It started in 2002: The bears around Durango, Colorado, came down from the hills to feast on the city’s garbage. Normally, natural food—nuts and berries and acorns—keeps them in the woods, but a series of droughts and late freezes in 2002, 2007, 2012 and 2017 left them hungry. Despite their fear of...

Sometimes my most significant revelations are the annoying, kick-me-in-the-pants ones that follow a period of contented denial. One of those seismic shifts in thought came last year at a dinner party, when a man nearly half my age honed in on a flaw in logic I’d subconsciously buried. A plant...