Imprinting and critical periods
Konrad Lorenz found that newly hatched greylag goslings followed the first moving object they saw—Lorenz himself—as if it were their mother. This imprinting happens only during a brief critical period and is hard to reverse. Niko Tinbergen studied fixed action patterns triggered by sign stimuli; both shared the 1973 Nobel Prize in Physiology or Medicine.
Applying it to humans
John Bowlby argued that infants' crying, smiling, and clinging evolved to keep caregivers close, forming attachment early in life. For humans, the more flexible idea of a sensitive period—as in language learning—fits better than a strict critical period. The theory champions naturalistic observation but is criticized for underplaying culture and learning and for generalizing from animals. It echoes classic instinct theory but rests on empirical observation.
FAQ
- Critical vs. sensitive period?
- A critical period is a window after which development is nearly impossible; a sensitive period is when it's easiest but still possible later.
- What research method does ethology favor?
- Naturalistic observation of behavior in real environments.
Sources reviewed: 2026-10-26
References
- Lorenz, K. (1935). Der Kumpan in der Umwelt des Vogels. Journal für Ornithologie, 83, 137–213.
- Tinbergen, N. (1951). The Study of Instinct. Oxford: Clarendon Press.
- Bowlby, J. (1969). Attachment and Loss: Vol. 1. Attachment. New York: Basic Books.
- Hess, E. H. (1959). Imprinting. Science, 130(3368), 133–141.