Name:______________________________________________NPB 102, Animal Behavior Winter 2009 Exam 1 Student ID #_____________________________ Instructions: This exam has 5 pages, none of them blank. Make sure that your copy is complete before beginning. Write your name on every page and if you want us to be able to return your exam to you by leaving it in the hall boxes in Briggs hall, sign the authorization at the end of the exam. Read each question very carefully to be certain that you understand what is being asked. We will not answer any questions about the exam during the exam! Please do not come up to ask an instructor about any exam questions during the exam. If you believe a question is a bad question you may make a note on your exam for the instructors to consider. Multiple Choice: (1 pt each) Circle the letter of the one best choice to complete each of the following: 1) Which of the following is a potential proximate hypothesis to explain the expression of infanticidal behavior in male lions? a) Male lions that practice infanticide reduce the overall food demands of the pride, leading to more food for remaining offspring, which therefore grow more quickly and become stronger, healthier adults. b) Individual males that practice infanticide leave more surviving offspring because they can begin siring their own young sooner if they remove the young that are present when they first join a pride. c) Lions belong to a lineage of big cats that all inherited a tendency for infanticidal behavior from a common ancestor. d) All of the above. e) None of the above. 2) Evidence suggesting that the V1-a Receptor gene explains the difference in mating system (monogamy versus polygyny) between prairie voles and others such as montane and meadow voles includes: a) Male prairie voles express this gene in the ventral pallium of their brains, whereas male meadow and montane voles do not. b) Male meadow and montane voles lack this gene entirely, whereas male prairie voles possess it. c) Experimental addition of extra copies of the V1-a Receptor gene into any part of the brains of male prairie voles leads the males to huddle more with female partners. d) Male meadow voles that receive infusions of the prairie vole version of the V1-a Receptor gene into the ventral pallium of their brains associate more closely with their mates than do control males that receive copies of a different gene into the same area. e) All of the above. 3) Mapping the behavioral trait of song learning onto a phylogenetic tree of all bird orders would be most useful if you wanted to evaluate the validity of which of the following hypotheses? a) Song learning was the ancestral trait at the point when parrots diverged from other orders, and has simply been retained in the more recently-diverged lineages that display it. b) Song learning enhances male reproductive success under circumstances of high environmental variation. c) Song learning is facilitated by a particularly well-developed Area X within songbirds. d) Song learning is a “critical period” phenomenon that depends on experience early in life. e) Song learning is guided by a “neural template.” 1 5) Which of the following is an ultimate explanation for the fact that female red-winged blackbirds discriminate more carefully against songs that aren’t the “real thing” (e. Why do male song sparrows have multi-song repertoires? __UF__1.. So. who listen from the noisier environment at the tops of the reeds.4) Which of the following procedures would be likely to completely eliminate ability to sing if performed on an adult male songbird? a) Unilaterally (on one side only) lesioning (destroying) HVC. Indicate what kind of hypothesis each is with a P or U for Proximate or Ultimate. if you think one of them is Proximate and Causal. __UF__3. c) Unilaterally lesioning RA. c) Females listen to the songs from their nests. leading to a multi-song repertoire. Male song sparrows are less likely to intrude on a territory of a male that sings a multi-song repertoire. d) Females would suffer a greater reproductive cost if they failed to reject mating advances from a bird of the wrong species than males would if they mistakenly sang back at a bird of another species. Young males select songs from their over-produced repertoire that match songs sung by several neighbors. 6) The “two voices” in the syrinx are: a) The left and right medial tympanic membranes. as well as a D (developmental: How does it Develop?). Observation and question 1 (8 pts): The crystallized song of male song sparrows consists of a repertoire of several different song types. e) None of the above.g. C (causal: What Causes it?). b) High estrogen levels of breeding females cause their HVC neurons to be very precisely tuned to respond preferentially to fine details of the male song. e) The left and right syringial musculature. C” in front of it. d) Bilaterally severing (cutting) all axonal connections between HVC and RA. e) Bilaterally severing all axonal connections between lMAN and RA. b) Bilaterally (on both sides) lesioning Area X. you would write “P. 2 . so they are better able to hear the fine details of the songs than the males. E (evolutionary history: How did it Evolve?) or F (fitness: What is its Fitness value?). __UF__2. for instance. Female song sparrows prefer males with multi-song repertoires. b) The two sides of the intraclavicular air sac c) The left and right pairs of medial and lateral labia located at the top of each bronchus. Distinguishing Proximate and Ultimate Hypotheses: Each of the following observations and questions is followed by a list of hypotheses. __PD__4. mockingbird copies of male red-winged blackbird song) than males do? a) Male red-winged blackbirds have inferior auditory discrimination abilities compared with females. Having a choice of several different songs they can use permits them to conserve energy and reduce risk of injury by regulating the intensity of aggressive encounters with other males. which are protected from wind. d) The left and right tracheal cartilages. so they memorize. Innate (unlearned) song is the ancestral condition in birds. Adult male Cassin’s finches have mostly stopped singing by the time young males are old enough to begin memorizing songs. so males that have augmented their note repertoires by adding heterospecific (other species’) sounds to their songs have better success attracting females. Pigeons and doves lack anything like the rostral “learning circuit” found in brains of male songbirds. Female Cassin’s finches respond favorably to larger song repertoires. __UF__2. 3 . Cassin’s finches belong to a group of closely-related bird species that all display this same behavior. but they do not learn their songs. and this favors individuals that use a mating signal that is rigidly genetically controlled. any and all bird sounds they hear early in life. Observation and question 3 (8 pts): Pigeons and doves sing. Selection against hybrids has been particularly strong in pigeons and doves. suggesting that they inherited this trait from an ancestor that also displayed this behavioral trait. and pigeons and doves have simply inherited this trait from the ancestor they share with other birds. Male Cassin’s finches lack any innate predisposition to copy conspecific (their own species) sounds from the total acoustic environment. __PD(C ok)__4. Why do they do this? __PD__1. Pigeons and doves lack any pathway for auditory information to feed into their song control system. __UE__4. __PD__2.Name:______________________________________________ NOTE: For the two questions on this page follow the same instructions as for Observation and question 1. above: Observation and question 2 (8 pts): Male Cassin’s finches include sounds from numerous other bird species in their crystallized songs. __PC(D ok)__3. Why do pigeons and doves not learn their songs? __UE__1. so they tend to memorize sounds from other bird species that are still singing at this time. and later try to duplicate. __UF__3. the birds might adjust which song types they select from their overproduced repertoire (during the sensory-motor phase of song development) based on the responses they get to the over-produced songs they sing when establishing territories. they are not potentially mutually exclusive of one another. It is entirely possible that the mechanism that explains the difference in female response is accurately identified by hypothesis 2. (5 pts) How do the songs of male great tits differ between populations living in densely-vegetated forests versus more open woodlands? Describe one hypothesis that could explain this difference. (2) Female white-crowned sparrows have neurons in their HVCs that respond more strongly to songs matching the local dialect than to other songs. No. both of which are potential answers to the question: “Why do female white-crowned sparrows respond more strongly to local than to foreign dialect songs?” (1) Females who solicit copulations from males singing the local song dialect have higher reproductive success because those males tend to possess gene combinations that are well-suited to the conditions in the local area. but that the adaptive significance of the behavior is to improve reproductive success of females by making it more likely that they are most likely to mate with the “best” males. Further. Are these two hypotheses potentially mutually exclusive alternatives? Explain your answer. specifically regarding the potential benefits to females’ reproductive success if they encourage males from the local area to mate with them.Paragraph answers: Answer each of the following with a paragraph. Be sure to read the questions carefully. and fewer sexual solicitation displays when they hear songs of a distant foreign dialect area. and this positive social feedback received during singing practice could provide the proximate information that leads to the birds preferentially crystallizing mostly low-pitched songs in the forest habitat. For instance. indicate whether this is an ultimate or a proximate hypothesis. it is common for them to give more sexual solicitation displays when they hear songs of the dialect area in which they live. and this neural response in HVC is linked to brain centers that activate solicitation behavior. Consider the following two hypotheses. 2. You also could answer this with a proximate explanation. Specifically. (5 pts) Female white-crowned sparrows show stronger sexual responses to some white-crowned sparrow songs than to others. Hypothesis 2 is a proximate hypothesis. specifically regarding the immediate neural response-based causes of the females’ preferential response to particular song types. and justify your answer. and vice versa. 1. 4 . and keep your answers closely focused on what the question is asking. whether hypothesis 1 is true or false has no bearing on whether hypothesis 2 is likely to be true or false. Hypothesis 1 is an ultimate hypothesis. Woodland great tits sing songs with more high frequency elements in them than do forest great tits. Sounds that propagate better would lead to more reliable responses from conspecifics. One hypothesis that could explain this difference is that the forest and woodland environments differentially affect the propagation of sounds of different pitch and this leads to selection favoring individuals who produce the type of song that works best for communication in their particular habitat. This would be an ultimate hypothesis because it addresses the fitness consequences of variation in the behavior. Syringial muscles also need not be illustrated. and what makes “two voices” possible.Name:______________________________________________ 3. how air flow is involved. but should be mentioned as part of the verbal description of how the organ produces sound. A complete answer will make clear exactly what needs to occur in order for sounds to be produced. and the air passing through the partially-blocked right bronchus produces vibration in the right medial and lateral labia. and then describe in words how sound is produced by this organ. the left and right medial and lateral labia. with the sound being produced by the left labia. label the key anatomical components that are important for sound production and regulation. how different parts of the syrinx are involved in production of sounds of different pitches. Air sacs need not be illustrated. but should be mentioned as the source of the pressure that causes air to flow out through the bronchi to produce sound. In words. and the cartilage on each side that swings in to push each lateral labium into the bronchus. how muscular control of the syrinx affects sound production. then the left bronchus is blocked entirely. If only a low sound is to be produced. Signature: ______________________________________________________________ 5 . Sketch should illustrate the trachea and bronchi. then two separate sounds (two “voices”) can be produced simultaneously. If only a high sound is to be produced. pressure in the airsacs forces air outward through the bronchi. and then selective contraction of syringial muscles causes the left and right bronchi to be either partially or completely occluded by the cartilage swinging in and pushing the lateral labia into the air passage. producing the high pitched sound. the converse happens. (10 pts) Sketch the syrinx of a songbird. what specific parts are thought to actually produce the sounds. I hereby give the instructors of NPB 102 my permission to return my exam to me by leaving it in the hall boxes in Briggs Hall. If both bronchi are only partially constricted. referring to your figure.