Questions to practice

19. A dairy cow in NZ faces an HLI of 72 with moderate humidity and no wind. What behavioural signs might indicate high heat stress if rest deprivation is minimal, and how would you test shade priority experimentally?

Answer: A dairy cow in New Zealand with a Heat Load Index of 72, moderate humidity, and no wind may show heat stress by spending more time in shade. To test how much the cow values shade, you could put a small barrier in front of the shaded area and see if it will cross it when it is not rest deprived.

20. Climate projections show increasing cold stress events in a dairy region. How would you use a shelter vs rest trade-off test to identify when to provide extra shelter?

Answer: In areas where cold stress is becoming more common, you can use a shelter versus rest test to decide when to give cows extra shelter. This means offering a choice between shelter and resting, under different cold, wind, and wet conditions, and seeing when cows give up rest to use shelter.

21. Compare and contrast the evolutionary drivers and ecological conditions that favour monogamy, polygyny, and polyandry, using specific examples from lecture.

Answer:

Monogamy is favoured when mates are hard to find or when both parents are needed for offspring survival. For example, California mice in cold climates have higher litter survival (30% → 80%) when fathers help. Polygyny occurs when males can defend resources or groups of females, as in pseudoscorpions (resource-defence) or sage grouse (lek). Polyandry happens when male care is the limiting resource, causing females to compete, as in northern jacanas and seahorses. These systems are shaped by how resources, mates, and care are distributed.

22. Discuss the role of sexually antagonistic coevolution in shaping both morphological and behavioural traits, illustrating with at least three taxa from the lecture (e.g., dung flies, water striders, penduline tits).

Sexually antagonistic coevolution (SAC) is an arms race between sexes over reproduction. In dung flies, males use genital spines to remove rival sperm but injure females, who counter by shaking them off. In water striders, males have grasping legs while females have abdominal spines to resist mating. In penduline tits, females bury eggs to delay male desertion, while males desert sooner if eggs are visible. 

23. Explain how integrating environmental measurements, behavioural priorities, and motivational state allows researchers to infer subjective experiences in animals. Use examples from heat and cold stress trade-off studies.

Environmental measures like the Heat Load Index or cold stress values quantify physical conditions but not discomfort. Behavioural trade-offs, such as choosing shade over rest, show what animals value under stress. Motivation also matters: cattle sacrifice rest for shade under high heat plus 24-hour rest deprivation, and they seek shelter sooner in cold when rest-deprived. Combining environmental data, behaviour, and motivation reveals when animals are likely uncomfortable.

. Give one example each of:

a) Egg attendance without feeding

b) Provisioning in insects

c) Mouth brooding in fish

Answer:

a) Female shield bugs guarding eggs

b) Burying beetles feeding larvae

c) Male cichlid carrying eggs in buccal cavity

10. Which is NOT a potential benefit of extra-pair copulations for females?
    A. Increased genetic diversity of offspring
    B. Access to better parental care from social mate
    C. Fertilisation insurance
    D. Avoidance of inbreeding

12. The __________ critical temperature is the point below which animals must increase metabolic heat production to maintain body temperature.

lower

13. The Heat Load Index combines factors such as temperature, humidity, wind speed, solar radiation, and __________ temperature.

Previous night

Section E – Graph/Scenario Interpretation

15. You are shown a graph of shade use vs. temperature for cattle, with three lines: 0-hour rest deprivation, 12-hour rest deprivation, and 24-hour rest deprivation. The 24-hour line rises steeply after HLI 29.

Explain what this means about the priority of shade for cows.

“Cows value shade more when heat stressed, and even more when rest deprived. The steep increase after HLI 29 for 24-hour deprivation shows shade becomes a top priority under extreme conditions.”

18. List the three Rs of animal research and give one example of each in an animal behaviour study.

Replacement means using non-animal based methods where possible.

Example from class: analysing recorded bird song playback experiments instead of doing new captures.

Reduction means limiting the number of animals used in experiments.

Example from class: using within-subject designs for testing mate choice so each animal serves as its own control.

Refinement means improving methods to reduce pain, stress, or suffering. 

Example from class: training dairy cows to voluntarily enter a testing area to measure shade use, rather than forcing them in.

6. Compare the signal-of-need and signal-of-quality hypotheses, and give one species example for each.

The signal of need hypothesis states that begging intensity reflects hunger, encouraging parents to feed the needier chick. 

In blue-footed boobies, parents preferentially feed chicks with brighter gape colour, which reflects better health and condition rather than immediate hunger. This supports the signal-of-quality hypothesis because the display signals the chick’s overall viability.

The signal of quality hypothesis states that displays show an offspring's intrinsic condition or viability, encouraging parents to feed the higher quality chick.

In Nazca boobies, chicks beg more intensely when they are hungrier, and parents respond by feeding them more. This supports the signal-of-need hypothesis because the begging reflects the chick’s immediate nutritional requirement rather than its long-term quality.

6. Compare social monogamy and genetic monogamy, using examples from class.

Social monogamy is when a pair bond is observed but the genetic offspring may come from other mates. 

Superb fairy-wrens (from class) form long-term pair bonds but have high rates of extra-pair copulations, meaning the social male often raises offspring not genetically his own.

Genetic monogamy is when all offspring come from the same pair.

Wandering albatross (from class) form life-long pair bonds, and genetic testing shows both partners only mate with each other, so all chicks are from the same genetic parents.

(Circle one)

9. Which of the following is NOT a potential direct benefit of polyandry?

A. Fertility assurance

B. Access to nuptial gifts

C. Increased offspring genetic diversity

D. Avoidance of infanticide

10. In siblicidal species like the Nazca booby, siblicide is most likely when:
    A. Food is abundant
    B. Food is scarce
    C. Parents provide equal feeding to all chicks
    D. Adults breed in colonies

15. Cows in a rest-vs-shade trade-off test choose shade more often when HLI is high and rest deprivation is minimal. What does this tell you about shade’s priority?

This shows that shade is a high priority for cows under heat stress, even when they are not lacking rest. It means that access to shade can be essential for maintaining welfare during hot conditions.