Parental Behaviors - imprinting

Konrad Lorenz → imprinting

“Process of a newly hatched or born animal attaching itself to some large object which appears during the critical stage of development”

• The critical stage is quite early in life

imprinting

A process by which social attachments are made early in life that will influence behavior later in life

• Filial imprinting: social attachments form between parents and offspring

• Sexual imprinting: attachment forms by which an individual learns to direct it sexual behavior at members of its own species

• A rapid learning process by which a newborn or very young animal establishes a behavior pattern of recognition and attraction towards other animals of its own kind, as well as to specific individuals of its species, such as its parents or to a substitute for these

• Survival of newborn animals

• Critical sensitive period

• Irreversible

• Individual animal's preference for a certain species

• Some behaviors are affected by imprinting more than others

• Stressful stimuli reinforce imprinting

imprinting → critical sensitive period

• Specific time: early postnatal life

• Ducks and geese: 24-48 hours after hatching, when the “following response” is learnt

robotic imprinting

a cylindrical robot to a group of 8-12-hour-old chicks, most began to follow it around the arena

Licensed breeder, Robert Labrie

Licensed breeder, Robert Labrie of Townshend, VT, owner of Friesians of Majesty FPZV-USA, imprints his foals to himself when they are born. This lessens their innate fear of people. He is working on getting his process patented

imprinting: irreversible

• It is retained for life

• Not to be forgotten or unlearned

rearing technique

to avoid chick imprinting on humans, people dress in white and feed chicks with a whooping crane puppet

imprinting → it establishes an individual animal’s preference for a certain species

Once animals have imprinted, they will always prefer to follow

the learned stimulus rather than a member of their own species

juvenile whooping cranes

follow an ultralight aircraft piloted by Brooke Pennypacker during their 2004 migration from Wisconsin to Florida

sexual imprinting

• Jackdaws

• Sexually dimorphic species: sexual imprinting varies depending on whether the youngster is male or female. Male mallard duckling will identify his future mate by relating it to the appearance of his mother or attachment figure; not for the female

• Falcons: combination of human and avian stimuli

imprinting → stressful stimuli fortify imprinting

If there is an increased level of stress at the time of the original imprinting, the learning is more robust that normal

imprinting → from the parent’s point of view

• Aids parent(s) in keeping track of precocial young

• Prompts parents to feed and nurture young (e.g., young altricial birds begging for food)

• Is there effective natural selection for a young animal having a strong instinct to imprint?

• What happens to those who do not?

some imprinting aids

– Scent

– Vocalizations

– Visual cues

– Physical contact

california sea lion

• This California sea lion mother carefully sniffs her newborn pup

• Scent will be an important means of finding the pup on the crowded birthing grounds

• Pups can swim at birth and walk reasonably well within 30 minutes

vocalizations

• Theses recently born sea lion pups practice their vocalization skills

• Each mother sea lion recognizes the distinctive call of her pup among all those in the rookery

parent-offspring bond

Scent, visual cues and physical contact are all important in the parent-offspring bond

survival strategies

• Long legs

• Camouflage, ability to freeze

• Behavioral signals associated with young (clicking in foals, submissive posture in pups, begging for food in many species)

• Importance of tactile support

potoos

highly nocturnal, generally do not fly during the day. Spend the day perched on branches with the eyes half closed. Cryptic plumage: stumps; when detect potential danger they "freeze" resembling a broken branch

jaguars coat colors

may have a spotted or black coat color. Which do you think would have a selective advantage early in life? Might the situation be different in adulthood?

• The black jaguar (Panthera onca): a rare color variant of the onca species.

• From the word yaguar the Indian term meaning, “killer which overcomes its prey in a single bound.”

• Black jaguars are unique among the big cats in their method of killing their prey: if an animal is small, they simply smack the prey’s head and break its skull; if the animal is larger, they pierce the skull with their canines.

• Jaguars have the most powerful jaws of all the big cats.

• Black jaguars: the largest big cats in Central and South America (max 250 pounds, 7 feet); excellent climbers and swimmers and can even hunt in water

• Tawny with rosettes: the most common

• Black: much more melanin but rosettes are still visible

• Albinos occur but are quite rare

black jaguars

• The black jaguar’s unique coloration: excellent camouflage in the dense rainforest.

• The color is not black but dark brown; black jaguars have “rosettes” which are only visible in bright sunlight.

• The black color: a result of surplus melanin; the melanistic trait is a gene mutation which causes the fur to be very dark brown.

The black jaguar’s melanism is considered a favorable evolutionary mutation by most scientists

zebu cows

• When Zebu cows are milked, the young must be present to stimulate milk let-down

• This is not true for more intensively selected dairy cattle like Jerseys or Holsteins

Tactile stimuli

In a series of experiments, Harry Harlow (Sci. Amer. 200, 1959) showed that baby Rhesus monkeys raised without mothers preferred a soft surrogate even if food were provided by a different (less comfortable) surrogate. When frightened or challenged, the babies always went to the surrogate that provided tactile comfort

South American Titi Monkey

• Small (1.5 to 3 lbs.) monkeys

• Small, monogamous family units

• Unusual in mammalian species because fathers contribute greatly to care of young

• Father is primary caretaker and source of emotional security

• Tail-twining is a characteristic of family members and it is often done between father and offspring (tactile stimuli)

physical contact between parent and offspring

→ Gentle physical contact between parent and offspring is important in raising individuals who can themselves then become good parents.

→ Grooming is also essential for well-being of the offspring

The importance of a well-groomed child

• Importance of neonatal handling (Levine, 1950’s)

• The handling of rat pups by humans (15 min daily, first few weeks of life) has a subsequent positive effect on the rats' endocrine system and cognitive functioning as adults.

• A report in this issue indicates that this effect may be due to the intense licking and grooming that these handled pups receive by their mothers when they are returned to the fold

a well-groomed child

• Handling and increased maternal care are confounded in these experiments: one or the other or both of them made the difference

• Experiments with chickens (Siegel, Gross) showed that handled chicks grew faster and more efficiently than unhandled ones

warthogs

→ Warthogs running: this type of social organization is a direct result of imprinting (following response)

→ Will it increase the life expectancy of the little warthogs?