Final answer:
Sexual selection is the most probable cause of sexual dimorphisms in many species. Males often have more variance in reproductive success, resulting in selection pressure for larger body size and elaborate ornaments.
Step-by-step explanation:
Sexual selection is the most probable cause of sexual dimorphism, differences in the size or appearance of males and females in many species. Sexual dimorphisms arise due to differences in reproductive success between males and females. Males often have more variance in their reproductive success, leading to selection pressure for larger body size and elaborate ornaments to attract females.
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