courtship/mating

• Biological rhythms

  • Endogenous rhythms are controlled internally and have nervous and hormonal components.
  • Exogenous rhythms are controlled by external environmental factors such as photo-periods and lunar cycles.
• territorial behaviour 


  Animals defend there territory by displays such as threats display and postures.

  scent mark the boundaries of their territories

  Weaker individuals may be pushed to the outer region
• Secondary sexual characteristic changes during courtship

  1.Rising levels of reproductive hormones and the maturation of the gonads.

  2. Colouration changes, as in the development of a red belly in male sticklebacks.

  3. Increase in size of parts of the body, as in the plumage of birds of paradise.

  4. Mating calls, as shown by nightingales.

  5. Postural displays, as in grebes shown opposite

  6. The use of chemical sex attractants, as in butterflies and moths.
• importance of courtship behaviour

  • Recognise members of their own species.
  • Recognise opposite gender
  • Identify a mate who is capable of breeding
  • Form a pair bond that will lead to successful mating and raising of offspring.
  • Synchronise mating so that it takes place when there is maximum probability of the sperm and egg meeting.
• What is a pheromone

  Organisms release chemicals that cause specific reactions in others of their species, especially during courtship and mating
• Pheromone use

  Examples: Civetone from civet cats, muscone from musk deer. Bombykol from female moths

  • Function: Play a role in courtship and mating.
  • Detection: Males of the species detect pheromones, often undetectable by humans.
  • Examples: Mares and cows release pheromones when in heat.
• Courtship conflict behaviour

  • Courtship in some species involves conflict behavior.
  • Solitary species may experience courtship conflict due to changing hormone levels.
  • Significance: Tightening pair bond and synchronizing gonad development.
  • Example: In certain spiders like wolf spiders, conflict between male and female diminishes only during copulation, ending with the female killing the male.
• courtship + mating behaviour of three spines stickleback

  • Courtship and mating behavior in three-spined sticklebacks involve various internal and external cues.
  • These cues trigger changes in secondary sexual characteristics and territorial behavior.
  • The male stickleback constructs a nest.
  • When a suitable female appears, the male performs a zigzag dance.
  • If the female responds, he leads her to inspect the nest.
  • The courtship ritual involves innate releasers and appropriate responses from both male and female.