We have long known that ravens are no birdbrains. They have been spotted caching food for later, gathering string to pull up hanging food and even trying to deceive one another. A studypublished today in Science adds an especially impressive twist: Ravens can plan for future needs that they never encounter in nature, suggesting intelligence may arise predictably from conditions that occurred multiple times across the tree of life.
The new study was led by Mathias Osvath, a cognitive zoologist at Lund University in Sweden, and graduate student Can Kabadayi. The pair replicated a series of experiments previously used to test apes’ planning abilities, this time using ravens. The ravens were first taught to use a stone to knock a food pellet out of a puzzle box. The next day, without the box present, the birds were offered a choice between the stone tool and “distracter” objects—toys too light or bulky to use as tools. The box would then be brought back 15 minutes after the selection. Despite the delay, the ravens chose the correct tool nearly 80 percent of the time, and successfully used the tools they selected 86 percent of the time