Thu 12th July - Foundations of Ethology Flashcards
Early animal behaviour
Why would early humans be motivated to study animal behaviour?
- Hunting
Learn their behaviour to hunt them
- Survival
Avoiding predation/danger from sabertooth
What two factors can act on behaviour?
Natural selection
&
Artificial selection
Explain why and how genes/traits are inherited
&
What are three requirements for behaviour selection?
Nature is the selective againt
Therefore traits including behaviours that better suit an individual to their environment, and that can be inherited, the gene associated with those traits are more likely to increase/be inherited by the population over time.
- Variation in a trait (Ravens slow/fast response)
- Fitness consequences for a trait (must benefit fitness)
- Heritability (Must have genetic basis)
Key words
Trait: A distinguishing quality or characteristic
Characteristic: A feature or quality associated with a animal
Behavioiur: The way in which an animal or person behaves in response to a particular situation or stimulus.
Selection for Behaviour
Artificial selection can act on behaviour
If a raven has more confidence and quicker reactions to _____ _____ than other ravens. There may be some ______ ______.
Give an example of the above
Maybe able to provision its mate who is incubating eggs better than a slow moving raven who takes far longer to gather food so their mate is not able to produce as many eggs or successfully incubate as many so a greater or lower offspring number is affected by this variation.
1. Novel Items
2. Fitness pay off
Example:
Exploiting a novel item could turn out to be a new food source leading to an increase of the Ravnes nesting success. The Raven may be able to provision its mate who is incubating eggs bettet than a slow moving raven who takes far longer to gather food so their mate is not able to produce as many eggs or successfully incubate and nutritionally sustain as many offspring.
In short: A greater or lower number of offspring is affected by this variation.
Not all traits are heritable
-Behaviour is also influenced by ____________ _______ such as ________ & _______.
-Don’t assume all traits (behaviours) have been optimised by _______ _________.
Not all traits are heritable
- Environmental effects
- Learning & Disease
- Natural Selection
Selection pressures change over time
- Traits may become ___________ when environments and situations change.
- Traits are not always independent of each other, so not all can be optimised by natural selection.
Genes can affect more than one trait. Just because an animal performs a certain behaviour, it does not mean it has been optimised by this process.
-When considering domestic animals – remember that _______ _______ has played a role in their phenotype (observable characteristics)
- Maladaptive (unadjustable)
- Artificial selection (selective breeding)
Define
“Gene”
A unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
“Breaching for seals was in the ‘South African’ Great Whites Sharks Genes”
DO NOT STUDY ROMANES WORK
(ANIMAL INTELLIGENCE 1882)
Morgan’s Canon
“In no case may we interpret an action as the outcome of the exercise of a higher psychical faculty if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale.”
(Morgan, 1894.) What does this mean?
Explain how Morgans Canon applys to ‘Tony the dog’
• Seek simple explanations for observed behaviour.
– Only data from experiments and observations may inform theory.
– Don’t assume similarities between humans and non-human animals.
• Reduce complex hypotheses to simple terms, to get a clear understanding of causes of behaviour.
Notes: Important to seek the simple explanations for behaviour at all times, it does not mean there isnt complex things going on but we should be looking for simple explanations.
Tony the dog
- The story goes is that Tony learnt to escape and you can see this is him sticking his head through here, he lifts his head up and it lifts the latch and the gate opens, Tony escapes to the butchers for a saussage?
- Apparently, the first time he did it he happened to be observed by Morgan, Tony had put his head through because he was looking out scanning the environment and he happened to have his head through that particular part of the gate and as he moved around he bumped the latch off which opened the gate which allowed him to escape which would have been reinfocing for the dog.
- The next few times he tried, it didnt look that smooth (lots of trial and error) eventually he learned if he put his head in a certain place and moved it in a certain way the gate would open and he would get his freedom.
- At first it looks complex and it may appear he has learnt this by watching people use the latch to open the gate. When looking at it objectively and if you had the oppertunity to observe every single time he tried, the explanation would be far more simpler.
Thorndike (catman)
Trial-and-Error Learning
-Operant conditioning: Operant conditioning is a learning process through which the strength of a behavior is modified by reinforcement or punishment. It is also a procedure that is used to bring about such learning.
Studied animal learning experimentally
- Cats placed inside ‘puzzle boxes’, with food outside.
- When they triggered the mechanism to open the box, they could escape (and eat).
The above is an example of what king of learning situation?
And what behavioural measure could we take to examine learning in Thorndike’s puzzle box experiment?
- Reinforcement
- Time to escape
Escape and food was a rewarding reinfocing situation.
Thorndike’s Law of effect:
“The cat that is clawing all over the box in her impulsive struggle will probably claw the string or loop or button so as to open the door. And gradually all the other non-successful impulses will be stamped out and the particular impulse leading to the successful act will be stamped in by the resulting pleasure, until after many trials, the cat will, when put in the box, immediately claw the button or loop in a definite way.”
(Thorndike, 1911.)
This type of learning is know as _______ __________
Exaplain it.
1. Operant Conditioning < Important
- An item of behaviour that is not a response to a prior stimulus. Something which is initially spontaneous, which may reinforce or inhibit recurrence of that behaviour.
Pavlov
A physiologist, accidentally developed the first experiment on classical conditioning.
Had dogs in a harness set up.
Little vials attached to saliva glands on face
Giving dogs meat powders and other foods and noticed they salavated before given meat powder
Started encorporating sound/visual (bell/light) stimulus with presentation.
What followed?
Sound and light stimulus associated with meat powder stimulated same reflexive response as food alone.
Skinner
Most famous 20th century behaviourist.
• Placed emphasis on looking _______ a subject.
(cf. Ramones). – E.g., consequences of actions.
• Collecting data from controlled experiments.
- Outside a subject
Alot of enthesis on looking at the outside of Animals and what we can see an observe in the consequences of actions animals are subject to.
Early Studies of Ethology
von Frisch, Lorenz, Tinbergen – founders of modern ethology.
- European scientists, preferred naturalistic observations. – In animals’ natural environments (c.f. Skinner).
- Jointly awarded Nobel Prize in 1973.
• von Frisch: honeybee waggle dance.
Explain the dance
• Lorenz: importance of observations, imprinting.
• Tinbergen: experiments in natural conditions, questions.
Used for telling hive mates where most productive flowers are
Communicates location by gathering audience by climbing on siblings backs and vibrating abdomen, now she has attention she
duration of waggle = distance to flower
virbation = direction of flower in relation to sun
Dwarf Mongooses 1
Dwarf mongooses live in large social groups.
(Most carnivorous mammals solitary)
Dominant female does the most breeding
Priority access to food
Influences pack movements
Subordinates help raise dominant pair’s offspring. – This drastically improves offspring survival.
- We can take different approaches to examining why we might see behaviour like this (from Goodenough et al., 2010).
Dwarf Mongooses 1
Ultimate questions
Function: what are the benefits for dwarf mongooses living in groups?
• Vigilance – well-founded, because often preyed upon.
– Hypothesis: group living reduces predation risk.
• ‘Many eyes’ and ‘dilution effect’.
– Research findings support this.
• 50%+ of solitary mongooses are eaten.
Subordinates’ options in terms of reproduction:
– They could leave and join new pack to improve chances of reproduction, but predation risk is high.
– Remain in pack and improve social rank to gain breeding rights.
– Some subordinates (~15-25%) do breed. – Gain indirect fitness via raising related offspring.
Modal Action Patterns
Response triggered by something and once triggered it’s hard to interupt
Originally called Fixed Action Patterns (Tinbergen & Lorenz).
• An innate, stereotypical response triggered by a simple stimulus, which will be performed in its entirety once activated. – Species-specific
. • Much emphasis on these short sequences in early ethology.
Now, recognition that there can be variation in some of these patterns (between bouts/individuals), hence name change.
- Humans show evidence of some innate, instinctive/reflexive behaviours too. (Learning lecture.) – E.g., grasping.
- Note: repeated patterns of behaviour may also result from things such as animals’ living conditions.
What triggers on the onset of MAP?
Give an example.
• Sign stimuli (and releasers).
Sometimes animals react to just a small part of the environment.
• External stimuli that set off a reaction in an animal.
Termed ‘releaser’ if social cue - within the same species.
Examples
Robins
Males attack another male which enters its territory. Red breasts is the Sign stimuli. Experiments have shown males attacking red feathered dummie birds only when presented with red feathered and brown feathered dummies.
Example: three-spined sticklebacks.
• Males (red-bellies) are territorial, aggressive towards intruders. • Tinbergen experimented with the variables that might trigger aggressive responses.
Question: of these models, which do you think a male would attack the most?
Red bellie model which look most familiar.
- Give an example of an animal that exhibits begging behaviour.
- What is the benefit of being triggered by a small environmental stimulis?
- Herring gull chicks begging behaviour
Shape of bill and red dot are important are important releasers in triggering begging behaviour.
- Not wasting precious energy by responding to every single stimulus in the environment
What is and give an example of
‘Supernormal Stimuli Studies’
“A hijacking of animal instincts beyond their evolutionary purpose”
- Stronger responses from animals when presented with model with exaggerated features.
- E.g., oystercatchers preferentially incubating (or trying to) giant egg models.
Early Principles: Supernormal Stimuli Sure, not common in nature – but important to be aware of this phenomenon.
• E.g., case of leg bands put on zebra finches
– different colours (Burley et al., 1982).
• Males with red bands = more attractive to females.
• Females are normally attracted to males’ red beaks … Addition of leg bands = supernormal males. 40
• Results?
– Females made more foraging attempts.
– Survival of offspring is better than average.
