Mates, Kin and Animal Strategies · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Mates, relatives and animal strategies

Science · Animals of the World · ages 12-13
Name ______________________   Date ____________

  1. Which description directly identifies a possible effect on mate choice?

    • A cheetah's running speed helps it catch prey.
    • A peacock display attracts females.
    • A camel's stored fat supplies energy during a food shortage.

  2. What is sexual selection?

    • Selection through differences in mating success
    • Selection through differences in finding food
    • Selection through differences in resistance to disease

  3. A worker honeybee can help shared gene copies pass on by helping related hive members survive and reproduce.

    Circle one:   True   False

  4. In a model, tail length and mate preference are inherited. Females favour longer-tailed males. Before costs limit the trend, what could happen?

    • The trait and preference can reinforce each other.
    • The preference can change tails within one male's life.
    • The tail trait can spread without affecting mating success.

  5. In a model, a meerkat's warning helps close relatives raise more young but costs the caller reproductive success. Which process could favour an inherited tendency to warn?

    • Mate choice
    • Direct survival benefits
    • Kin selection

  6. A new toy model values a resource at 6 points and an injury at 12 points. A hawk averages -3 against a hawk and gets 6 against a dove. Why is its score lower against another hawk?

    • The resource has a lower value in that pairing.
    • Injury costs lower its score.
    • The opponent shares the resource without fighting.

  7. In a simplified Hamilton's-rule model, r = 0.5. Helping adds B = 10 reproductive-success units for relatives and costs the helper C = 4 of the same units. What is r x B?

    Answer: ______________

  8. An animal's behaviour looks playful. How should a cognitive ethologist investigate an explanation about its feelings?

    • Judge feelings from resemblance to human play.
    • Use repeated behaviour as proof of one particular feeling.
    • Compare behaviour, body signals and other explanations.
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Mates, relatives and animal strategies W1-mt_YNrrNE23dZ-s1

  1. A peacock display attracts females. · The peacock description directly connects a display to attracting potential mates. The other descriptions concern food and energy.
  2. Selection through differences in mating success · Sexual selection concerns differences in mating success, including mate choice and competition for access to mates.
  3. True · Shared copies can pass through relatives' offspring, even when the helper does not reproduce.
  4. The trait and preference can reinforce each other. · In this model, inherited tail differences affect mating success, and the inherited preference can reinforce the trend across generations.
  5. Kin selection · Kin selection compares reproductive benefits to relatives, weighted by relatedness, with the helper's cost.
  6. Injury costs lower its score. · Two hawks fight. Each averages (6 - 12) / 2 = -3 points because injury is costly. A hawk facing a dove gets the resource without that escalated fight.
  7. 5 · 0.5 x 10 = 5. Since 5 > 4, the condition r x B > C is met within this model.
  8. Compare behaviour, body signals and other explanations. · Scientists compare evidence and alternative explanations. Resemblance or repeated behaviour alone does not prove an animal's exact feelings.
Worksheet · LightMySky