Which mechanism would most likely NOT contribute to sympatric speciation?

Sympatric speciation occurs when new species arise within the same geographic area, typically due to reproductive isolation mechanisms rather than physical separation. In this context, geographical isolation does not typically contribute to sympatric speciation. This is because geographical isolation involves barriers that physically separate populations, leading to allopatric speciation, where populations diverge due to being separated.

On the other hand, mechanisms such as behavioral isolation, temporal isolation, and mechanical isolation help facilitate sympatric speciation by allowing populations to diverge reproductively without geographical barriers. Behavioral isolation relies on differences in mating behaviors, temporal isolation involves differences in breeding seasons or times, and mechanical isolation refers to physical differences that prevent successful mating. These mechanisms enable populations to coexist in the same area while gradually evolving into separate species, which is the essence of sympatric speciation.