Terms in this set (24)

-block fertilization from occurring, such barriers typically act in one of three ways:
-By impeding members of different species from attempting to mate
-By preventing an attempted mating from being completed successfully
-By hindering fertilization if mating is completed successfully
-Habitat Isolation
Two species that occupy different habitats w/in the same area may encounter each other rarely, if at all, even though they are not separated by some physical barrier (mountain range)
Two species of garter snakes live in the same geographic areas, but one lives mainly in water and the other on land
-Temporal Isolation
Species that breed during different times of day, different seasons, or different years cannot mix their gametes
-Geographic ranges of the western and eastern spotted skunk overlap, but western mates in summer and eastern in winter
-Behavioral Isolation
Courtship rituals that attract mates and other behaviors unique to a species are effective reproductive barriers, even btween closely related species
Such behavioral rituals enable mate recognition - a way to identify potential mates of the same species
Blue footed boobies of the Galapagos mate only after a courtship display unique to their species, the male must high-step dance which calls attention to his bright blue feet
-Mechanical Isolation
Mating is attempted but morphological differences prevent its successful completion
Shells of two species of snails spiral in different directions, as a result the snails' genital openings are not aligned, and mating cannot be completed
-Gametic Isolation
Sperm of one species may not be able to fertilize eggs from another species, as the sperm may not be able to survive in the reproductive tract of females of the other species
Biochemical mechanisms may prevent the sperm from penetrating the membrane surrounding the other species' eggs