Courtship Behaviour (AQA A-Level Biology): Revision Notes
Courtship Behaviour
What is courtship behaviour?
Courtship behaviour refers to the specific patterns of behaviour displayed by animals before mating. Members of the same species share similar behaviours because they have the same genes and resemble each other physically and biochemically. This behavioural similarity helps individuals distinguish members of their own species from those of other species.
The ability to display specific behaviours is genetically determined and has evolved over time. These behaviours directly influence the survival chances of a species, making courtship and mating processes essential for species continuation.
Courtship behaviours are inherited traits that have been shaped by evolution. Animals don't learn these behaviours - they are born with the genetic programming to perform species-specific courtship rituals.
Why is courtship behaviour important?
Since no individual lives forever, reproduction serves as the primary mechanism for species survival across generations. Each individual possesses adaptations that help ensure their DNA passes to the next generation through successful reproduction.
Female animals typically produce eggs only at specific times, often just once yearly. Therefore, successful mating with maximum offspring survival chances becomes vital for species continuation.
Without effective courtship behaviour, species would fail to reproduce successfully and face extinction. The timing and precision of these behaviours are critical for species survival.
Functions of courtship behaviour
Courtship behaviour enables individuals to accomplish five key objectives:
1. Recognise members of their own species
This ensures mating occurs only between members of the same species, as only same-species partnerships can produce fertile offspring.
2. Identify a mate capable of breeding
Both partners must be sexually mature, fertile, and receptive to mating for successful reproduction.
3. Form a pair bond
Creating a strong connection between partners leads to successful mating and effective offspring care.
4. Synchronise mating
Timing mating to coincide with maximum sperm and egg viability increases fertilisation probability.
5. Become able to breed
Bringing a potential partner into a physiological state that allows breeding to occur naturally.
These five functions work together as a comprehensive system. If any one function fails, the entire courtship process may be unsuccessful, preventing reproduction from occurring.
Communication through courtship signals
During courtship, animals use signals to communicate with potential mates and members of their own sex. A typical chain of actions occurs between male and female animals. Although this behavioural sequence remains consistent for all members of a species, it differs between different species.
This species-specific behaviour pattern allows both individuals to recognise their partner belongs to the same species and may be prepared to mate.
Communication Example: Bird Courtship
Step 1: Male bird performs a specific song or call
Step 2: If the female is of the same species, she responds with a particular behaviour
Step 3: Male escalates with visual displays (dancing, feather display)
Step 4: Female either accepts (stays and responds) or rejects (flies away)
Step 5: If accepted, the pair proceeds to mating behaviour
Timing and sexual cycles
Females of many species experience cycles of sexual activity, during which they can conceive only during very short periods. They become receptive to mating primarily around the time when they produce eggs.
Males use courtship behaviour to determine whether females have reached the receptive stage. If females respond with appropriate behavioural responses, courtship continues and likely results in offspring production. If females are not receptive, they display different behaviour patterns, causing males to cease courting and redirect their attention elsewhere.
The timing of courtship is crucial. Males must be able to accurately detect when females are in their fertile period, as mating outside this window will not result in successful reproduction.
Key Points to Remember:
- Courtship behaviour is genetically determined and species-specific, helping animals recognise suitable mates
- The five main functions ensure species recognition, mate selection, pair bonding, timing synchronisation, and breeding readiness
- Signal communication occurs through chains of actions that are unique to each species
- Female sexual cycles determine receptive periods, which males detect through courtship displays
- Successful courtship leads to reproduction and species survival across generations