Imprinting is a phenomenon in which a young animal learns to recognize and attach to a particular object, usually its mother. Lorenz's experiments with geese showed that goslings would imprint on the first moving object they saw after hatching, even if it was not a goose. This showed that imprinting was not a genetically predetermined behavior, but rather a learned response.
Lorenz's work on imprinting has had a profound impact on our understanding of animal behavior and development. It has also helped to explain some of the ways in which humans learn and develop.