In the case of the Lake Victoria cichlids, sympatric speciation has been shown to be driven by __________.

• A. polyploidy
• B. habitat differentiation
• C. mechanical isolation
• D. postzygotic barriers
• E. sexual selection

Answer: (E)

Verified step by step guidance

1. Understand the concept of sympatric speciation: Sympatric speciation occurs when new species evolve from a single ancestral species while inhabiting the same geographic region. This is different from allopatric speciation, where geographic isolation is a key factor.
2. Identify the mechanisms that can lead to sympatric speciation: These include factors like polyploidy, habitat differentiation, mechanical isolation, postzygotic barriers, and sexual selection.
3. Focus on sexual selection: Sexual selection is a form of natural selection where certain traits increase an individual's chances of mating and passing on their genes. In the case of Lake Victoria cichlids, sexual selection has been a significant driver of speciation.
4. Consider how sexual selection can lead to speciation: In Lake Victoria cichlids, variations in male coloration and female preferences for these colors can lead to reproductive isolation, even without geographic barriers.
5. Conclude that sexual selection can drive sympatric speciation: The preference for specific traits can lead to the formation of distinct species within the same environment, as seen in Lake Victoria cichlids.