Konrad Lorenz was an Austrian zoologist (1903-1989), considered to be one of the founders of modern ethology. Lorenz studied instinctive behaviour in animals, and is renowned for rediscovering the principle of imprinting in his work with geese, as well as for his work on on the roots of aggression. Lorenz shared the 1973 Nobel Prize with Nikolaas Tinbergen and Karl von Frisch.