Salamander reproduction reproductive isolation

Sexual isolation has arisen among numerous species of geographically isolated populations of salamanders (review by Arnold et al., 1993). Behavioral experiments indicate that the degree of reproductive isolation is stronger between sympatric species of large Plethodon than it is between allopatric populations of these species (Reagan, 1992). Sexual isolation may be due to species-specific differences in the chemosensory systems... 

Arnold, S.J., Reagan, N.L, Verrell, PA. 1993. Reproductive isolation and speciation in plethodontid salamanders. Herpetologica 9 216-228. 

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