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Spectral analysis of sounds of Saxicoloides fulicata (Indian robin)

100%

Rajashekhar M., Vijaykumar K.

International Letters of Natural Sciences

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2015

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tom 45

The present study focused on recordings of sounds of Saxicoloides fulicata (Indian robin) from Kalaburagi distract, Karnataka state. The study was undertaken during the Many 2012 to April 2013. During the study period about 50 samples of sounds of Indian robin were recorded and spectral analysis was performed subjected to sound samples. the study results indicate that, three types of sounds were identified and with significant variations in their structural hierarchy with distinct high and low frequencies.

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Variety of song characteristics of the Common Rosefinch Erythrina erythrina in the Kostrzyn Valley in 2015

84%

Parapura A.

Kulon

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2018

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tom 23

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Sexual selection and the evolution of song in birds of the genus Acrocephalus

84%

Borowiec M., Lontkowski J.

Biological Bulletin of Poznań

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2000

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tom 37

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nr 1

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Does the song of the Wren Troglodytes troglodytes change with different environmental sounds?

67%

Colino-Rabanal V. J., Mendes S., Peris S. J., Pescador M.

Acta Ornithologica

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2016

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tom 51

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nr 1

Birds inhabiting urban areas have to deal with high levels of ambient noise. Some species show a certain song flexibility that enables them to reduce noise interferences in their communications. This vocal adjustment usually implies an increase in the minimum frequencies of songs. Since urban noise is mainly made up of low frequencies (about 2.5-3.5 kHz), song of species that sing at higher frequencies could be less susceptible to being masked by anthropogenic noise. This study explores whether such species also show any kind of adjustment to noisy environments. For this purpose, the spectral and temporal parameters (note duration, maximum and minimum frequency and diversity) of the song of the European Wren Troglodytes troglodytes were analysed in three different environments (urban, periurban and rural). To evaluate the impact of noise on the vocalizations, a specific acoustic descriptor of song variability was developed. Song variability increased along the urban noise gradient from rural to urban areas and the duration of notes decreased from rural to urban zones. Urban wrens developed more complex songs with higher frequencies and longer notes than their rural counterparts, whereas peri-urban birds occupied an intermediate position, although closer to urban ones in the length of notes. These changes could be associated with higher background noise levels, although other possible causes, such as the population density, could also explain them. Maximum frequencies were mostly outside the background noise range and differed among habitats, whereas lower frequencies unexpectedly did not differ among habitats. Our results suggest that differences in song parameters among species may lead to different mechanisms of vocal adjustment. Even in wrens, with high frequency vocalisation, interference with urban anthropogenic noise could show certain changes in their vocalizations.

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Evolution of beak size and song constraints in Neotropical seedeaters (Thraupidae: Sporophila)

67%

Porzio N. S., Repenning M., Fontana C. S.

Acta Ornithologica

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2018

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tom 53

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nr 2

Many traits influence birdsong diversity. Patterns observed in the acoustic parameters can be a result of morphological constraint and can also be explained by phylogenetic relationships. Understanding morphologic mechanisms that can act on song structure might account how they can catalyze speciation and how they evolve in lineages sort. We analyzed the evolution of beak volume and song constraints in "finch-like" species of Neotropical seedeaters. We tested if beak volume limits the song structure of territorial songs, based on differences in the beaks of 19 species from the genus Sporophila (Thraupidae, tanagers). We also tested (1) if body size constrained song structure, and (2) if beak volume and body size were related to each other. The relationship of song parameters (e.g. maximum and minimum frequencies, frequency bandwidth and note rate) to these two morphological variables was evaluated through an analysis which phylogenetic relations were controlled (PGLS), testing a null and Brownian model. To perform a faithful analysis between morphologic and acoustic parameters, our data was based on measurements of the beak and territorial song for each individual that we analyzed. None of the analyzed parameters was related to beak volume or body mass, and beak volume was not associated with body mass. Beak volume, note rate, and minimum frequency showed a phylogenetic signal. These results do not support the theoretically motivated prediction that beak size acts as a limit on song structure in oscine birds. The shape and variations of song in Sporophila tanagers (Seedeaters) may be a consequence of the species' phylogenetic history, since the seedeaters showed wide plasticity in many acoustic parameters, unrelated to their beak volume and body mass. Song structure was better explained by the evolutionary relationships among the species than by morphological constraints.

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Śpiew ptaków

59%

Domaniewski J.

Wszechświat

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1957

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nr 04

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Czy ptaki posługują się echolokacją?

59%

Byczkowska-Smyk W.

Wszechświat

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1957

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nr 03

Ograniczanie wyników

2 Acta Ornithologica

2 Wszechświat

1 Biological Bulletin of Poznań

1 International Letters of Natural Sciences

1 Kulon

1 Borowiec M.

1 Byczkowska-Smyk W.

1 Colino-Rabanal V. J.

1 Domaniewski J.

1 Fontana C. S.

1 Lontkowski J.

1 Mendes S.

1 Parapura A.

1 Peris S. J.

1 Pescador M.

1 Porzio N. S.

1 Rajashekhar M.

1 Repenning M.

1 Vijaykumar K.

2 2018

1 2016

1 2015

1 2000