{"fact":"Even though they struggle, young crows keep trying to use tools, spending a lot of time practicing without immediate success.  Luckily, parents often share food, which might encourage this persistence.","context":"Juveniles’ persistence at unsuccessful tool use might be an important factor in enabling animals to acquire complex behaviours. […] Unrewarded persistence with tool use has also been observed in other animals.","source":"Jennifer C. Holzhaider; Gavin R. Hunt; Russell D. Gray, The development of pandanus tool manufacture in wild New Caledonian crows, 10.1163/000579510x12629536366284","index":467}