"The problem, as David Wake now admits, is that these salamanders never comprised a continuous 'ring,' but were separated geographically on and off over millions of years, so it’s entirely possible that the reproductive isolation did not occur through the gradual attenuation of gene flow with distance." — Jerry Coyne, Why Evolution Is True보관됨 2014-01-11 - 웨이백 머신, retrieved 2014-01-10; citing Speciation; Coyne, J., and Orr, A., c2004 ISBN0878930914
"The problem, as David Wake now admits, is that these salamanders never comprised a continuous 'ring,' but were separated geographically on and off over millions of years, so it’s entirely possible that the reproductive isolation did not occur through the gradual attenuation of gene flow with distance." — Jerry Coyne, Why Evolution Is True보관됨 2014-01-11 - 웨이백 머신, retrieved 2014-01-10; citing Speciation; Coyne, J., and Orr, A., c2004 ISBN0878930914
