Concept explainers
David Hills of Baylor University noted that three closely related species of leopard frog (genus Rana) exhibit substantial—but not complete—postzygotic reproductive isolation when crossed in the laboratory. Field surveys of numerous populations in Texas and surrounding states revealed that populations of the three species breed at various times during the year. Data on the breeding schedule of both allopatric and sympatric populations of these species are presented in the Figure below. Interpret the data in the figure and explain how they may demonstrate that these frogs experience prezygotic reproductive isolation in nature. What type of prezygotic reproductive isolation do the data suggest?
Source: D.M. Hillis. 1981. Premating isolating mechanisms among three species of the Rana pipiens complex in Texas and southern Oklahoma. Copeia 1981:312-319.
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Biology: The Dynamic Science (MindTap Course List)
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- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning