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Parental care typically involves elaborate reciprocal within-family interactions, and traits such as parental provisioning and offspring begging should therefore coevolve. There is indeed mounting evidence for a phenotypic covariation, also in the canary (Serinus canaria), our model species. Such covariation may arise due to maternal effects, rendering this relationship particularly sensitive to environmental conditions. Here, we manipulated the social environment by pairing females with either their chosen or non-chosen male. Subsequently, all clutches were cross-fostered to separate pre- and postnatal effects. We found a positive covariation between offspring begging and parental provisioning, which was, however, unaffected by mate preferences, and we found no evidence for differential allocation. In addition, there was no effect of assortative mating, which is thought to reinforce parent–offspring covariation. The fact that parent–offspring covariation is consistently observed in canaries suggests that it is biologically relevant, but it requires further studies to elucidate its sensitivity to environmental variation.

In many species, females show preferences for male vocalizations emitted at low-pitched frequencies. This acoustic parameter seems to be a reliable indicator of male quality. This study aims to evaluate whether modifying the frequency range of male song enhances female canary preferences. To do so, we used the most well-known type of song emitted by male canaries called 'sexy' phrases. These phrases are composed of two-note syllables emitted at a high-speed rhythm with a large frequency bandwidth. Two experiments were carried out, both using copulation solicitation displays as a preference index. In the first experiment, the frequency levels of sexy phrases were modified and female preferences for high, normal or low-pitched frequencies were tested. In the second experiment, only frequency levels of notes that immediately precede and follow the sexy phrases were changed in order to verify if the contrast between the frequency of sexy phrases and of surrounding notes influences female response. Moreover, to evaluate female predispositions and the influence of learning on these predispositions, we tested and compared females reared in acoustic isolation and females reared with singing males. Our study reveals that both groups of females prefer sexy phrases emitted at normal and low frequencies. These results let us suppose that learning helps to maintain present predispositions. The second experiment shows that there is no influence of the frequency contrast between sexy phrases and surrounding notes on these preferences in either group.

The aim of this study is to examine the preferences of female canaries for a particular cue in male song: the intra-syllabic diversity (number and form of notes constituting a syllable) and to test both the role of predispositions and of song experience in the development of these preferences. Two groups of females were used. The first consisted of adult females raised in acoustic isolation without song males experiences (ISO group); the second, of song experienced adult females raised with singing male in an aviary (AVI group). Female preferences for intra-syllabic diversity were evaluated using the behavioral index of copulation solicitation displays (CSD). Five different types of songs were tested: three were made up of poor intra-syllabic diversity and two were made up of great intra-syllabic diversity. The results demonstrate that, in each group (AVI and ISO), intra-syllabic diversity is preferred to intrasyllabic simplicity. In addition, the inter-group comparison showed no significant differences between the two groups. In the aviary group, song learning by sexual and sound experience did not seem to modify or influence the intra-syllabic diversity preferences. Thus, female preferences for such a diversity would result from early predispositions that are maintained in adulthood.

In the domesticated common canary (Serinus canaria) a particular phrase called phrase A elicits a high level of sexual responses in females. We know that during male/female or male/male encounters, emitters produce longer phrases A. The aim of this study was to test song influences on adult male canaries and especially the influence of phrases A. We used two sets of conspecific songs (the first set containing phrase A, the second set lacking phrase A), and one set of heterospecific songs (control set). Responses of eighteen males were measured using calls rate. We observed that numbers of calls emitted during silence are similar, regardless to the songs we played back. Conversely, we observed that calls rate is significantly lower during playbacks of phrases A than during the two other types of song playbacks. This suggests that males may discriminate among songs, especially between phrases A and other types of conspecific phrases.

Abstract Laboratory experiments were designed to examine the influence of previous acoustic experience on later song preferences in female domesticated canaries (Serinus canaria). Young females were reared in acoustic isolation (five groups). In these five groups, one was reared without tutoring and four were exposed to taped tutoring songs (playbacks of three different songs, two conspecific and one heterospecific). One of the four tutored groups was exposed to all three songs, while each of the remaining groups was exposed to one of the three songs. When adult, all females were tested using copulation solicitation displays as an index of their song preferences. We demonstrated that females reared without tutoring were especially responsive to a particular domesticated canary song. This song contained a special song phrase type (Vallet & Kreutzer, 1995) that elicits high levels of sexual response. In general, a similar preference was also observed in the groups reared with tutoring. In addition, the females' preferences in tutored groups were also positively and strongly affected by conspecific songs, when these songs had been heard during the previous tutoring. In fact, females seemed to be able to selectively respond to a song containing a special song phrase, but were also able to learn conspecific songs.

The song of male canaries (Serinus canaria) differs greatly from one strain to another (wild and different domesticated breeds) depending on breeders' attempt during selective breedings. Female canaries (common canary strain) previously treated with estradiol were tested for their sexual copulation solicitation display in response to heterospecific and conspecific song stimuli. Heterospecific songs, winter wren (Troglodytes troglodytes) and greenfinch (Chloris chloris), elicited significantly weak reactions from females, but most of the females did react to these heterospecific songs. Two conspecific songs, the females' own strain song and a Border song, elicited significantly strong reactions compared to Harzer roller. A wild canary song has an intermediate song potential between Border and Harzer roller. As a whole these results support the ideas that artificial selection may have relaxed the strength of reproductive isolation and sexual selection.

This study on the organization and detailed acoustic morphology of birdsong deals with the implication of domestication upon behaviour. The songs of wild canaries (Serinus canaria) and different domesticated strains of canary were studied. These included border canaries, bred for appearance in Britain and song canaries, selected for song quality in Germany. The basic rules for developing song architecture, involving rules for assembling individually learned utterances into songs emerge by self-differentiation without any auditory or feedback stimuli. By contrast, the fine structure of notes is shaped by individual learning. A comparison of songs of wild canaries and of different domesticated breeds reveals how selective breeding can alter the behavioural programmes and the general acoustic morphology of learned notes. The results of this comparison can be summarized as follows: 1. All canaries sing phrases according to an identical programme. The temporal patterning of single utterances is very similar. 2. Quantitative differences are found in the proportion of single notes and trilled sequences or tours: Single note complexes are dominant in wild canary song, whereas in the domesticated breeds tours form the bulk of the songs. This quantitative difference is responsible for a highly contrasting impression to our ears of songs that are highly variable in the wild form, and very stereotyped in domesticated song canaries. Canary breeders select strongly for longer repetitions of identical utterances (duration of tours). Border canaries, which are not selected for this trait sing short tours, far more similar to the wild conspecifics than to the song canaries. 3. Low-pitched songs are highly esteemed by bird fanciers. The maximum frequency used by song canaries is much lower than that used by wild birds. 4. One can distinguish by ear approximately ten main syllable-categories, which recur in nearly every individual repertoire. This categorization is based on differences in their acoustic properties. To assess the subjective impression that individual learning is highly channeled in a few predictable overall categories, a reproducible method to define these universal categories has been developed: Individual repertoires depicted on sonagrams were analysed by using a dichotomous key of specific song characteristics and divided into 31 classes: The frequency of use of the syllable categories by individuals with totally different song repertoires was surprisingly similar: Some classes are highly overrepresented, whereas others are underrepresented. Thus wild and domesticated canaries form their individual repertoires according a similar array of characteristics. Thus species-specificity in the general acoustic morphology is based on rules for linking variable components of notes. Individuality is an attribute of single components, such as the pattern of frequency modulation and sequential patterning. One can demonstrate that the general acoustic morphology has remained astonishingly stable during the long process of domestication. The learning process seems to be restricted to a limited set of combinations of note components. Only a few characteristics of syllables appear to have been changed by domestication: e.g. rough syllables have nearly been eliminated, whereas very short syllables (below 50 ms) have become far more frequent.