Anti-Predator Behaviour

Question 1

What 6 strategies do animals use to avoid predation?

Answer 1

1. Decreasing detection by predators
2. Avoiding attack or capture
3. Deception
4. Social defences
5. Chemical defences
6. Behaviour if captured

Question 2

What are the main strategies used to avoid detection?

Answer 2

• Camouflage
• Staying in cover (dense vegetation)

Question 3

Give an example of animal camouflage.

Answer 3

• Decorator crabs
• Decorate themselves with algae
• Those that use red algae survive longer than when they use other types of algae
• Due to algae containing a chemical that repels omnivorous fish

Question 4

Give an example of a pursuit deterrence signal.

Answer 4

Stotting in springbok gazelle

Question 5

What are 5 hypotheses to explain stotting in gazelles?

Answer 5

1. Unprofitability - shows they are fit & can easily run away.
2. Alarm signal - signals to other gazelles.
3. Confusion effect - confuses & distracts predator from focusing on 1 animal.
4. Social cohesion - enables gazelles to form groups & flee in a coordinated fashion.
5. Anti-ambush - lets gazelles see what’s ahead.

*Unprofitability hypothesis is most likely - 75% of time predator abandons chase.

Question 6

What are 5 other deterrence signals?

Answer 6

1. Erratic behaviour (e.g. random turns).
2. Misdirecting attacks (using signals, e.g. false head & eyes on tails).
3. Distraction displays - attempt to look injured.
4. Intimidation displays - attempt to look bigger, e.g. puffing feathers.
5. Startle displays - to deter attack & gain time for escape, e.g. caterpillars that inflate to look like a snake.

Question 7

What are 4 types of behaviour an animal can exhibit is captured?

Answer 7

1. Fighting back.
2. Fear screams.
3. Play dead.
4. Chemical defences.

Question 8

Give an example of a chemical defence in a species when captured by its predator?

Answer 8

• Sea hares - preyed upon by spiny lobsters.
• Release ink containing viscous substance that sticks to thr lobsters antennules & mouthparts.
• Blocks chemoreceptors & lobster’s response to food odours.

Question 9

What are the 3 types of mimicry? Give examples

Answer 9

• Batesian - a palatable species adopts markings or characteristics of an unpalatable species. Only the mimic benefits, e.g. monarch butterfly & viceroy butterfly.
• Mullerian mimicry - resembles another species but shares anti-predation attribute, e.g. honey bee & wasp.
• Acoustic mimics - E.g. burrowing owls making a hissing/buzzing sound that mimics a rattle snake.

Question 10

What are 2 social defences?

Answer 10

1. Group intimidation.
2. Mobbing together