Final answer:
Research on Hawaiian cricket speciation has found that assortative mating, female preference for singing pulse rate, and the genetic link between preference and pulse rate are all accurate factors contributing to speciation.
Step-by-step explanation:
Research on speciation of Hawaiian crickets has led researchers to conclude that all of the options provided are accurate. These cricket species have diverged by a mechanism known as assortative mating, where females of different species exhibit strong preferences for the singing pulse rate of the males of their own species. Furthermore, female preference for male singing pulse rate is genetically linked to the combination of genes regulating the singing pulse rate of males, demonstrating a mate recognition system that functions as a reproductive isolating mechanism.
Such patterns are observed in crickets like Gryllus pennsylvanicus and Gryllus firmus, which have distinct soil preferences leading to habitat isolation. Over time, this reproductive and genetic independence resulted in the divergence between the two cricket species. Therefore, the correct response to the student's question is option 4: All of the above are accurate.