Evolution, genes, environment and behaviour

Alleles

alternative forms of a gene that produce different characteristics

Genotype

the specific and complete genetic make-up of an individual

Phenotype

the individuals overt, observable characteristics 

Chromosomes

single or double-stranded and tightly coiled molecules of DNA and proteins

Behaviourism (1930s-1950s)

assumed that there are laws of learning that apply to virtually all organisms 

• Organism is initially a tabula rasa/ “blank slate” on which experiences are written 

Ethology (study is animal behaviour)

focused on the evolutionary differences between species 

• Inherited behavioural adaptations: traits organisms are born with that help promote chances of survival / reproductive success 

Behavioural Genetics

• The study of how heredity and environmental factors influence psychological characteristics 

• It tries to explain why people differ. 

• There are a number of different methods used. 

• Two key concepts are the degree of relatedness and concordance / co-occurrence          

Heritability (0-1.00)

statistical estimates of the extent to which the variation (or differences) in a specific phenotypic characteristic within a group of people can be attributed to their differing genes

Reaction range

the range of possibilities (upper and lower limits) that a genetic code allows 

-> environment determines where the individual falls within these (genetic) boundaries 

Reciprocal altruism

behaviour in organism that reduces its fitness to survive/ reproduce while increasing another organism’s fitness