Practice question

Altruism benefits recipient at cost to actor, reducing direct fitness but increasing indirect fitness via relatives sharing genes. Hamilton's rule rb>c predicts altruism evolves when relatedness times benefit exceeds cost. Relatedness 0.5 for siblings, 0.25 for half-sibs, 0.125 for cousins, 0.75 for haplodiploid sisters explains worker sterility in Hymenoptera. Inclusive fitness includes direct plus indirect components. Eusociality, alarm calls and reciprocal altruism exemplify. Hence rb > c captures kin selection logic underlying altruistic behavior. This concept integrates genetics, ecology and molecular evidence, frequently tested in NEET, GATE and CSIR-NET, highlighting links between genotype, phenotype and