Practice Test | Chapter 22 | Campbell Biology in Focus Questions and Answers Revision Pack

Practice Test | Chapter 22 | Campbell Biology in Focus Questions and Answers Revision Pack.3 4 Imagine that part of a population of South American finches is blown by a storm onto an island far offshore and manages to survive and reproduce there for a period of 10,000 years. After that period, a climate change results in lower sea levels and the reconnection of the island with the mainland. Members of the formerly isolated island finch population can now interact freely with members of the original mainland population. Which observation would, by itself, lead you to conclude unequivocally that the island finch population had evolved into a distinct species, according to the biological species concept? ( Section 22.1) SHOW HINT The biological species concept defines a species as a population whose members interbreed successfully to produce viable, fertile offspring but who cannot produce viable, fertile offspring with members of other species. Which condition is necessary for speciation to occur? ( Section 22.1) SHOW HINT The preferred food of the island birds is quite different from the diet of mainland birds. Individuals from the different populations sometimes mate with each other, but all of the resulting eggs are sterile. Hybrid offspring of matings between individuals from the two populations do not look like either parent. Individuals from the different populations frequently direct courtship behavior toward members of the other population. The island birds all have red feathers, but the mainland birds have green feathers. interbreeding among neighboring populations mass extinction reproductive isolation sympatric speciation 10/27/21, 5:12 PM Practice Test | Chapter 22 | Campbell Biology in Focus, 3/e 5 6 The biological species concept hinges on reproductive isolation. Prezygotic barriers __________. ( Section 22.1) SHOW HINT These barriers hinder the fertilization of ova if members of sibling species attempt to mate. Three species of frogs, Rana pipiens, Rana clamitans, and Rana sylvatica, all mate in the same ponds, but they pair off correctly because they have different calls. This is a specific example of a __________ barrier, called __________. ( Section 22.1) SHOW HINT adaptive radiation prevent a hybrid zygote from developing into a viable, fertile adult prevent donkeys and horses from mating prevent fertilization of gametes from members of closely related species only occur in asexual organisms are necessary in order for speciation to occur postzygotic … hybrid breakdown postzygotic … mechanical isolation prezygotic … gametic isolation prezygotic … temporal isolation prezygotic … behavioral isolation 10/27/21, 5:12 PM Practice Test | Chapter 22 | Campbell Biology in Focus, 3/e 7 8 It occurs before mating and is due to different behaviors.