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In this topic of IBDP Biology, we will learn about Courtship Behaviour.
Courtship Behaviour
- Courtship is a pattern of behaviour used to attract a mate.
- It is a necessary precursor to successful mating.
- It is important for:
- Species recognition;
- Only members of the same species mate.
- Results in the production of fertile offspring
- Pair bond formation:
- For successful mating.
- Male and female of same species recognise each other as individuals and act in coordinated way.
- Prolonged pari bonds assist in the raising of offspring.
- This can be tempororay for one breeding season, or in some cases for life.
- Synchronisation of breeding behaviour:
- In most species, females only ovulate at specific times.
- Signals indicate that she is entering oestrus.
- Often the male will signal specific behavior to entice the female to mate.
- The female will then signal that she is receptive.
- Successful recognition of signals by both sexes increases the chances of fertilization.
- Innate releaser mechanisms – filter out stimuli, which are irrelevant from those, which will produce the correct behavioural response.
- Species recognition;
Types of behaviour
- Sign stimuli:
- Structural or colourfeul features:
- Peacocks tails
- Robin’s red breast.
- Structural or colourfeul features:
- Territorial behaviour:
- When it comes to IBDP Biology, the male defends a territory which contains fertile females.
- This ensures that he gets to mate most.
- Construction of a nest or building a structural enticer:
- Bower birds
- Sticklebacks
- Courtship dances:
- Sticklebacks
- Peacocks
- Pigeon
- Pheromones:
- Chemical substances which smell.
- Indicate sexual maturity
- Attract mates and mark territories.
- Volatile and disperse well
- Trigger courtship
- Advantages – recipient does not need to be in direct visual contact, operate in darkness, have effect for a long time and needed only in very low concentrations.
Sexual selection
- When it comes to IBDP Biology, signals are species specific.
- Courtship becomes ritualised into a series of stereotyped behaviours.
- Some individuals may show slight variations that increase his chance of mating.
- This variation is passed on to future offspring.
- Displays become more prolonged or elaborate.
That's the end of this topic.
