Lorenz

• Background

  • Lorenz was interested in imprinting 
  • Imprinting is an innate readiness to develop a strong bond with a mother figure
  • Many bird species imprint on the first moving object they see after hatching
• Procedure:

  • Lorenz randomly divided a clutch of gosling eggs in half
  • Half of the eggs hatched with the mother goose in their natural environment
  • The first moving object they saw was the mother goose 
  • The other half hatched in an incubator 
  • The first moving object they saw was Lorenz
  • The incubator group imprinted on Lorenz and followed him everywhere
  • The other group imprinted on the mother goose and followed her everywhere
  • To test this effect of imprinting, Lorenz marked the two groups of goslings to distinguish them and placed them together
  • Both Lorenz and the mother goose were present
• Findings:

  • The goslings quickly divided themselves up
  • The incubator group returned to Lorenz and showed no recognition of their natural mother
  • The other group returned to their mother

  Conclusion:

  • This research demonstrates the process of imprinting
  • Imprinting is a process similar to attachment
  • It binds an infant to a caregiver
• Subsequent research by Lorenz 

  • Subsequent research conducted by Lorenz focused on two factors
  • Critical period for imprinting
  • Sexual imprinting

  Critical period for imprinting

  • Lorenz identified that there is a critical period in which imprinting must take place
  • Depending upon the species, this can be as brief as a few hours after hatching
  • If imprinting does not occur within this period, it will not occur
• Sexual imprinting

  • Lorenz also investigated the relationship between imprinting and adult mate preferences
  • He observed a peacock that had been reared in the reptile house of a zoo
  • The first moving object that the peacock saw after hatching was a giant tortoise
  • As an adult, this peacock would only direct courtship behaviour towards giant tortoises
  • Lorenz therefore suggested that imprinting has a permanent effect on adult mate preferences