Andrew York -- Chant

Melro-preto (Turdus merula)

UXÍA

A voadora e sua influência no desenvolvimento do canto

Como canaricultores de canto, e em particular do timbrado, uma vez independente a jovem ave tem como missão que todo o potencial genético que temos obtido através  dos cruzamentos se consolide num exemplar que execute a sua versão do material que temos disposto demarcado nas suas características únicas de dicção, voz e capacidade de improvisação. Como já se tem mencionado em outras "entradas" (assuntos) do blog, este curto ma a la vez crítico caminho a la cristalização do canto começa desde o dia que colocamos na gaiola o jovem e se fecha no dia em que o seu canto está estabelecido a nível "neuronal" (sistema nervoso).

O audio para educar-los deve funcionar desde o primeiro dia e ainda que o exemplar pareça indiferente ao mesmo, o seu cérebro está absorvendo cada giro ( gorjeio) que imediatamente irá começar a ensaiar a tropezones mediante o sistema de realimentação auditiva, é dizer, tratando de imita-lo e escutando a la vez que compara e faz ajustes em base a seu mecanismo de análise inato . É por isso que ele recalca em varias ocasiões que nos jovens devem de ter tempo de ócio, isto quer dizer dizer, sem escutar audios, tempo em qual devem ser capazes de efectuar um "repaso" (gorjeio sem identificação) em condições. Em particular quando a um exemplar o assediamos todo o dia com um audio ou outro mecanismo digital de ensinamentos cortamos as suas possibilidades independentemente  de que tenha aprendido, com segurança poderia tido alcançado mais. 

Temos uma responsabilidade muito grande como gestores dos nossos "aviários" em maximizar a potencialidade de cada exemplar e cada decisão que tomamos por pequena que seja ,terá impacto no resultado final. 

Os lideres

Uma vez alojado nos poleiros da gaiola, o jovem canário começa a interrelacionar-se com o seu novo grupo de canários, na qual se estabelecem prontamente Hierarquias que só compreenderemos através das horas de observação necessárias. Se consideramos o nosso sujeito S como o exemplar de baixa análises, este se não é mesmo líder estará primordialmente baixa de influências do exemplar líder L. 

O exemplar L é aquele que claramente marca uma diferença com o resto do grupo, mostra a directa e sinistra suas incipientes virtudes canoras visivelmente mas adiantado que o resto e possivelmente já aclarando giros (gorjeios) de forma prematura, em qualquer  discussão vem prestes a demonstrar que é ele que marca na pauta, a sua influencia opaca em grande medida o efeito do audio já que como sabemos um canário sempre está mas disposto a aprender de um congénere que de algum  mecanismo artificial.  

Como considerações devemos afinar muito bem o ouvido, já que o exemplar líder pode ser uma boa influencia se a sua execução é adequada em termos de repertório e modalidade de emissão. Infortunadamente  na maior parte dos casos não só ser assim, no meu caso particular tenho colocado um vídeo de um pássaro líder deste ano que está actuando como maestro indirecto dentro de uma gaiola.  Adicionalmente faço a observação que numa gaiola ou  voadora pode haver mais de um líder. 

Os Indiferentes

Podemos observar também a presença de uns exemplares indiferentes  que pode estar composto de fêmeas  passivas ou de outros exemplares machos que estão numa etapa primaria e que não afectará o nosso sujeito S.

Os defeituosos

Devemos extremar também as precauções ante la presença de exemplares nos lideres mas com defeitos apenas imperceptíveis já que estamos na etapa de "repassos" ( gorjeios indefinidos). Quando detectamos esta situação devemos actuar sem contemplações desterrando a estes exemplares de forma imediata. É também possível que o nosso exemplar defeituoso se encontre numa voadora muito próxima desde onde poderá dar uma nota com um limpo desenvolvimento do exemplar S.

O sistema de Audio

O Sistema de Audio é o nosso professor por excelência, sem erros (deliberados) de forma programada parece possível do objectivo final, se o audio é bom, carece de demasiada artificialidade e se assemelha ao canto de um canário real os factores principais de êxito estejam cimentados.

Outras Aves 

A presença de outras aves dentro e fora do nosso aviário não é um factor para desapreciar, no meu caso no meu jardim é assediado ao amanhecer por pequenas aves conhecidas como "ch" que possuem gorjeios de extraordinária beleza mas que adornam com notas de "reñidero" fazendo em perigo a aprendizagem. Pegas, melros pardais de telhado também aparecem em grupo na busca de restos de sementes saltando de um arbusto para outro. Todas estas aves podem afectar o nosso  objectivo. Neste caso a minha recomendação é o uso de barreiras acústicas que neutralizem os sons provenientes destas aves.

O meio ambiente e os sons mecânicos

Recordo com "saudade" a historia que repetia o desaparecido Don  Guilarte  que nunca duvidei  sobre um jovem canário que lhe aprendeu o som da  máquina de escrever já que costumava usar próxima da voadora dos jovens aves. Os canários jovens em certos períodos que denominamos críticos são como esponjas capazes de absorver e abstrair-se e focar-se caprichosamente em alguns sons que como afirmava outro grande criador de timbrado, Don Álvaro Guillén: são como os meninos quando começam a ir ao colégio, o que eles geralmente aprendem primeiro são os "palavrões " .

Em conclusão que queria mostrar o panorama ao que se enfrentam os jovens timbrados apenas se tornam independentes , são muitos os factores que podem influenciar negativamente e a nossa melhor arma é gratuita: 
Na observação e na escuta dos incipientes "repassos" a fim de acabar de forma determinante qualquer obstáculo no caminho ao desenvolvimento pleno da potencialidade de nossos exemplares.


http://timbradospanama.blogspot.pt/2015/06/la-voladera-y-su-influencia-en-el.html?spref=fb timbrados panama

traduzido Pedro Boavida

Slowik / Nightingale/ Ruiseñor/ Rouxinol

Nightingale / Rouxinol / Ruiseñor

Travis Pratt

Pássaros reagem ao seu canto da mesma forma que humanos reagem à música

Estudo com pardal-de-garganta-branca está publicado
na «Frontiers of Evolutionary Neuroscience»

Pardal-de-garganta-branca

Ao escutar o canto dos seus pares, um pássaro por experimentar algumas das mesmas emoções que sente um humano quando ouve música. 

Esta é a conclusão de um estudo realizado com o pardal-de-garganta-branca (Zonotrichia albicollis) e publicado agora na revista «Frontiers of 

Evolutionary Neuroscience».

“O mesmo sistema neuronal de recompensa é activado nas fêmeas em fase de reprodução quando escutam um macho e nas pessoas quando ouvem música de que gostam”, explica Sarah Earp, que dirigiu a investigação como estudante da Universidade de Emory, EUA.

Os machos têm uma resposta diferente quando escutam o cantar de outro macho, semelhante à das pessoas quando ouvem música dissonante ou desagradável.

 

Este estudo é o primeiro a comparar as respostas neuronais dos ouvintes e enquadra-se na alargada discussão que tem sido levado a cabo por investigadores sobre a ligação entre o canto dos pássaros e a música.

“Desde Darwin que os cientistas se têm interrogado se o canto dos pássaros e a música podem servir para fins semelhantes e se têm o mesmo percurso evolutivo”, diz Earp.

Artigo: Birdsong: is it music to their ears?

in Ciência Hoje 

Birdsong: is it music to their ears?

Since the time of Darwin, biologists have wondered whether birdsong and music may serve similar purposes or have the same evolutionary precursors. Most attempts to compare song with music have focused on the qualities of the sounds themselves, such as melody and rhythm. Song is a signal, however, and as such its meaning is tied inextricably to the response of the receiver. Imaging studies in humans have revealed that hearing music induces neural responses in the mesolimbic reward pathway. In this study, we tested whether the homologous pathway responds in songbirds exposed to conspecific song. We played male song to laboratory-housed white-throated sparrows, and immunolabeled the immediate early gene product Egr-1 in each region of the reward pathway that has a clear or putative homologue in humans. We found that the responses, and how well they mirrored those of humans listening to music, depended on sex and endocrine state. In females with breeding-typical plasma levels of estradiol, all of the regions of the mesolimbic reward pathway that respond to music in humans responded to song. In males, we saw responses in the amygdala but not the nucleus accumbens – similar to the pattern reported in humans listening to unpleasant music. The shared responses in the evolutionarily ancient mesolimbic reward system suggest that birdsong and music engage the same neuroaffective mechanisms in the intended listeners.

Introduction

Ornithologists and musicians alike have long contemplated whether the song of birds might somehow be classified as “music.” The question can be approached from a variety of angles, each of which produces a somewhat different answer. Researchers have asked, for example, whether birdsong and music share evolutionary precursors or functions (Darwin, 1871; Catchpole and Slater, 1995; Miller, 2001), tonal variation or rhythm (Dobson and Lemon, 1977; Slater, 2001; Baptista and Keister, 2005; Araya-Salas, 2012), or organization (Marler, 2001), and whether, like music, birdsong is creative (Marler, 2001; Hartshorne, 2008). Whether any particular species of songbird has music-like song depends on the parameter measured and the type of analysis employed.

Birdsong, hereafter referred to as song, is a signal; it has a sender and a receiver. Ultimately, a signal’s effect on the receiver, not its structure, dictates its meaning and function (reviewed by Scott-Phillips, 2008). When comparing song and music, it may therefore be informative to ask about the receiver’s response and subjective experience. Human listeners find music rewarding; they will approach it and work to hear it. Songbirds of many species likewise show a phonotaxic response to conspecific song. Female pied flycatchers (Ficedula albicollis) and European starlings (Sturnus vulgaris) approach and enter nest boxes containing speakers playing male song (Eriksson and Wallin, 1986; Gentner and Hulse, 2000), and female zebra finches (Taeniopygia guttata) will peck a key to hear male song (Riebel, 2000). Young male zebra finches who are learning to sing will also peck to hear song (Adret, 1993), but in general, a phonotaxic effect of song is less pronounced in male songbirds than in females (Dobson and Petrinovich, 1973; Stevenson-Hinde and Roper, 1975).

Measuring behavioral responses is but one way to assess the effects of a signal on the receiver. Over the past decade, neuroimaging studies have identified at least 20 different brain regions that show altered BOLD or PET responses during music listening. Some of the most commonly reported responses, particularly to music that is pleasurable to the listener, are those of the mesolimbic reward system. This system consists of the ventral tegmental area (VTA) and its dopaminergic projections to several regions of the forebrain, for example the nucleus accumbens (nAc) in the ventral striatum. 

Release of dopamine in nAc occurs at precisely the time that intensely pleasurable autonomic responses, or “chills,” are experienced during music listening (Salimpoor et al., 2011). Although the release itself may not itself cause the experience of reward, it indicates that the stimulus is associated with reward (reviewed by Wise, 2004). Also included in the reward system are the dorsal striatum (e.g., caudate nucleus in humans), the heavily interconnected amygdala and hippocampus (Hp), and the prefrontal cortex. Each of these regions have been shown in multiple human imaging studies to respond to music with BOLD or PET responses (Blood and Zatorre, 2001; Koelsch et al., 2006; Mitterschiffthaler et al., 2007; Montag et al., 2011; Pereira et al., 2011; Salimpoor et al., 2011).

In this study we looked for neural responses to song in the avian homologues of music-responsive brain regions. Functional MRI can be used in songbirds listening to song (Van Meir et al., 2005; Boumans et al., 2007), but to date those analyses have focused primarily on the major auditory areas. The nAc and other areas known to respond to music in humans are difficult to study using this technique in songbirds, primarily because of their small size. Neural responses to stimuli can be more readily studied in birds by mapping the expression of immediate early genes (IEGs) such as Fos and Egr-1. In such studies, a stimulus is presented to an animal and the brain harvested 60–90 min later. The protein products of IEGs can then be labeled in fixed brain sections using immunohistochemistry, which provides cellular resolution. 

Dubbed the “genomic action potential” (Clayton, 2000), the IEG response indicates that a neuron has begun to respond to a stimulus with new protein synthesis related to synaptic remodeling. Although the IEG and BOLD responses make use of different underlying molecular mechanisms, there is good agreement between results obtained by both methods (Lazovic et al., 2005; Stark et al., 2006). In songbirds, for example, hearing song induces robust Egr-1 and BOLD responses in the auditory forebrain (Mello et al., 1992; Gentner et al., 2001; Van Meir et al., 2005; Boumans et al., 2007). Egr-1 is particularly useful in the study of reward because it appears to play an active role in the reward process. In rodents, Egr-1 is induced in the reward pathway by drugs such as methamphetamine, morphine, nicotine, or cocaine (reviewed by Girault et al., 2007). 

Blockade of Egr-1 prevents conditioned behavioral responses to these drugs, suggesting that Egr-1 not only marks neuronal responses to reward but is required for the acquisition of reward-reinforced behaviors.

In this study, we used Egr-1 as a marker to map and quantify neural responses in the mesolimbic reward system in male and female white-throated sparrows (Zonotrichia albicollis) listening to conspecific male song. This species sings a particularly musical-sounding song (Saunders, 1959) with heavy use of whistles with a sustained pitch (Dobson and Lemon, 1977). During the non-breeding season, song is used by both sexes to establish and maintain dominance relationships (reviewed by Maney and Goodson, 2011). During the breeding season, however, the message contained in song differs for male and female listeners. A female listening to male song is almost certainly being courted, whereas a male is being challenged by a territory holder or intruder. Song is therefore expected to have a more positive valence for females than for males. We predicted that neural responses to song in the females would resemble that of humans listening to liked music, whereas the pattern in the males would not.

The valence of song may be affected also by endocrine state. In Zonotrichia sparrows, females give a courtship display in response to song only when their plasma estradiol (E2) reaches breeding-typical levels (Moore, 1983; Maney et al., 2009). Males respond to song by singing back, and are more likely to do so if their testosterone (T) levels are elevated (Maney et al., 2009). Because the function of song, and behavioral responses to it, vary according to endocrine state, we manipulated plasma E2 in females and T in males in order to look at the effects on neural responses in the reward pathway. Following these manipulations, we exposed the birds to conspecific male song and quantified the expression of Egr-1 throughout the mesolimbic reward pathway. Because E2 treatment was expected to increase the valence of song, we predicted that responses would be greater in the E2-treated females than in untreated, non-breeding females. T-treatment was expected to lower the valence of an already negative stimulus, so we predicted little or no effect of T-treatment on the magnitude of mesolimbic reward responses in males.

Materials and Methods

Animals

All research was conducted in accordance with National Institutes of Health (NIH) principles of animal care, federal, and state laws, and university guidelines. Twenty-three white-throated sparrows of each sex were captured in mist nets during fall migration and housed initially in mixed-sex aviaries at the animal care facility at Emory University. The sex of the animals was confirmed via PCR analysis of a blood sample (Griffiths et al., 1998). Birds were housed under a short day length (10L:14D) for at least 4 months (Maney et al., 2007, 2008). The day length remained the same throughout the study to prevent gonadal recrudescence and elevation of endogenous E2 and T.

Hormonal Manipulation

Before the start of each experiment, birds were moved to individual cages (15″ × 15″ × 17″) inside walk-in sound-attenuating booths (Industrial Acoustics, Bronx, NY, USA). On the day of transfer, each bird received one subcutaneous silastic capsule (ID 1.47 mm, OD 1.96 mm, Dow Corning, Midland, MI, USA) sealed at both ends with A-100-S Type A medical adhesive (Factor 2, Lakeside, AZ, USA). Females received 12 mm capsules that were either empty (n = 11) or filled with 17β-estradiol (n = 12; Steraloids, Newport, RI, USA). Males received 15 mm capsules that were either empty (n = 11) or filled with T (n = 12; Steraloids). These doses elevate E2 and T to breeding-typical levels in this species (Maney et al., 2008, 2009; Sanford et al., 2010) and stimulated the E2-dependent courtship behavior known as copulation solicitation display (CSD) in this sample. After receiving the capsules, birds were housed in single-sex groups of 4–6 per booth for 7–9 days. All booths were identical.

Stimulus Presentation

On the afternoon prior to stimulus presentation, each bird was isolated by placing its cage inside an empty sound-attenuating booth equipped with microphone, speaker, and video camera. The stimulus playback began at 1 h after lights-on the following morning and was delivered via the speaker located inside the booth. The type of stimulus (song or tones, see below) was balanced across treatment groups for both males and females such that six hormone-treated and six blank-treated birds heard song, and six hormone-treated and five blank-treated birds heard tones. The stimuli were presented at a peak level of 70 dB measured at the bird’s cage (Maney et al., 2008). The stimulus presentation was followed by 18 min of silence. Video recordings of all birds were made during the stimulus presentation. For the females, we counted copulation solicitation events, defined as tail lifts, wing quivers, or vocalizations characteristic of CSD (see Maney et al., 2003). For the males, we counted full and partial songs (see Maney et al., 2009).

Sound Stimuli

Songs

White-throated sparrow songs obtained from the Borror Laboratory of Bioacoustics birdsong database were converted to AIFF format and background noise was removed. The recordings were edited so that a song was heard every 15 s, which mimics a natural song rate. Sequences of songs were then spliced together so that the identity of the singer changed to a novel male every 3 min. Presenting a variety of songs helps overcome habituation to the stimulus (Stripling et al., 1997). Each bird within a treatment condition (hormone or blank) heard 14 different singers, in a unique order determined by a balanced Latin square, for a total stimulus duration of 42 min.

Tones

For each of the 14 recordings of males singing, the frequency of each whistle (note) in one song was measured using AudioXplorer (Arizona Software, San Francisco, CA, USA). Songs usually contained five distinct frequencies. For each song, eight sinusoidal tones were generated at these frequencies and arranged in a random order 200 ms apart, resulting in a tone sequence that matched the song in duration, the average number of onsets and offsets, and total sound energy at each frequency. Tone sequences were spliced together as for the song stimuli, with 15 s of silence between each sequence, in an order determined by a balanced Latin Square.

Histology

Sixty min following the onset of the stimulus presentation, birds were deeply anaesthetized with isoflurane (Abbott Laboratories, North Chicago, IL, USA) and decapitated. Ovaries were inspected to confirm a regressed state. Brains were harvested, fixed, and sectioned at 50 μm as previously described (Maney et al., 2003, 2007). Every third 50-μm section was incubated with an antibody against Egr-1 (cat# sc189; Santa Cruz Biotechnology, Santa Cruz, CA, USA), which was subsequently labeled using a biotinylated secondary antibody and avidin-biotin complex (Vector, Burlingame, CA, USA). The specificity of this antibody has been validated in this species via preadsorption studies (Saab et al., 2010). Labeling was visualized using diaminobenzidine enhanced with nickel (Maney et al., 2003, 2007). Sections were mounted onto gelatin-coated slides, dehydrated, and coverslipped in DPX (Sigma, St. Louis, MO, USA).

Quantification of Egr-1 Immunoreactivity

Examples of Egr-1 labeling are shown in Figure 1. We sampled from within the avian homologues of the nAc, caudate nucleus, Hp, medial amygdala, and VTA. We also sampled within an area proposed as an avian homologue of the prefrontal cortex and which receives a strong dopaminergic projection (Mogensen and Divac, 1982; Waldmann and Güntürkün, 1993). The names and abbreviations of each region of interest (ROI) and their human homologues are given in Table 1. Egr-1 immunoreactivity (ir) was quantified in six sections, 150 μm apart, in the VTA and in three sections in each of the other regions. Egr-1-ir was quantified in these regions on one side of the brain, chosen at random except when that region was damaged on one side due to folding or tearing of the section; in these cases the intact side was chosen. Images were acquired with a 4× (nAc and TnA) or 10× objective (all other regions) using a Leica DFC480 camera attached to a Zeiss Axioskop microscope. The light level on the microscope was set exactly the same for each picture.

Sarah E. Earp and Donna L. Maney 

*Department of Psychology, Emory University, Atlanta, GA, USA

 Frontiers

Related birds evolve different songs and colours

Canadian Researchers have discovered a pattern in birds' songs and plumage that help explain some of the colourful and tuneful variety in nature.

The team found that closely related birds that share the same habitat tend to look and sound different.
This evolutionary rule of thumb seems to help birds to identify members of their own species.
Dr Paul Martin presented the findings at the First Joint Congress for Evolutionary Biology in Ottawa.
He and his team studied 250 bird species throughout the world.
With the help of the Macaulay Library of birdsong, they were able to compile a database of where the birds lived and what they looked and sounded like.
"We found, repeatedly, that birds that [live in the same location] with a close relative have more divergent songs and colour patterns," he told BBC Nature.
By Victoria Gill Science reporter, BBC Nature, Ottawa, Canada
more BBC Natures