Actively engaging students in lecture has been shown to increase learning gains. To create time for active learning without displacing content we used two strategies for introducing material before class in a large introductory biology course. Four to five slides from 2007/8 were removed from each of three lectures in 2009 and the information introduced in preclass worksheets or narrated PowerPoint videos. In class, time created by shifting lecture material to learn before lecture (LBL) assignments was used to engage students in application of their new knowledge. Learning was evaluated by comparing student performance in 2009 versus 2007/8 on LBL-related question pairs, matched by level and format. The percentage of students who correctly answered five of six LBL-related exam questions was significantly higher (p < 0.001) in 2009 versus 2007/8. The mean increase in performance was 21% across the six LBL-related questions compared with <3% on all non-LBL exam questions. The worksheet and video LBL formats were equally effective based on a cross-over experimental design. These results demonstrate that LBLs combined with interactive exercises can be implemented incrementally and result in significant increases in learning gains in large introductory biology classes.

A trait typical of parrots, but rare in other groups of birds, is the acquisition of new learned calls (acquired by copying conspecifics) throughout an individual's lifetime. The significance of this distinctive psittacid trait is not understood. In budgerigars, females preferentially affiliate with unfamiliar males whose contact calls resemble their own during brief dyadic choice trials; also, in forced‐pair situations, contact call similarity of members of pairs increases as a result of a male tendency to imitate his mate's call type. The functions of budgerigar call imitation and preference for pre‐pairing similarity are currently unknown. Moreover, as budgerigar pair formation occurs over a span of days or weeks, it is important to determine whether birds in breeding colonies assort and proceed to breed on the basis of pre‐pairing contact call similarity, and whether high levels of call similarity are maintained after pair formation is complete. To explore these questions, we recorded contact calls of male and female budgerigars before and after they were placed into an aviary equipped for breeding. As predicted, birds paired assortatively based on pre‐pairing call similarity. Once birds had paired, their calls converged further in acoustic structure, as previous work had led us to expect. However, after eggs were laid and the males began to feed their mates, the calls of mated birds diverged, suggesting that there might be some cost to maintenance of shared calls. Male care‐giving correlated with the degree to which his pre‐pairing calls resembled those of his mate, but not with the similarity achieved through convergence. These results suggest that female budgerigars may use a male's pre‐pairing call similarity as a predictor of paternal investment. The questions of why such similarity predicts male care‐giving, and why calls converge following initial pairing activities, require further work.

Parrots comprise one of the several taxa in which life‐long learning of new vocal signals used in intraspecific communication is known to occur routinely. The functions and evolutionary bases of this ability are largely unknown. In the budgerigar (Melopsittacus undulatus), males typically imitate their partner’s contact call type during pair formation. However, a female’s initial choice among unfamiliar males is not based on their production of her call type, because birds without prior social contact rarely produce the same call type. Here, we demonstrate that female budgerigars prefer unfamiliar males with calls that are similar to their own, as measured by spectrogram cross‐correlation, but which are not imitations. This was shown by training females via operant conditioning to control access to movies of courting males and by systematically varying the audio tracks of these movies. Females learned this task easily and interacted with virtual males as if they were real. This methodology will be useful for exploring functions and mechanisms of social communication, because it eliminates the confounding impact of short‐term changes in a stimulus individual’s behavior on a test individual’s response. Our results suggest that the neuroplastic vocal abilities of budgerigars, and perhaps other parrots, have been shaped by sexual selection.

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