BI 213 – Houck Study Questions Study Questions CH 24 Note: the answers are given in a different file so that you have a chance to answer these questions on your own first, and then check the answer sheet to see if your answers are correct. (1) Which one of the various species concepts identifies species based on the degree of genetic exchange between their gene pools? (a) phylogenetic (b) ecological (c) biological (d) morphological (e) paleontological (2) If two subspecies, A and B, are not considered separate species, even though they cannot interbreed, then… a) they are groups that are endemic to isolated geographic regions. b) gene flow between A and B may exist through other related subspecies. c) they have eliminated postzygotic barriers but not prezygotic barriers. d) gene flow has ceased and genetic isolation is complete. e) their diploid gametes are produced by nondisjunction. (3) Some species of mosquitos live in brackish water, some in running fresh water, and others in stagnant water. What type of reproductive barrier is most obviously separating these different species? a) habitat isolation b) temporal isolation c) behavioral isolation d) gametic isolation e) postzygotic isolation Which of the following must occur during a period of geographic isolation in order for two sibling species to remain genetically distinct following their geographic reunion in the same home range? a) prezygotic barriers b) postzygotic barriers c) ecological isolation d) reproductive isolation e) temporal isolation (4) (5) Two species of frogs belonging to the same genus occasionally mate, but the offspring do not complete development. What is the mechanism for keeping the two frog species separate? a) the postzygotic barrier called hybrid inviability b) the postzygotic barrier called hybrid breakdown c) the prezygotic barrier called hybrid sterility d) gametic isolation e) adaptation BI 213 –Study Questions CH 24 (Cont’d) pg. 2 (6) Which example below will most likely guarantee that two closely related species will remain distinct biological species? b) convergent evolution c) hybridization a) colonization of new habitats d) geographic isolation from one another e) reproductive isolation from one another (7) A rapid method of speciation that has been important in the history of flowering plants is a) genetic drift. b) paedomorphosis. c) a mutation in the gene controlling the timing of flowering. d) behavioral isolation. e) polyploidy. (8) According to the concept of punctuated equilibrium, the "sudden" appearance of a new species in the fossil record means that a) the species is now extinct. b) speciation occurred rapidly in geologic time. c) speciation occurred in one generation. d) speciation occurred instantaneously. e) the species will consequently have a relatively short existence, compared with other species. (9) Speciation… (a) occurs at such a slow pace that no one has ever observed the emergence of new species. (b) occurs only by the accumulation of genetic change over vast expanses of time. (c) occurs via anagenesis and cladogenesis, but only the latter increases biodiversity. (d) proceeds at a uniform tempo across all taxa. (e) must begin with the geographic isolation of a small, frontier population. (10) Which term below is a pattern of evolutionary change involving the accumulation of changes that gradually transform a species into a species with different characteristics? a) microevolution b) cladogenesis c) macroevolution d) anagenesis e) branching evolution BI 213 –Study Questions CH 24 (Cont’d) pg. 3 (11) In which of the following groups has sympatric speciation been most important? a) animals b) plants c) bacteria d) fungi e) protozoa (12) The products of Hox genes _____ a) may cause polyploidy in some plants b) control the rate of timing and developmental events c) can cause paedomorphosis control allometric growth d) provide positional information in animal embryos (13) Which of the following would be an example of macroevolution? a) evolution of antibiotic resistance in a strain of E. coli b) evolution of polymorphism in a butterfly, with each morph mimicking a different protected butterfly c) evolution of modern humans, Homo sapiens, from australopithecine ancestors d) evolution of insecticide resistance in populations of insect pests treated through the years with DDT (14) Which of the following statements about speciation is correct? a) The goal of natural selection is speciation. b) When reunited, two allopatric populations will not interbreed. c) Natural selection chooses the reproductive barriers for populations. d) Prezygotic reproductive barriers usually evolve before postzygotic barriers. e) Speciation is included within the concept of macroevolution.