re Stone-curlews at MF

[Philip Veerman <>]

In response to Chris.  I don’t think that is right. Yes Imprinting occurs at an early stage of development and allows young to be attached to their parents. In most cases obviously the thing they imprint to is a parent. Thus as young chicks they will usually learn to “follow their mum” and later when they grow up court something similar. However when it is done wrong, it does typically leads them to want to mate with the wrong species. Certainly with people or other birds but I don’t know about wanting to mate with flags. Usually the thing they imprint on needs to be moving and for some species making a noise of the right general type. ......... Also the sexes will differ as to the effect. Obviously I don’t know about all species and of course there is a range of reactions but generally females are more likely to know how to recognise proper mates later in life (regardless of imprinting), whereas males are more likely to retain the wrong imprinting into adulthood. So imprinted males are more likely to have the wrong sexual response than imprinted females.

 

A couple links.........

 

Konrad Lorenz, (born Nov. 7, 1903, Vienna, Austria—died Feb. 27, 1989, Altenburg), Austrian zoologist, founder of modern ethology, the study of animal behaviour by means of comparative zoological methods. His ideas contributed to an understanding of how behavioral patterns may be traced to an evolutionary past, and he was also known for his work on the roots of aggression. He shared the Nobel Prize for Physiology or Medicine in 1973 with the animal behaviourists Karl von Frisch and Nikolaas Tinbergen.

Lorenz was the son of an orthopedic surgeon. He showed an interest in animals at an early age, and he kept animals of various species—fish, birds, monkeys, dogs, cats, and rabbits—many of which he brought home from his boyhood excursions. While still young, he provided nursing care for sick animals from the nearby Schönbrunner Zoo. He also kept detailed records of bird behaviour in the form of diaries.

In 1922, after graduating from secondary school, he followed his father’s wishes that he study medicine and spent two semesters at Columbia University, in New York City. He then returned to Vienna to study.

During his medical studies Lorenz continued to make detailed observations of animal behaviour; a diary about a jackdaw that he kept was published in 1927 in the prestigious Journal für Ornithologie.He received an M.D. degree at the University of Vienna in 1928 and was awarded a Ph.D. in zoology in 1933. Encouraged by the positive response to his scientific work, Lorenz established colonies of birds, such as the jackdaw and greylag goose, published a series of research papers on his observations of them, and soon gained an international reputation.

In 1935 Lorenz described learning behaviour in young ducklings and goslings. He observed that at a certain critical stage soon after hatching, they learn to follow real or foster parents. The process, which is called imprinting, involves visual and auditory stimuli from the parent object; these elicit a following response in the young that affects their subsequent adult behaviour. Lorenz demonstrated the phenomenon by appearing before newly hatched mallard ducklings and imitating a mother duck’s quacking sounds, upon which the young birds regarded him as their mother and followed him accordingly.

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Lorenz’s early scientific contributions dealt with the nature of instinctive behavioral acts, particularly how such acts come about and the source of nervous energy for their performance. He also investigated how behaviour may result from two or more basic drives that are activated simultaneously in an animal. Working with Nikolaas Tinbergen of the Netherlands, Lorenz showed that different forms of behaviour are harmonized in a single action sequence.

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And

 

The first thing a certain brood of baby geese saw when they hatched was Conrad Lorenz, one of the first great behavioral theorists. As young geese, they followed him everywhere he went and became sexually attracted to him as adults. The baby geese had imprinted on Lorenz. In the process of filial imprinting, the imprinting of offspring on their parents, there is a critical period for learning that is irreversible once something has been imprinted upon. The hatchling geese imprinted on Conrad Lorenz, and nothing could de-imprint them. Ducklings have also been known to imprint on people. Both ducks and geese are precocial birds. Unlike altricial birds, which are helpless for several weeks after hatching, precocial birds quickly start walking around. They need to follow something for their own safety and thus imprinting is vital to their early survival.

The concept of a critical period for learning is not restricted to imprinting, nor to geese. Songbirds have a critical period for song learning, as we will see in Signaling and Communication. Humans also seem to have a critical learning period. In children age 4 years and younger, learning a language is almost effortless. No class is needed, no specific instruction; they pick it up on their own. After age 13, it is much more difficult to learn a language. For older people, it is virtually impossible to learn to speak as well as a native.

Neural Control of Filial Imprinting

Johnson and Bolhuis identified two independent neural systems that control filial imprinting in precocial birds. Newly hatched chicks will follow almost anything that has eyes and moves. After the chick follows something, another part of the brain, analogous to the frontal cortex, recognizes and imprints on the individual being followed. These mechanisms are independent. There is an instinct for chicks to follow, and then they learn what they are following.

It might seem odd that being able to identify and follow a mother does not have a genetic mechanism. Yet with a neural rather than genetic mechanism, the chick gains flexibility that might help in survival. If a chick's mother dies, the chick can then be adopted by another family member or conspecific. If the chick's recognition of its mother were genetic, the chick would not follow its adoptive parent, and would die. Further, detailing the recognition of a specific individual is far too complicated to achieve genetically. An individual may be able to tell what relationship he has with others, but cannot be genetically programmed to recognize a certain individual, particularly because environment plays a large part in appearance. The chick's neural imprinting system allows more adaptive flexibility and hence is an advantage.

Sexual Imprinting

Most animals are not monogamous. In many species, males mate and leave, while the female raises the offspring. Many animals receive no parental care at all. If a young female is raised by her mother, with no father around, how can she learn to recognize potential future mates? Females learn to recognize what an appropriate mate should look like from their siblings or neighbors. Sexual imprinting is a general imprinting; it is not specific to individuals, only species typical characteristics. If a female were to imprint specifically on his sister, or vice versa, inbreeding would result, which reduces a population's fitness. The more general system of sexual imprinting allows young to learn to recognize potential mates without inbreeding.

There are many examples of offspring raised by foster parents of a different species preferring to mate with the foster species over its own species. Lorenz's geese were more sexually attracted to humans than to other geese. Goats raised by sheep mature and prefer to mate with sheep, and sheep raised by goats prefer to have goats as mates.

 

 

 

From: Chris Davey [
Sent: Tuesday, 5 April 2016 9:03 PM
To:
Subject: [canberrabirds] re Stone-curlews at MF

 

Hi,

 

Curlews at Mulligans again!.

 

In my email of 4^th April I was not referring to imprinting. That is another issue. Imprinting occurs at an early stage of development and allows young to be attached to their parents.

Imprinting is not for life and does not mean that young raised with foster parents will only subsequently mate with the foster species. In most cases birds will, as adults, mate with their own species.

 

Chris