1. Internal stimuli: These are internal factors that motivate the animal to behave in a certain way. For example, hunger may stimulate an animal to search for food, while thirst may stimulate it to seek out water.
2. External stimuli: These are external factors that can trigger a behavioural response in an animal. For example, the sound of a predator may stimulate an animal to flee, while the sight of a potential mate may stimulate it to approach.
3. Learning: Animals can learn through experience to associate certain stimuli with certain behaviours. For example, an animal that has been rewarded for performing a certain behaviour may be more likely to perform that behaviour in the future.
4. Genetics: Some behaviours are inherited, meaning that they are passed down from parents to offspring. For example, some animals are naturally more aggressive than others, while some are naturally more shy.
5. Social interaction: Animals can be influenced by the behaviours of other animals. For example, an animal that lives in a group may be more likely to exhibit social behaviours, such as cooperation and communication, than an animal that lives alone.