Biological basis of social behaviour: we are born 'prewired' or predisposed to behave
Evolutionary theory 1: Natural Selection -well equipped to cope with environmental challenges
to survival. Genetic environment: biological structure we receive for this purpose. Different
species have different genetic makeups according to their environmental needs.
1. The most fit species to meet environmental challenges are the ones that will
ultimately survive. The most adaptive characteritics within species will prevail thus
strengthening own species in the long run through reproduction of the fittest. Ex/weak ones
not able to secure a partner will have low reproduction success so genetic pool will be
geared to having stronger children because stronger males survive. Today is high
intelligence so greater likliehood at graduating and making money so will be healthier and
live better off.
• extension of evolutionary theory to social behaviour.
• An attempt to organize the facts about the adaptive significance of social behaviour in
animals and in human beings. Ex/behaviour-cognitive traits, attitudes not physical traits.
Psychological traits involved in social behaviour and their adaptive skills necessary for
• The systematic study of the biological basis of all forms of social behaviour, including
sexual and parental behaviour in all kinds of organisms including humans. Otherwise
humanity would not survive. People are predisposed this way.
• Behaviour is dominated by a gentically based urge to produce the mazimum numbers of
successful offspring, either directly or by favouring one's next of kin. Only will occur if we
are really motivated, out of our control, genetically based motivation to reproduce. Genetic
structure is there to ensure that is going to happen.
Three aspects of evolutionary theory
• Evolution concepts apply as much to behaviour as to structural characteristics. If have
asperger's syndrom and intelligence innormal range but low communication skills, will
have a hard time keeping a job, and relating to people around them, will not get married. If
don’t have these social skills then will 'fail' because do not have opportunity to pass on
• The adaptation of a species is always to a particular kind of environment (ecological
niche). Ex/human in different parts of the world, they will not survive in other parts of the
world ie/blackouts ran to hotels.
• Arigid dinstinction between what is innate and what is acquired is meaningless ain this
account. Nature vs nurture controversy. We are biologically fit to speak, unlike other
species, will be exposed then can occur.
How are organisms predisposed for social behaviour?
• Fixed action patterns- simple stereotyped actions that are activated by certain quite
specific stimuli. These are prewired0part of an individuals' genetic endowment and are
usually functional early in life otherwise will not survive. If child has to be taught
everything in the mean time they may not survive/ ex/breathing will know how to otherwise not survive. Other species fish know how to swim. These are different from
reflexes because they can be modifies by environment. The knee jerk reflex if do enough
time, then leg will become habituated and not jerk so temporally habituate.
The reaction to reflex gradually changes and becomes adaptive.
• Each species has its own fixed action patterns necessary for survival based upon
food (rooting response)-when mouth touched baby moves head from side to side
to find the breast.
o Smiling-enhances attractiveness of infant and ensures further attention leading to
whole chain of interactions.
o Crying-built in social signaling device. Complex response; timing determines
message and could thus convey different information
• Smiling and crying are not reflexes because they are not habituated. They
gradually change and modify. When one month cries it is not deliberate but
when 4 or 5 years, it is deliberate so mom can come. So gradually see crying is
acceptable to learning, associative learning looks at stimuli and consequences-
actions and reactions-so cries in a purposeful way. Different types of crying
means different things. Smiling is spontaneous and not that reactive. Child
smiles from time to time and triggers parents smile then becomes a social smile.
Characteristics we inherit through genetic transmission consist of:
• Features common to species-ex/nose, eyes. If any different then sex differences but all are
• Features that distinguish us as individuals ie/eye colour, skin colour, thin, heavy
o Psychological differences-can all speak, different levels of intelligences, different
• Developmental process common to species- blueprint that unfolds in a particular order
for all of us. Ie/grow before puberty.
• Variation in this process that distinguishes us as individuals. Ie/puberty starts around
same age, very few early and later year but has variation.
Method: map out genes, measure psychological traits. Manipulate genes.Animal breeding.
Behavioural genetics (50 years old)
• Assessment of relative contribution of heredity and environment to differences among
• No attempt to determine general rules regarding the degree to which a specific
psychological feature is inherited.
• Variation in heritable features is influenced by genetic differences. They are correlation
studies between genetic differences and using to predict psychological traits.
• Comparison between the extent of genetic and environmental influences
• Assessment of psychological features for people with various degrees of genetic