Lecture 4 - The Four Questions Applied to Behavioural Ecology Flashcards
What two groups do species fall in to?
Specialists and generalists
Generalists example
Foxes rummaging in bins - can eat a wide range of food and line in a wide range of habitats
Specialists example
Giant panders
- Evolved to be specialised in what they eat and where they live
What volume of food do animals eat?
- A selector of specific parts of a food that chooses for highly nutritious content (giraffe)
- A bulk feeder that goes for quantity rather that quality (elephants)
How do animals choose food by colour?
- Red and black (common colours) fruit are highly conspicuous, but colour DOES NOT indicate nutritional content.
- Less common fruit colours indicate nutritional content
(tannins, proteins, carbohydrates)
How to animals choose what not to eat?
Animals will avoid foods that induce sickness (e.g. Garcia et al., 1974).
How to generalists choose what not to eat?
Generalists that may encounter many different food types pay attention to sickness inducing cues.
How to specialists choose what not to eat?
Specialists that only ever each one type of food have no facultative response.
What is the optimal foraging theory?
Finding a trade off when optimum = max energy intake / cost
larger items -> more energy available however more cost in time and energy to find and/ or process
What are the two defences prey use?
Primary and secondary
What is a secondary defence?
Reducing the likelihood of a successful attack
What is a primary defence?
Reducing the probability of an attack
What are three examples of primary defences?
- remaining hidden
- pretending to be dangerous
- reducing your odds of being selected (being in a group)
What are the two keys forms of mimicry seen in the natural world?
Mullerian and Batesian
Who proposed mullerian mimicry?
Fritz Muller
Who proposed batesian mimicry?
Henry Walter Bates
What is mullerian mimicry?
an honest signal
What is batesian mimicry?
a dishonest signal
What is the mullerian mimicry trade-off
Cost of conspiciousness vs benefits of dilution on the probability of being predated
- it depends on the number of noxious species in the predators range
What is the batesian mimicry trade-off?
Cost of conspicuousness vs benefits of being thought noxious by predator
- depends on proportion of noxious species to the ‘imposters’ in the predator’s range
What are the 4 benefits to being in a group?
- Dilution.
- Confusion.
- Selfish herding.
- Vigilance.
Example of dillution
Female wildebeest (Connochaetes taurinus) that defend their young from attack will have a higher lifetime reproductive success, compared to those that simply run with the herd.
What are the benefits of being in a group?
Individuals should choose to join groups of an optimum size to maximise their investment in the group ‘ideal’
What are four examples of secondary defence systems?
- distractions
- alarm calls
- mobbing
- Showing off
