Question

which of the following must occur for speciation to happen?
geographic isolation
reproductive isolation
temporal isolation
behavioral isolation

Explanation:

Speciation is the process of forming new species. According to the biological species concept, a species is a group of organisms that can interbreed and produce fertile offspring. Reproductive isolation means that two groups of organisms cannot interbreed or produce fertile offspring. Without reproductive isolation, the two groups would still be part of the same species. Geographic isolation (like a mountain range separating populations) can lead to speciation over time by allowing genetic divergence, but it is not an absolute must - some sympatric speciation (speciation in the same geographical area) can occur. Temporal isolation (different breeding times) and behavioral isolation (different mating behaviors) are types of reproductive isolation mechanisms. But the over - arching requirement for speciation is reproductive isolation.

Answer:

reproductive isolation