02109nas a2200253   4500008004100000022001400041245006900055210006500124260001600189520134000205653002301545653001201568653003001580653001301610653001501623653000901638100002201647700002201669700002301691700003101714700003101745700002401776856005501800       2018                        eng d  a2193-719200aThe buzz segment of Savannah sparrow song is a population marker0 abuzz segment of Savannah sparrow song is a population marker  cMar-12-20183 a<p>Different components of learned birdsongs change at different rates across generations, and the rate of change may correspond to the information carried by each component. To characterize the role of the buzz segment of Savannah sparrow songs, we examined recordings from southeastern Canada and the northeastern US and fully characterized buzz segments in songs recorded from two populations: one on Kent Island, NB, Canada and another in Williamstown, MA, USA. Buzzes varied geographically: Kent Island buzzes had higher mean frequencies and shorter pulse periods than Williamstown buzzes and the differences between the two populations persisted over time. Population-specific buzz characteristics also appeared to be resistant to change. Variants appeared on Kent Island in the late 1980s and were learned by some younger birds; however, these buzz variants disappeared by 2011. We conducted a playback experiment and found that males from both populations had longer responses to local buzzes. Therefore, buzz structure varies geographically; population characteristics of the buzz persist through time despite the introduction of variant forms; and territorial males discriminate between buzzes from different populations. The learned buzz segment of the song may thus serve as a population marker for Savannah sparrows.</p>
10aCultural evolution10adialect10aPasserculus sandwichensis10aplayback10aPopulation10asong1 aWilliams, Heather1 aRobins, Clint, W.1 aNewman, Amy, E. M.1 aFreeman-Gallant, Corey, R.1 aWheelwright, Nathaniel, T.1 aMennill, Daniel, J.  uhttp://link.springer.com/10.1007/s10336-018-1611-702429nas a2200253   4500008004100000245012300041210006900164260001600233300001400249490000800263520160100271653002601872653002501898653003401923653002201957653001501979100002001994700002702014700002302041700001702064700002402081700001502105856005502120       2018                        eng d00aQuiet violence: Savannah Sparrows respond to playback-simulated rivals using low-amplitude songs as aggressive signals0 aQuiet violence Savannah Sparrows respond to playbacksimulated ri  cJan-10-2018  a724 - 7320 v1243 a<p>When animals compete over resources such as breeding territories, they often use signals to communicate their aggressive intentions. By studying which signals are associated with aggressive interactions, we gain a deeper appreciation of animal behaviour. We studied aggressive signalling in male Savannah Sparrows, Passerculus sandwichensis, focusing on signals that precede physical attack against territorial intruders. We simulated intruders using song playback and taxidermic models, and we determined which behaviours were associated with physical attack. Previous studies that have used this approach suggest that many species produce songs of dramatically lower amplitude, or &ldquo;soft songs,&rdquo; as signals of aggressive intention. Savannah Sparrows, however, are not known to produce soft songs, and therefore, they provided an interesting system for testing signals that predict attack. Of 93 playback subjects, 23 males attacked the simulated intruder and 70 did not. To our surprise, Savannah Sparrows produced soft songs, and the number of soft songs was a significant predictor of attack on the simulated intruder. Birds also showed a nonsignificant tendency to produce more &ldquo;chip&rdquo; calls prior to attack on the simulated intruder, whereas three other measured behaviours (aggressive calls, wing waving and passes over the model) did not predict attack. Our study contributes to the growing body of research on aggressive territorial signals and reveals that soft song is an even more widespread signal of aggression in songbirds than previously recognized.</p>
10aaggressive signalling10aanimal communication10alow‐amplitude vocalizations10aSavannah Sparrows10asoft songs1 aMoran, Ines, G.1 aDoucet, Stéphanie, M.1 aNewman, Amy, E. M.1 aNorris, Ryan1 aMennill, Daniel, J.1 aKoenig, W.  uhttp://doi.wiley.com/10.1111/eth.2018.124.issue-10