{"fact":"While kids easily kept track of rewards on a rotating tray, whether visible or hidden, New Caledonian crows had a tougher time when rewards were hidden, likely because they don't typically follow human hand movements.","context":"In Experiment 2, 5-year-old children outperformed 3- and 4-year olds, though overall children still performed well, while the crows struggled when reward visibility was manipulated, a result which may relate to difficulties in tracking the experimenters’ hands during baiting.","source":"Rachael Miller; Anna Frohnwieser; Martina Schiestl; Dakota E. McCoy; Russell D. Gray; Alex H. Taylor; Nicola S. Clayton, Delayed gratification in New Caledonian crows and young children: influence of reward type and visibility, 10.1007/s10071-019-01317-7","index":324}