What does sexual dimorphism refer to in biology?

Sexual dimorphism refers to the differences in size, ornamentation, or behavior between the two sexes of the same species. This phenomenon can be observed across a wide range of organisms, where males and females exhibit distinct physical traits or behaviors that can aid in attracting mates, competing for resources, or improving offspring survival. For example, in many bird species, males may have brighter feathers or elaborate displays to attract females, while females may have more subdued coloration that provides better camouflage. This differentiation often plays a crucial role in the mating system and reproductive strategies of the species involved.

The other responses do not accurately describe sexual dimorphism. For instance, having all individuals of the same size does not capture the essence of sexual differentiation. Similarly, organisms with the same genetic makeup or species that inhabit the same environment do not convey the concept of physical or behavioral differences between sexes. These definitions lack the specific focus on the variance between male and female forms that is central to understanding sexual dimorphism.