Explain haplodiploidy and its relevance to Hymenoptera reproduction.

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Multiple Choice

Explain haplodiploidy and its relevance to Hymenoptera reproduction.

Haplodiploidy is a sex-determination system used by many Hymenoptera (ants, bees, wasps) where the fertilization status of an egg determines its sex. Fertilized eggs become diploid females, while unfertilized eggs develop into haploid males. This means males carry only the mother’s genes, while females carry both maternal and paternal genes. In reproductive terms, this gives the queen a mechanism to influence the ratio of daughters to sons by deciding whether to fertilize an egg, which is why colonies often have many females (workers or new queens) and fewer drones. This system also shapes social genetics. Because sisters can be more genetically related to each other than to their own offspring, kin selection can favor cooperative brood care and the evolution of eusociality in some species. Keep in mind that some Hymenoptera can deviate from this pattern through mechanisms like parthenogenesis that produce females from unfertilized eggs, but the described fertilized-diploid, unfertilized-haploid rule is the classic pattern.

Haplodiploidy is a sex-determination system used by many Hymenoptera (ants, bees, wasps) where the fertilization status of an egg determines its sex. Fertilized eggs become diploid females, while unfertilized eggs develop into haploid males. This means males carry only the mother’s genes, while females carry both maternal and paternal genes. In reproductive terms, this gives the queen a mechanism to influence the ratio of daughters to sons by deciding whether to fertilize an egg, which is why colonies often have many females (workers or new queens) and fewer drones.

This system also shapes social genetics. Because sisters can be more genetically related to each other than to their own offspring, kin selection can favor cooperative brood care and the evolution of eusociality in some species. Keep in mind that some Hymenoptera can deviate from this pattern through mechanisms like parthenogenesis that produce females from unfertilized eggs, but the described fertilized-diploid, unfertilized-haploid rule is the classic pattern.

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