26.2:
Imprinting
Imprinting is the process by which some newborn animals and parents recognize each other and form a long-term bond. For example, mother sheep imprint onto their lambs during a critical period, within hours of birth, allowing them to identify and care for their own offspring within a large herd. Imprinting is always restricted to a brief critical period, shortly after birth or hatching.
For instance, in geese, goslings imprint onto their mother within their first day of life. Thereafter they will follow her whenever she moves.
If the mother is removed before hatching, goslings will imprint onto the first large moving object they're exposed to during their first day, even a person. Afterwards, they will always follow this imprinting stimulus and will ignore their biological mother.
Therefore, although the instinct to imprint is innate, the specific object of imprinting is a learned behavior based on exposure during the critical period. Imprinting is irreversible. Once the critical period ends, the object of imprinting can't be changed. Also, if there is no appropriate stimulus during this time window, the animal will not imprint at all.
By creating a strong long-lived bond, imprinting allows parents to care for and teach their offspring, increasing their chances of survival.
26.2:
Imprinting
Behavioral imprinting is observed in some newborn animals and occurs when they develop strong and specific attachments to another animal (usually a parent) following brief, early-life exposures. Offspring imprint onto parents within a brief period after birth or hatching; this time window is called the critical period. Once imprinting occurs, the bond established between the parents and their offspring is usually long-lasting.
Survival
Mother sheep imprint onto the scent of their lambs within a few hours after their birth. Since many females in the herd give birth at the same time of year, imprinting allows the mothers to selectively recognize and care for their lambs.
Imprinting also occurs in the opposite direction, with offspring imprinting onto their parents. This is particularly common in waterfowl, such as goslings (baby geese), which imprint onto their mother on the first day after hatching. Afterward, they follow the mother wherever she goes. This behavior allows the mother to protect her offspring and teach them the skills they need to survive.
Classic Work
In the 1930s, Konrad Lorenz showed that goslings imprint onto the first large, moving object they see during the critical period. In the absence of their mother, this object could be siblings, a person, or even an inanimate object. After that, they will always follow this substitute “mother,” called the imprinting stimulus, even when presented with their biological mother or other adult geese.
These experiments showed that the stimuli present in the environment determine the object of imprinting during the critical period. Therefore, imprinting results from a combination of the instinctive behavior to imprint and learning based on experience.
Imprinting occurs only within the critical period and cannot be changed after the critical period ends. This is why goslings that have imprinted onto a human will continue to follow the human later in life, even when exposed to their mother. If there is no appropriate imprinting stimulus during the critical period, the young animals will never imprint at all.
Suggested Reading
Ueda, Hiroshi, Shingo Nakamura, Taro Nakamura, Kaoru Inada, Takashi Okubo, Naohiro Furukawa, Reiichi Murakami, et al. “Involvement of Hormones in Olfactory Imprinting and Homing in Chum Salmon.” Scientific Reports 6 (February 16, 2016): 21102. [Source]
Mobbs, Elsie J., George A. Mobbs, and Anthony E. D. Mobbs. “Imprinting, Latchment and Displacement: A Mini Review of Early Instinctual Behaviour in Newborn Infants Influencing Breastfeeding Success.” Acta Paediatrica 105, no. 1 (2016): 24–30. [Source]