Research with captive Komodo dragons has shown that they play. One dragon would push a shovel left and seemed attracted to the sound of it moving across rocks. A young female dragon at the National Zoo in Washington, D.C. would grab and shake things like statues, drink cans, plastic rings, and blankets. She would also put her head in boxes, shoes, and other objects. She did not make a mistake and think these objects were food; she would only swallow them if they were covered in rat blood.