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).