Final answer:
Sexual dimorphism is the term for when males and females of the same species become more physically distinct from each other. Habitat isolation and different environmental pressures can cause this divergence. Over time, these changes may lead to speciation, where populations become reproductively and genetically independent from one another.
Step-by-step explanation:
Sexual dimorphism occurs when male and female animals of the same species begin to look less and less similar, often due to different selective pressures acting on the sexes.
For example, males might evolve elaborate ornaments or displays if those traits help them to attract mates, while females may evolve traits that are advantageous for survival or selecting high-quality mates.
In cases where populations become separated, a process known as habitat isolation can lead to these differences becoming more pronounced over time.
As the populations are exposed to different environments and selective pressures, traits including size, coloration, and reproductive behaviors may diverge further.
When environmental changes occur, such as increased water turbidity leading to color distinctions being less visible, organisms may adapt new mate-selection strategies, which can also contribute to sexual dimorphism.
This situation can lead to further evolutionary divergence between populations or species, a concept sometimes referred to as character divergence or speciation.