29. What are the two most important evolutionary mechanisms in allopatric speciation by founder effect? A. Disruptive/Diversifying selection & Stabilizing/Balancing selection B. Disruptive/Diversifying selection & Gene flow C. Directional selection & Gene flow D. Directional selection and Genetic drift E. Stabilizing/Balancing selection & Genetic drift
30. Biomedical research into human diseases and disorders relies extensively on non-human animal models. Transference of research findings to the treatment of human conditions is in large measure dependent on:
31. Which of the following statements best describes the rationale for applying the principle of parsimony in constructing phylogenetic trees?
32. Great Smoky Mountains National Park is bisected by a two-lane highway, U.S. 441. Most organisms can cross this barrier, either as individuals or in the form of spores or seeds. However, some low dispersing species may not be able to cross this barrier or will not. What may be happening to the populations of those species that are effectively separated by the highway barrier?
33. Several population or species pairs of birds that reside and breed in North America were geographically isolated into eastern and western populations for tens of thousands of years during the Pleistocene glaciation. Due to post-Pleistocene warming and human landscape change since the 16thcentury, the breeding range of these populations/species have expanded and now overlap. If the formerly isolated species/populations readily breed, but the hybrid eggs do not hatch, what is most likely to happen? A. Selection will act on both populations to produce hybrid embryos that hatch. B. Selection will operate to increase prezygotic isolation of the two species/populations. C. Prezygotic isolating mechanisms such as mating calls or behavioral differences between the two populations/species will decrease. D. Postzygotc isolation between the two populations/species will decrease. E. A stable hybrid zone will form.