Robertson and Weatherhead proposed that this hypothesis would hold under the assumption that male promiscuity was advantageous in populations with a one-to-one sex ratio. For 10 points each:
[10h] Name this hypothesis, which states that sexual selection arises from females prioritizing mates that maximize the fitness of their male offspring.
ANSWER: sexy son hypothesis
[10m] Selection across generations for male ornamentation to create sexy sons creates this phenomenon. This positive feedback loop creates extreme sexual dimorphism, as seen in peacocks.
ANSWER: Fisherian runaway [or runaway selection]
[10e] The Hamilton–Zuk hypothesis states that sexual ornamentation is attractive because it signals resistance against these organisms. These organisms benefit from harming a host without killing the host outright.
ANSWER: parasites [accept parasitism]
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