Evolution, Genes, Environment & Behaviour Flashcards
What is evolution?
A gradual change over time in organic life from one form to another
What is natural selection?
The idea that characteristics that increase the likelihood of survival and reproduction will be more likely to be preserved in the population, therefore becoming more common in the species over time
What are mutations?
Random events in gene reproduction during cell division
They give rise to adaptations
What are adaptations?
Physical or behavioural changes that allow organises to meet recurring environmental challenges to their survival, thereby increasing their reproductive ability
What is biological inheritance?
How traits and tendencies are transmitted from one generation to the next
What are alleles?
Alternative forms of a gene that produce different characteristics
What does it mean if an allele is dominant?
The characteristic that it controls will always be displayed in the phenotype
What does it mean if an allele is recessive?
The characteristic that it controls will only be displayed in the phenotype if both copies of the recessive allele are passed down
What is a genotype?
The specific and complete genetic makeup of an individual
What is a phenotype?
The individual’s overt observable characteristics
Why can identical twins display different characteristics?
They share the same genotype but they have different interactions with the environment, causing their phenotypes to differ
What are genes?
Functional segments of DNA that code for proteins
What are chromosomes?
Single or double-stranded, tightly-coiled molecules of DNA and proteins
There are 46 of them in all body cells, other than sex cells (23) and red blood cells (0)
What is monogenic transmission?
When one gene pair contributes to one phenotypic trait
What is polygenic transmission?
When multiple gene pairs contribute to one phenotypic trait
What is ethology?
The study of animal behaviour
It is focused on the evolutionary differences between species
What are inherited behavioural characteristics?
Traits organisms are born with that help promote the chances of survival and reproductive success
Give an example of an inherited behavioural characteristic
A fixed action pattern - an unlearned behaviour that is automatically triggered by a particular stimulus
What is behavioural genetics?
The study of how heredity and environmental factors influence psychological characteristics
What is the degree of relatedness?
The number of genes we share with others by direct common descent
What is the concordance rate?
A statistical expression of the probability that two individuals with shared genes will share a particular trait to the same degree
What is a shared environment?
An environment in which its members experience many common features
What is a non-shared environment?
An environment in which its members experience different features
How are adoption studies conducted?
Adopted people are compared to both their biological and adopted parents
If a trait is inherited genetically then you would expect to see it present in the biological parents and not the adoptive parents
How are twin studies conducted?
Trait similarities are compared between monozygotic and dizygotic twins
If a trait is inherited genetically then you would expect the concordance rate for monozygotic twins to be higher than for dizygotic twins
Studies where monozygotic twins are raised apart are even better - they provide stronger evidence that the concordance is not due to the environment
What is heritability?
A statistical estimate of the extent to which the variation in a specific phenotypic characteristic within a group of people can be attributed to their differing genes
What is the reaction range?
The range of possibilities that a genetic code allows for
What determines where in the reaction range an individual’s phenotype lies?
The environment
What is evolutionary psychology?
Seeks to explain how evolution shaped modern human behaviour by considering species characteristics more generally
It is interested in the genetic commonalities between people
Give two behaviours posed by evolutionary psychology in which genetic fitness does not necessarily refer to the strongest or fastest individual
Kin selection
Reciprocal altruism
What is kin selection?
The evolutionary strategy in which behaviours are selected that favour the reproductive success of an organism’s relatives even if at cost to the organism itself
What is reciprocal altruism?
The behaviour in an organism that reduces its fitness to survive and reproduce while increasing another organism’s fitness, with the expectation that this favour will later be returned
Give some culturally universal characteristics
Infants are born with the ability to acquire any language
New-borns are able to perceive specific stimuli without any experience of them (e.g. facial expressions)
Basic emotions are universally recognised
