Japanese quail protect their offspring from predators with a form of customized camouflage. George Lovell, of Scotland’s University of St. Andrews, and colleagues realized that while quail eggs come in many patterns and colors, those from the same female quail tend to look quite similar. “You could almost tell which quail had laid particular eggs,” says Lovell. They tested the birds’ camouflaging skills in the lab by giving them the option of laying eggs on white, yellow, red, or black sand. The birds concealed their eggs in two different ways. When more than 30 percent of an egg was covered in splotches, the quail laid it on sand that matched the spots, making it difficult for potential predators to discern its edges—the same principle that makes army camouflage effective and allows moths to blend in with trees. Birds with relatively unspotted eggs, meanwhile, laid them on the sand that best matched the background colors. Lovell says the disguise may be important for quail...