People have been mailing stolen petrified wood back to Arizona’s Petrified Forest National Park for decades, often with apology letters blaming the rocks for years of bad luck. Car problems. Illness. Deaths in the family. Some people simply said life hadn’t felt right since taking the wood. The returned pieces became so common that park staff developed what researchers called a “conscience pile.” Because the original locations are usually unknown, putting the pieces back could interfere with the park’s scientific record. But there’s an even crazier part of the story. For years, signs warned visitors that 14 tons of petrified wood were supposedly being stolen annually. Researchers later tested how messages like that actually affected visitors. The result was basically the opposite of what you’d expect. A study involving thousands of visitors found that emphasizing how commonly other people stole petrified wood could actually increase theft, while messaging focused on telling peop...