More than a century and a half have passed since Walden was first published, and the world is now a very different place. Lakes are changing rapidly, not because we are separate from nature but because we are so much a part of it. While many of our effects on the natural world today are new, from climate change to nuclear fallout, our connections to it are ancient, as core samples from lake beds reveal. In Still Waters, Curt Stager introduces us...