Observational learning
Learning from peers is called horizontal social learning, learning from parents is called vertical social learning. Horizontal social learning is consistent with the lone crows that recognized the dangerous face without ever being captured. Children of captured crow parents were conditioned to scold the dangerous mask, which demonstrates earning from parents. The crows that were captured directly had the most precise discrimination between dangerous and neutral masks than the crows that learned from the experience of their peers. The ability of crows to learn doubled the frequency of scolding, which spread at least 1.2  km from where the experiment started to over a 5-year period at one site.