Is there an angel or a devil behind the mask? Scientists say it may not matter in terms of anonymous behavior. Joel Saget/AFP/Getty Images hide caption

itoggle caption Joel Saget/AFP/Getty Images

Five savory cupcakes: Chicken potpie, lasagna, grilled cheese, mac n' cheese and the Thanksgiving leftovers. Courtesy of @LisaSKim hide caption

itoggle caption Courtesy of @LisaSKim

Abraham Lincoln, circa 1850. Lincoln was a political non-entity before he was elected. Why is he more widely known to history than the presidents who came immediately before and after him? Hulton Archive/Getty Images hide caption

itoggle caption Hulton Archive/Getty Images

Actors Stan Laurel and Edna Marlon play at socializing around the campfire. It turns out that early man's brain developed in part thanks to cooking. Hulton Archive/Getty hide caption

itoggle caption Hulton Archive/Getty

Urushiol, the chemical in poison ivy, is also harvested from the Japanese lacquer tree to coat lacquerware. Here, a rash caused by lacquerware that likely was not properly cured. Kenji Kabashima hide caption

itoggle caption Kenji Kabashima