing a little bit — a detectable amount but not as much as the plants,” said Primack. “At the meeting on Thursday, I’ll tell people all these results we’ve found and emphasize that Thoreau could be called the climate change scientist.”

Pictured: Richard Smith who portrays David Henry Thoreau, in front of the replica of Thoreau’s cabin at Walden Pond in 2001.