Question

*22. Which of the isolating mechanisms listed in Table 26.2 have partly evolved between apple and hawthorn host races of Rhagoletis pomenella, the apple maggot fly? TABLE 26.1 Types of reproductive isolating mechanisms Type Characteristics Prezygotic Acts before a zygote has formed Ecological Differences in habitat; individuals do not meet Temporal Reproduction takes place at different times Mechanical Anatomical differences prevent copulation Behavioral Differences in mating behavior prevent mating Gametic Gametes are incompatible or not attracted to each other Postzygotic Acts after a zygote has formed Hybrid inviability Hybrid zygote does not survive to reproduction Hybrid sterility Hybrid is sterile Hybrid breakdown F1 hybrids are viable and fertile, but F2 are inviable or sterile