Evolutionary explanations often focus on innate and adaptive behaviour in animals and humans. Innate means “inborn”, so innate behaviour is behaviour which is present from birth. Adaptive means the extent to which a behaviour increases the survival and therefore, reproductive potential of an individual.

  • There are two main evolutionary theories, Imprinting and John Bowlby’s theory.


The tendency for the young of some bird species to follow and attach to the first large moving object they see after hatching.

Research Support – Konrad Lorenz (1935)

  • He divided goose eggs into two groups and marked each goose once hatched so he knew which geese were in which group.
  • One group was hatched with the mother goose and one group was hatched with Lorenz.
  • The geese that were hatched with Lorenz followed him and attached to him as if he were their mother and showed distress if they lost sight of him, none of the geese in this group became attached to their real mother goose.


  • Strength – the geese had an innate predisposition to establish a bond. This was an adaptive behaviour evolved over millions of years as a means of promoting the survival of the young.
  • Strength – criticises the behaviourist explanation – shows that attachment is not a by-product of food in the following ways:
  • Geese are pre-cocial animals which means they feed and look after themselves shortly after birth.
  • Imprinting occurs without any food or care being offered.
  • Imprinting is a rapid process because attachment is is the primary drive of young animals.
  • Weakness – the research was done on animals so it is debatable how far the findings can be generalised to humans.

John Bowlby’s Evolutionary Theory 

1) Adaptive Behaviour – infants have an innate desire to attach to their mothers as it increases their chances of survival.

  • If a mother does not care for her child, the child will die and therefore the mother’s genes will also die. Due to this process, mothers now have a gene for looking after their babies.

2) Monotropy – infants have an innate tendancy to attach to one figure. This attachment will be qualitatively different to any other attachment the child will make.

3) Internal Working Model – if a mother is sensitive and responds to her childs needs, the child will feel worthy of that attention and develop a sense of worth.

  • However, if a mother is insensitive and unresponsive then the child will feel worthless and will believe they do not deserve attention.

4) Critical Period – if an attachment is not made between 0-3 years from birth then the child will never form an attachment with anyone.

Research Support – Hazen & Shaver (1987)

  • Children who had sensitive and responsive mothers went on to form healthy romantic relationships in later life.
  • Children who had insensitive and unresponsive mothers went on to have problems (such as a lack of trust in their partner or being fearful about making a commitment) in their romantic relationships in later life.

Do Bella and Edward have a "healthy" romantic relationship?


  • Strengthresearch evidence by Hazen & Shaver supports Bowlby’s theory.
  • Weakness – however, the theory does not account for some people who have a poor relationship with their mother but go on to form healthy romantic relationships in later life.
  • Weakness – the theory ignores the temperament and personality of the child.
  • Weakness – the critical period is more likely to be a sensitive period. This is where attachment is most likely to occur between the ages of 0 and 3 but it can still occur after this period.
  • Weakness – the idea of monotropy is not supported by other psychologists and is considered naive as they believe people can form multiple attachments at a young age.
  • Weakness – evolutionary theory is retrospective rather than scientific because it looks at behaviours we have now and assumes that they have been caused by evolution.
  • Strength – Bowlby was the first person to look at the care of children in order to try and improve it.


Note - Make sure you understand both evolutionary theories and can give evaluation points for both because there could be a 12 mark question on either one of the theory in the exam or a question asking you to talk about both theories (in which case you wouldn’t need to go into as much depth about each theory).