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BEHAVIOURS FOR SURVIVALChapter 11
BEHAVIOUR
Way an organism reacts to changes in its external or internal environment
Influenced by genetics and environment Asks “why” (the behaviour exists) Asks “how” (the behaviour is triggered,
controlled, performed)
BEHAVIOUR DEFINITION
Behaviour in an organism = action that occurs in response to a stimulus/stimuli
Stimulus?
Action?
Urge to mate
Build Bower
OBSERVING ANIMAL BEHAVIOUR
Konrad KorenzKarl von FrischNikolaas Tinbergen
INNATE VS LEARNED
BehaviourActivity performed in response to stimulus
Innate Learned•Genetic•Same in all individuals of spp.
•Develop/change due to experience•Trial & Error
INNATE BEHAVIOUR
Instinctive or Inborn Essentially the same in all members of a spp.
Fully functional first time performed Some improvement with performance or
maturation eg
suckling Nest building Web weaving
INNATE BEHAVIOUR
Rhythmic behaviours – repeat on a regular basis Feeding, sleeping, migration, hibernation/torpor Regulated by internal (“biological clock”) and
external factors (light cycles)
FEEDING BEHAVIOURS
Orca co-operative hunting:
http://www.youtube.com/watch?v=p3xmqbNsRSk
Humback whale bubble-netting:http://www.youtube.com/watch?v=vJvfjiCTvq4
MIGRATION
Regular, recurrent, seasonal movement of populations from one geographic location to another and back again
Response to change in temperature (winter) or reduction in food resources
Salmon migrating to spawn Wildebeest mass migration
COMMUNICATION
Transmission, reception of, and response to signals
Signals cause change in behaviour: Visual, auditory, tactile, chemical
Examples: Pheromones (ants, bees) Dance of the honey bee Bird song Feigning of an injury (killdeer ‘broken wing’
display) Visual display (stickleback fish) Begging behaviour of chicks (herring gull)
Niko Tinbergren demonstrated visual displays initiate reproduction
Red belly of the male attracts a female, who adopts a head up posture
Male makes a series of zigzag motions, leading the female to his nest
Male prods base of her tail, prompting her to deposit eggs
The male enters the nest and fertilizes the eggs
Case study: Stickleback Fish
CASE STUDY: STICKLEBACK FISH
Aspect of Communication
Particular case with Stickleback
Stimulus
Sender
Receiver to whom signal is directed
Kind of signal sent
How is signal sent
Behaviour of receiver
Setting in which communication occurs
•Signals trigger instinctive acts = releasers •Once a particular response is released it usually runs to completion, even if stimulus removed•Why? How does this aid survival?
CASE STUDY: STICKLEBACK FISH
Aspect of Communication
Particular case with Stickleback
Stimulus Desire to mate
Sender Male stickleback
Receiver to whom signal is directed
Female stickleback
Kind of signal sent Appearance of red belly
How is signal sent Visual display
Behaviour of receiver Attracted to red colouration
Setting in which communication occurs
Courtship behaviour
•Signals trigger instinctive acts = releasers •Once a particular response is released it usually runs to completion, even if stimulus removed•Why? How does this aid survival?
STICKLEBACK MALE AGGRESSION
Niko Tinbergen observed males reacted aggressively when red trunks (board-shorts) passed by their tank
STICKLEBACK MALE AGGRESSION
Behaviour = males attack other males in territory
Sign stimulus = red belly Demonstrates that
animals can be induced to respond to inappropriate releasers
Animals respond selectively to certain aspects sensory input received
CASE STUDY: WHITE-WINGED-TANAGAR-SHRIKE
Hawk Alarm call given when shrike spots a hawk – predator
Shrike also gives alarm call when it spots a competitor chasing an insect, but no hawk
Competitor responds to alarm call regardless
Why does competitor bird respond to alarm call?
SOCIAL & TERRITORIAL INTERACTIONS
Social interactions = two or more individuals Can be:
Co-operative Prey capture by lion pride Courtship of long-tailed manakin
SOCIAL & TERRITORIAL INTERACTIONS
Conflicting Territory/resource aggression Mate selection
Reproductive behaviour variation to distinguish spp. May appear morphologically similar, but
distinguishable by behaviour variation
SOCIAL & TERRITORIAL INTERACTIONS
Ravens of one spp. able to identify members of own spp. Why is this important?
SOCIAL & TERRITORIAL INTERACTIONS
Courtship behaviour eg mating dances, male song, allows both recognition and reproductive isolation.
Each of the stages of courtship depend on the behaviour of the partner.
The male will only move onto the second stage of the exhibition if the female shows certain responses in her behaviour.
He will only pass onto the third stage when she displays a second key behaviour
Prevents interbreeding and hybridisation
GROUP ORGANISATION
Animal societies may exhibit one of more of these behaviours: cooperative rearing of young by the group overlapping generations living in a permanent,
as opposed to seasonal, group cooperative foraging or hunting social learning (such as a young chimpanzee
learning by observation to use a twig to fish for termites)
BBC Life of Mammals ep 9: Social Climbers
GROUP ORGANISATION
Caste system found in eusocial animals eg ants, bees, termites
Each caste has a different structure, with a different role in the group
BBC Life in the Undergrowth ep 5: Supersocieties
LEARNED BEHAVIOUR
Acquired or modified by experienceTypes: Habituation Association
Classical Conditioning Operant Conditioning (trial and error)
Insight (reasoning) Imprinting
Habituation Learning involving loss of responsiveness to
repetitive stimuli that do not reward or harm the animal.
Allows an animal to concentrate energy on signals that are important to survival and reproduction.
Associative learning involves the linking of one kind of stimulus with another, or with a behaviour.
In general, an animal learns to associate stimuli that are relevant for survival Classical Conditioning Operant Conditioning
Conditional Learning Animal learns to associate unrelated response with
a stimulus Involuntary or innate response becomes associated
positively or negatively with a stimulus that did not originally elicit that response. Ivan Pavlov experimented with a dog's innate behaviour
of salivating. He conditioned a dog to associate the ringing of a bell with feeding (which caused salivation) so that even with the absence of food, the ringing of a bell would cause the dog to salivate.
CLASSICAL CONDITIONING
CLASSICAL CONDITIONING
Certain circumstances need to be met for classical conditioning to occur.
The conditioned stimulus must proceed unconditioned stimulus. i.e. must get bell before food.
There must be a short interval between the two stimuli – to make association
home video of conditioning behaviour
OPERANT CONDITIONING Animal learns to behave
in a certain way through repeated practice
(trial and error) involves learning to associate a behaviour with a reward or stimulus and modifying later behaviour accordingly.
B.F. Skinner in the 1930s using the "Skinner box," which rewards an animal with food when the correct coloured button or lever is pressed.
REASONING
Analyze problem & devise solution using past experiences
Occurs when an animal applies past experiences to solve new problems without a period of trial and error.
Most complicated form of learning.
IMPRINTING
Specialised type of learning limited to a critical time early in the life of an animal.
Irreversible. Konrad Lorenz - artificially incubating duck and
goose eggs observed the newly hatched goslings and ducklings. Formed a social bond with him instead of with
their mothers. The ducklings and goslings "imprinted" on him, the
first moving object they saw following hatching. Young bird does not instinctively recognize adult
members of its own species but requires this special type of learning.
IMPORTANT TO NOTE!
Instincts are not purely genetically determinedMany instincts are modified by learningEg Walking – instinctual but gets better
with practice. Learning is not purely environmentally
influenced.Genetic effects constrain what can be
learned easily. This helps you learn things that are
useful.
OBSERVATION VS INFERENCE
OBSERVATION VS INFERENCE
What you know and can verify vs what you think you know because you have concluded it.
Don’t pass off your inferences as observations!
So... You can see and verify that dolphin broke
surface; you can only infer that it took a breath.
You can see a dark fluid cloud; you can only infer that it is blood.
You can see that the mother’s head contacted the baby’s belly; you can only infer a deliberate push.
OBSERVATIONS VS INFERENCE
OBSERVATION VS INFERENCE
Seeing a large dolphin with a small dolphin does not always mean mother-baby
Treating that conclusion as an observation closes mind to other possibilities (the role of siblings? the role of fathers? etc?)
Other important elements of the scene? Was it captive- or wild-based, and how do
you know? How long did it last? Were there other individuals present, and
what did they do?
OBSERVATIONS VS INFERENCE
OBSERVATIONS VS INFERENCE
Did you assume this took place in Africa? Asiatic Lion (India) – don’t make
assumptions! Only state what you see!
OBSERVATIONS VS INFERENCE
OBSERVATIONS VS INFERENCE Recording observations
Ad lib sampling Informal, note-taking of behaviours occurring at regular time
intervals
Ethogram (ethology = study of behaviour) catalogue of an animal’s behavioural repertoire, detailing the
different forms of behaviour that are displayed by an animal Definitions should be clear, detailed and distinguishable from
each other – don’t label the behaviour
Yes – “open beak thrust...” No – “threat behaviour”Example for birds: Maintenance Self-Preening (SP): The subject is manipulating its own feathers with its beak,
stretching, or any other maintenance behaviour, including sunning Bathing (water or dust) (BA): The subject is coating its feathers with water or dust
(connote with a w or d, i.e. BAw).