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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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- Decide whether each of the following scenarios would lead to prezygotic or postzygotic reproductive isolation: a) Dragonflies from two different populations have genitals that do not match, so they can't mate successfully [Select ] b) Two different species of fish have very different courtship displays, but they can mate and produce a non-fertile offspring [Select] c) One species of plant flowers in the winter, while another flowers in early spring [ Select ] d) The gametes of two tree species can fuse, but a zygote does not form [ Select ] e) A mountain range separates two populations of snakes I Select]arrow_forwardWHAT IF? Suppose two bird species live in a forestand are not known to interbreed. One species feeds andmates in the treetops and the other on the ground. Butin captivity, the birds can interbreed and produce viable,fertile offspring. What type of reproductive barrier mostlikely keeps these species separate in nature? Explain.arrow_forwardWhat data would suggest that a species evolutionary history includes sexual selection as a mechanism that helped shape the species? If males and females are significantly different from each other (sexual dimporphism) If males and females form different social groups (i.e. herds are formed from either males or females but not both) If some males reproduce with multiple females while other males do not reproduce If males engage in "risky" behaviorarrow_forward
- 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_forwardMatchplease: 12345 pre-zygotic: geographic isolation 12345 pre-zygotic: behaviour 12345 post-zygotic: hybrid sterility 12345 pre-zygotic: timing 12345 post-zygotic: hybrid inviability 1. A species of salamanders is separated by a new road 2. Wolves tend to eat dogs. 3. A species of trout has members who mate in either April or June 4. A mule is not fertile. 5. Goats and sheep can mate, but the offspring are still-born.arrow_forwardPlease solvearrow_forward
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- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning