An Analysis of the full song of five free-living urban European Blackbirds (Turdus merula); a network approach.

Mapping Intimacies ◽

10.1101/505206 ◽

2018 ◽

Author(s):

Koenraad Kortmulder

Keyword(s):

Breeding Season ◽

Network Theory ◽

Network Approach ◽

Considerable Part ◽

Free Living ◽

Song Repertoire ◽

Turdus Merula ◽

Repeated Retrieval ◽

Existing Structure ◽

Song Repertoires

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.

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Fitness Correlates of Song Repertoire Size in Free‐Living Song Sparrows (Melospiza melodia)

The American Naturalist ◽

10.1086/428299 ◽

2005 ◽

Vol 165 (3) ◽

pp. 299-310 ◽

Cited By ~ 51

Author(s):

Jane M. Reid ◽

Peter Arcese ◽

Alice L. E. V. Cassidy ◽

Sara M. Hiebert ◽

James N. M. Smith ◽

...

Keyword(s):

Melospiza Melodia ◽

Repertoire Size ◽

Free Living ◽

Song Repertoire ◽

Song Sparrows

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Understanding the Implementation of IT Governance Arrangements and IT Infrastructure Using Actor Network Theory

International Journal of Actor-Network Theory and Technological Innovation ◽

10.4018/ijantti.2016040104 ◽

2016 ◽

Vol 8 (2) ◽

pp. 44-55

Author(s):

Hafizah Mohamad Hsbollah ◽

Alan Simon ◽

Nick Letch

Keyword(s):

Information Systems ◽

Network Theory ◽

It Governance ◽

Actor Network Theory ◽

Global Network ◽

It Infrastructure ◽

Network Approach ◽

Actor Network ◽

The Relationship ◽

Governance Arrangements

The implementation of IT governance (ITG) arrangements and its relationship to IT infrastructure has not received much attention in either the ITG or the information systems (IS) literature. Based on the premise that the foundation on which ITG is implemented lies in the interaction between ITG arrangements of structures, processes and relational mechanisms and IT infrastructure, the authors present a discussion of how actor network theory (ANT) can be used as an overarching theoretical framework of explanation. The authors propose a model of ITG implementation and discuss how ANT, in particular the local/global network approach, can be applied to understand the relationship that exists between ITG arrangements and IT infrastructure.

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Clusters as a Mechanism of Sharing Knowledge and Innovation: Case Study from a Network Approach

Global Business Review ◽

10.1177/0972150920957270 ◽

2020 ◽

pp. 097215092095727

Author(s):

Mário Franco ◽

Lurdes Esteves ◽

Margarida Rodrigues

Keyword(s):

Qualitative Research ◽

Content Analysis ◽

Network Theory ◽

Industrial Cluster ◽

Network Approach ◽

Organizational Relationships ◽

Mutual Help ◽

Innovation Activities ◽

Family Enterprises

Following a network approach, this study aims to understand the potential of inter-organizational relationships in clusters for sharing knowledge and innovation. To this end, qualitative research of an exploratory nature was undertaken, with the information being gathered through interviews with owners and managers of small and medium-sized family enterprises belonging to an agro-industrial cluster in Portugal. Through content analysis, the results obtained showed that clustering 1 promotes the publicizing and internationalization of products and has an impact on small and medium-sized enterprises’ (SME) results. The importance of the cluster’s action regarding innovation was also confirmed, and so was its potential as a catalyst for the sharing of knowledge. Business-people’s attitude and relational competences, particularly trust, mutual help and having an open mind, were found to be essential factors for successful network functioning and the clustering process. Therefore, this study contributes to the developing existing theory by analysing clustering as inter-organizational networks of sharing knowledge and innovation activities in the light of the network theory and its association with resource-based and knowledge-sharing theories.

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Diurnal cycle of Isospora spp. oocyst shedding in Eurasian blackbirds (Turdus merula)

Canadian Journal of Zoology ◽

10.1139/z04-054 ◽

2004 ◽

Vol 82 (5) ◽

pp. 764-768 ◽

Cited By ~ 17

Author(s):

Katharina Misof

Keyword(s):

Population Dynamics ◽

Diurnal Cycle ◽

Bird Species ◽

Free Living ◽

Turdus Merula ◽

Coccidian Oocyst ◽

Diurnal Fluctuations ◽

Evolutionary Aspects ◽

Practical Implications

Diurnal fluctuations in the appearance of parasites have been recognized for more than 60 years but have been largely ignored in studies examining the role of parasites in connection with evolutionary aspects of behaviour, ecology, and population dynamics. The disregard of diurnal fluctuations, however, can influence the reliability and interpretation of data. I examined shedding of Isospora spp. oocysts in faeces of naturally infected, free-living Eurasian blackbirds (Turdus merula L., 1758). Adult birds and nestlings shed coccidian oocysts (Isospora spp.) predominantly in the afternoon. The results are in agreement with earlier studies on coccidian oocyst shedding in other bird species. They are discussed with regard to these studies and to practical implications for future investigators in this field.

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

Behaviour ◽

10.1163/156853900501881 ◽

2000 ◽

Vol 137 (1) ◽

pp. 75-92 ◽

Cited By ~ 2

Author(s):

◽

Keyword(s):

Pca Analysis ◽

Repertoire Size ◽

Free Living ◽

Similar Correlation ◽

Sturnella Magna ◽

Different Types ◽

Song Types ◽

Song Repertoires

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.

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The Ecology of Rattus lutreolus III*. The Rise and Fall of a Commensal Population

Wildlife Research ◽

10.1071/wr9800199 ◽

1980 ◽

Vol 7 (2) ◽

pp. 199 ◽

Cited By ~ 1

Author(s):

RW Braithwaite

Keyword(s):

Body Size ◽

Habitat Use ◽

Breeding Season ◽

Sexual Maturity ◽

Free Living ◽

Mark Recapture

A free-living population of R. lutreolus living in and around the zoo enclosures of the Sir Colin MacKenzie Fauna Park at Healesville was studied for 27 months by use of mark-recapture trapping techniques. The demography of this population is compared with that of a natural heathland population. The breeding season was 2-3 months longer, growth of juveniles was more rapid, sexual maturity earlier, minimum survival shorter, body size larger, and habitat use less restricted in the commensal population. The evolution of the population and its decline are discussed.

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Male quality and song repertoires in western meadowlarks (Sturnella neglecta)

Canadian Journal of Zoology ◽

10.1139/z93-140 ◽

1993 ◽

Vol 71 (5) ◽

pp. 1059-1061 ◽

Cited By ~ 10

Author(s):

Andrew G. Horn ◽

Thomas E. Dickinson ◽

J. Bruce Falls

Keyword(s):

Reproductive Success ◽

Wing Length ◽

Territory Size ◽

Male Quality ◽

Repertoire Size ◽

Song Repertoire ◽

Signalling System ◽

The Relationship ◽

Sturnella Neglecta ◽

Song Repertoires

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.

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