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WHAT IF? Consider two species that diverged while geographically separated but resumed contact before reproductive isolation was complete. Predict what would happen over time if the two species mated indiscriminately and (a) hybrid offspring survived and reproduced more poorly than offspring from intraspecific matings or (b) hybrid offspring survived and reproduced as well as offspring from intraspecific matings.
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- Suppose the phylogenetic species concept (PSC) were preferred over other species concepts, such as the BSC. What would be the implications for (a) discourse on the evolutionary mechanisms of speciation; (b) studies of species diversity in ecological communities; (c) estimates of species diversity on a worldwide basis; and (d) conservation practices under such legal frameworks as the U.S. Endangered Species Act?arrow_forwardWhich of the following reproductive isolating mechanisms prevents mating because the two species are physically unable to mate? (a) ecological isolation (b) behavioral isolation (c) mechanical isolation (d) gametic isolation (e) all of the abovearrow_forwardPlease Help! Q1) Butterflies in Africa (species 1) pollinate just one species of flower with a short corolla reducing the variation in the length of the tongue of its pollinators. Butterflies in Europe (species 2) have variable lengths as they pollinate several different species of flowers. What is the mechanism shaping the length of the tongue in species 1?______ Q2) A variation on what morphological trait made the difference between life and death among all surviving finches in the draught of 1977? (one-word answer)arrow_forward
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- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning