SONG CLUSTERING BY MEADOWLARKS: IS IT RELATED TO REPERTOIRE SIZE?

Behaviour ◽  
2000 ◽  
Vol 137 (1) ◽  
pp. 75-92 ◽  
Author(s):  
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AbstractSome birds with song repertoires sequentially associate (or cluster) songs of different types. That is, certain song types may occur together repeatedly, even on different days. We determined whether clustering of meadowlark songs correlated with repertoire size. We also tested whether clustered songs reflect either their structural similarities, or dissimilarities. Our data were obtained from recordings of free-living individuals of two meadowlark species, eastern, Sturnella magna , and western, S. neglecta . Eastern meadowlarks have approximately 10 times more song types per bird than do westerns. Therefore, if clustering is related to repertoire size, we predicted that there should be (1) proportionately more song clusters in eastern meadowlarks than in westerns, and (2) a similar correlation across individual birds within a species, especially so in easterns, which have a broader range of repertoire sizes. All 14 easterns examined showed clusters whereas only 5 of 11 westerns did so, and the easterns had proportionately more per bird. Many of the same clusters occurred in different recordings of individual easterns. In easterns, the extent of clustering as measured by a PCA analysis correlated strongly with estimated repertoire size. Clustered songs were neither more similar in structure, nor less so, than randomly-paired songs.

The Auk ◽  
2000 ◽  
Vol 117 (4) ◽  
pp. 936-942 ◽  
Author(s):  
Susan Peters ◽  
William A. Searcy ◽  
Michael D. Beecher ◽  
Stephen Nowicki

Abstract We asked whether geographic variation exists in the complexity of song repertoires in Song Sparrows (Melospiza melodia) by quantitatively comparing four measures of repertoire organization across four geographically distant populations: (1) repertoire size (the number of distinct song types), (2) the number of “minimal units of production” per repertoire, (3) mean similarity among variants of the same song type (“within-type” similarity), and (4) mean similarity among song types in a repertoire (“between-type” similarity). We found significant geographic differences among populations in three of these four measures, with mean similarity among song types being the exception. In general, relatively sedentary populations in North Carolina and Washington were more similar to each other than to migratory populations in Pennsylvania and Maine. Contrary to our expectation based on prior interspecific analyses of variation in repertoire complexity, the relatively sedentary populations in our sample had more complex repertoires than did the more migratory populations. The origin and functional significance of population differences in repertoire complexity in this species remain uncertain.


Behaviour ◽  
1983 ◽  
Vol 87 (3-4) ◽  
pp. 256-269 ◽  
Author(s):  
S.M. Dawson ◽  
P.F. Jenkins

AbstractThe aim of this investigation was to determine to what extent song repertoires and singing behaviour of chaffinches (Fringilla coelebs) evolved as a means by which resident birds deceive intruders into overestimating the density of residents, making the area appear less suitable for settlement. (1) The chaffinches studied did not show a significant tendency to change song posts synchronously any more than would be expected by chance. (2) Approximately 90% of song type/song post changes were asynchronous. (3) Half of the birds did not repeat their song types with equal frequency, nor did they distribute their singing effort evenly over all the song posts. (4) The degree of similarity between song types in the same repertoire and the degree of similarity between song types from different individuals were not found to be significantly different. (5) No correlation between song rate and repertoire size was found, but it was concluded that seasonal biases strongly restricted this facet of the investigation. On the basis of these findings it is concluded that the evolution of repertoires and singing behaviour in chaffinches seems unlikely to have occurred in conformity with the Beau Geste hypothesis.


2005 ◽  
Vol 165 (3) ◽  
pp. 299-310 ◽  
Author(s):  
Jane M. Reid ◽  
Peter Arcese ◽  
Alice L. E. V. Cassidy ◽  
Sara M. Hiebert ◽  
James N. M. Smith ◽  
...  

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5775 ◽  
Author(s):  
Yanxiang Yang ◽  
Moritz Schumann ◽  
Shenglong Le ◽  
Shulin Cheng

Background Objective assessments of sedentary behavior and physical activity (PA) by using accelerometer-based wearable devices are ever expanding, given their importance in the global context of health maintenance. This study aimed to determine the reliability and validity of a new accelerometer-based analyzer (Fibion) for detecting different PAs and estimating energy expenditure (EE) during a simulated free-living day. Methods The study consisted of two parts: a reliability (n = 18) and a validity (n = 19) test. Reliability was assessed by a 45 min protocol of repeated sitting, standing, and walking (i.e., 3 × 15 min, repeated twice), using both Fibion and ActiGraph. Validity was assessed by a 12 h continuous sequence tasks of different types (sitting, standing, walking, and cycling) and intensities (light [LPA], moderate [MPA], and vigorous [VPA]) of PA. Two Fibion devices were worn on the thigh (FT) and in the pocket (FP), respectively and were compared with criteria measures, such as direct observation (criterion 1) and oxygen consumption by a portable gas analyzer, K4b2 (criterion 2). Results FT (intra-class correlation coefficients (ICCs): 0.687–0.806) provided similar reliability as the Actigraph (ICCs: 0.661–0.806) for EE estimation. However, the measurement error (ME) of FT compared to the actual time records indicated an underestimation of duration by 5.1 ± 1.2%, 3.8 ± 0.3% and 14.9 ± 2.6% during sitting, walking, and standing, respectively. During the validity test, FT but not FP showed a moderate agreement but lager variance with the criteria (1 and 2) in assessing duration of sitting, long sitting, LPA, MPA, and VPA (p > 0.05, ICCs: 0.071–0.537), as well as for EE estimation of standing, LPA, MPA, and VPA (p > 0.05, ICCs: 0.673–0.894). Conclusions FT provided similar reliability to that of the Actigraph. However, low correlations between subsequent measurements of both devices indicated large random MEs, which were somewhat diminished during the simulated 12 h real-life test. Furthermore, FT may accurately determine the types, intensities of PA and EE during prolonged periods with substantial changes in postures, indicating that the location of the accelerometer is essential. Further study with a large cohort is needed to confirm the usability of Fibion, especially for detecting the low-intensity PAs.


The Condor ◽  
2006 ◽  
Vol 108 (2) ◽  
pp. 326-335 ◽  
Author(s):  
David M. Logue

Abstract In many duet-singing songbirds, paired birds combine their song types nonrandomly to form duet songs. Several different behavioral mechanisms could generate nonrandom song type associations in duets. I tested female Black-bellied Wrens (Thryothorus fasciatoventris) for one such mechanism: adherence to a set of rules linking female response songs to male stimulus songs. I call this set of rules a “duet code.” Duets of free-living Black-bellied Wrens were recorded in 2001 and 2002. In 2003 I returned to the same territories and played the male song types from the recorded duets. Females answered male song stimuli as if duetting with the playback speaker. Although the known repertoires of females averaged 8.4 song types, each female sang only a single song type in response to each male song type. Random answering could not account for this pattern, supporting the hypothesis that females abide by duet codes. Females that were still paired with their mates from 2001–2002 answered 100% of their mate's songs with the same song types they had used previously, demonstrating that codes are stable over time. In contrast, females that were new to a territory answered an average of only 18% of their mate's song types with the same song type as the previous female, indicating that duet codes are individually distinctive. Duet participation by female Black-bellied Wrens represents a special kind of animal communication, in which discrete vocal signals consistently elicit discrete vocal responses according to an individually distinctive set of rules.


The Condor ◽  
2001 ◽  
Vol 103 (4) ◽  
pp. 855-861
Author(s):  
Donald E. Kroodsma ◽  
Krista Wilda ◽  
Viviana Salas ◽  
Roldan Muradian

Abstract Evidence from two Cistothorus wrens (C. palustris, C. platensis) has suggested that repertoire size increases with population density and that song imitators are more likely to be site faithful than are song improvisers. We tested these two ideas on a third species, C. meridae, an endemic to the Venezuelan Andes. Of the three Cistothorus wrens, song repertoire sizes of male Mérida Wrens are the smallest, ranging from 18 to 27 song types per male; Mérida Wrens are also most likely to repeat each type several times before switching to a new type. Density of Mérida Wrens was also lowest, from 0.4 to 2.0 territories per 10 ha. These wrens are highly site faithful, with marked microgeographic song variation. Female Mérida Wrens also sing. Overall, data from the Mérida Wren support the ideas that, among Cistothorus wrens, song repertoire sizes increase with population density and site faithfulness promotes song imitation. Variación en el Canto en Cistothorus, con Énfasis en C. meridae Resumen. La evidencia proveniente de dos especies del género Cistothorus (C. palustris, C. platensis) sugiere que el tamaño del repertorio aumenta con la densidad poblacional y que los imitadores de cantos tienen una mayor probabilidad de ser territoriales que los que improvisan. Estas dos ideas fueron probadas en una tercera especie endémica de los Andes venezolanos, C. meridae. El tamaño del repertorio del canto de esta especie, con 18 a 27 tipos de canto por macho, es el más pequeño de estas tres especies. C. meridae también tiene una mayor probabilidad de repetir cada tipo de canto varias veces antes de cambiar a un tipo nuevo. La densidad de C. meridae también fue la menor, con 0.4 a 2.0 territorios por cada 10 hectáreas. C. meridae es muy territorial, con una marcada variación microgeográfica en las cantos. Las hembras de esta especie también cantan. En resumen, estos datos apoyan las ideas de que en el género Cistothorus, el tamaño del repertorio del canto aumenta con la densidad poblacional y que la territorialidad promueve la imitación de cantos.


1993 ◽  
Vol 71 (5) ◽  
pp. 1059-1061 ◽  
Author(s):  
Andrew G. Horn ◽  
Thomas E. Dickinson ◽  
J. Bruce Falls

The relationship between song repertoire size and measures of male quality and reproductive success was examined in a Manitoba population of western meadowlarks (Sturnella neglecta). Repertoire size correlated positively with the singer's wing length but not with mass or territory size. Males with larger repertoires tended to pair earlier and males with higher pairing success had larger repertoires. Repertoire size correlated positively with fledging success independently of pairing success. As suggested for other species, repertoire size might serve as a signal to females of male quality. We suggest mechanisms by which this signalling system is maintained.


Behaviour ◽  
1991 ◽  
Vol 116 (3-4) ◽  
pp. 210-238 ◽  
Author(s):  
Rudolf Frans Verheyen ◽  
Marcel Eens ◽  
Rianne Pinxten

AbstractThis study had two aims. First, we looked at individual differences in song characteristics between males of the European starling, and we related song behaviour to factors such as male age, pairing date, polygyny and male breeding success. Second, we experimentally tested whether song has an effect on female mating decisions. 1. During the breeding season, male starlings sing a very long and complex song consisting of a rapid succession of large number of different song types. We observed marked differences between males in average song bout length (a song bout was defined as a period of at least five seconds of song containing no pauses larger than 1.5 seconds) and in song repertoire size. Average song bout lengths ranged from 16 to 35 seconds. The individual repertoire size ranged from 23 to 67 song types. Repertoire size and average song bout length were positively correlated. 2. Both in the field and in captivity, yearling males sang shorter average song bout lengths and had smaller repertoire sizes than older males. 3. Males singing longer average song bouts and having larger repertoire sizes attracted females for pairing before their rivals with shorter average song bouts and smaller repertoire sizes.


2018 ◽  
Author(s):  
Koenraad Kortmulder

Is the song repertoire of male blackbirds safe-guarded against loss of variability during the breeding season? In order to answer this question the repertoires of five males were analysed from the viewpoint of network theory. In four of the five males a strong coherence of the repertoire was found to exist in anastomoses between strophe types, same elements being reached from different beginnings. The succession of strophe types in song sessions betrayed a mixture of relatively predictable cycles and chaotic connections. The former should facilitate repeated retrieval of a considerable part of the repertoire, while the chaotic component keeps the whole repertoire readily accessible from any point in a singing session. The same mixture may be considered optimal for binding the attention of conspecific listeners. It is concluded that the existing structure of blackbird song repertoires is favourable for the conservation of its richness, but it is as yet uncertain whether this is due to evolutionary (i.c. sexual) adaptation.


2019 ◽  
Vol 15 (1) ◽  
pp. 20180607 ◽  
Author(s):  
Ghazal Rashidi ◽  
Elizabeth A. Ostrowski

Phagocytes are cells that pursue, engulf and kill bacteria. They include macrophages and neutrophils of the mammalian immune system, as well as free-living amoebae that hunt and engulf bacteria for food. Phagocytosis can result in diverse outcomes, ranging from sustenance to infection and colonization by either pathogens or beneficial symbionts—and thus, discrimination may be necessary to seek out good bacteria while avoiding bad ones. Here we tested whether the soil amoeba Dictyostelium discoideum can discriminate among different types of bacteria using behavioural assays where amoebae were presented with paired choices of different bacteria. We observed variation in the extent to which the amoebae pursued different types of bacteria, as well as preferential migration towards Gram-negative compared with Gram-positive bacteria. Response profiles were similar for amoebae that originated from different geographical locations, suggesting that chase preference is conserved across much of the species range. While prior work has demonstrated that bacteria use chemotaxis to seek out amoebae they colonize, our work suggests that the opposite also occurs—amoebae can preferentially direct themselves to particular bacteria in the environment. Preferential sensing and response may help to explain why some amoeba–bacteria associations are more common in nature than others.


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