These factors are classified as prezygotic factors and they exert their influence before fertilization moment.
Temporal isolation is one of reproductive isolation factor and it is caused by lack of synchronization of breeding cycles.
Behavioral isolation is other barricade to gene movement between sympatrics. In many species of insects, animals, birds or fishes, audio-visual or chemical signals are important in mating. Hence, different species use different mating sounds, color patterns or various concentrations of chemical compounds.
Ecological isolation hampers the meeting of the forms because, they live in the same geographic area but they occupy different places.
Gametic isolation occurs when gamet is delivered but if the egg does not belong to the same species, the fertilization process does not take place.