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Conspecific Song (conspecific + song)
Selected AbstractsThe hippocampus and caudomedial neostriatum show selective responsiveness to conspecific song in the female zebra finchDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2002David J. Bailey Abstract The perception of song is vital to the reproductive success of both male and female songbirds. Several neural structures underlying this perception have been identified by examining expression of immediate early genes (IEGs) following the presentation of conspecific or heterospecific song. In the few avian species investigated, areas outside of the circuit for song production contain neurons that are active following song presentation, specifically the caudal hyperstriatum ventrale (cHV) and caudomedial neostriatum (NCM). While studied in detail in the male zebra finch, IEG responses in these neural substrates involved in song perception have not been quantified in females. Therefore, adult female zebra finches were presented with zebra finch song, nonzebra finch song, randomly generated tones, or silence for 30 min. One hour later they were sacrificed, and their brains removed, sectioned, and immunocytochemically processed for FOS expression. Animals exposed to zebra finch song had a significantly higher density of FOS-immunoreactive cells in the NCM than those presented with other songs, tones, or silence. Neuronal activation in the cHV was equivalent in birds that heard zebra finch and non-zebra finch song, expression that was higher than that observed in the groups that heard no song. Interestingly, the hippocampus (HP) and adjacent parahippocampal area (AHP) were activated in a manner comparable to the NCM. These results suggest a general role for the cHV in song perception and a more specific role for the NCM and HP/AHP in facilitating recognition of and responsiveness to species-specific song in female zebra finches. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 43,51, 2002 [source] Estrogen-dependent selectivity of genomic responses to birdsongEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2006Donna L. Maney Abstract Behavioral responses to sociosexual signals often depend on gonadal steroid hormones, which are thought to modulate behavior by acting on motivational systems in the brain. There is mounting evidence that sex steroids may also modulate perception of sociosexual signals by affecting sensory processing. In seasonally breeding songbirds such as the white-throated sparrow (Zonotrichia albicollis), the female's behavioral response to hearing male song depends on her plasma levels of estradiol (E2). Here, we examined whether plasma E2 also affects the selectivity of the song-induced zenk (egr-1) response in the auditory forebrain, which is known to vary according to the behavioral relevance of song stimuli. Non-breeding females were held on a winter-like photoperiod and implanted with silastic capsules containing either no hormone or E2. E2-treated birds hearing 42 min of conspecific song had more cells immunoreactive for the protein product of zenk in the auditory forebrain than did those hearing frequency-matched synthetic tones. In birds not treated with E2, however, the zenk response to song did not differ from that to tones. We found similar effects in the avian homolog of the inferior colliculus, indicating that E2 may affect the processing of auditory information upstream of the forebrain. Our data suggest that in females, zenk induction in the auditory system is selective for song only when plasma E2 exceeds non-breeding levels. E2-dependent plasticity of auditory pathways and processing centres may promote recognition of and attention to conspecific song during the breeding season. [source] Song similarity predicts hybridization in flycatchersJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2006A. QVARNSTRÖM Abstract Given that population divergence in sexual signals is an important prerequisite for reproductive isolation, a key prediction is that cases of signal convergence should lead to hybridization. However, empirical studies that quantitatively demonstrate links between phenotypic characters of individuals and their likelihood to hybridize are rare. Here we show that song convergence between sympatric pied (Ficedula hypoleuca) and collared flycatchers (F. albicollis) influence social and sexual interactions between the two species. In sympatry, the majority of male pied flycatchers (65%) include various parts of collared flycatcher song in their song repertoire (but not vice versa). Playback experiments on male interactions demonstrate that male collared flycatchers respond similarly to this ,mixed' song as to conspecific song. Long-term data on pairing patterns show that males singing a converged song attract females of the other species: female collared flycatchers only pair with male pied flycatchers if the males sing the mixed song type. From the perspective of a male pied flycatcher, singing a mixed song type is associated with 30% likelihood of hybridization. This result, combined with our estimates of the frequency of mixed singers, accurately predicts the observed occurrence of hybridization among male pied flycatchers in our study populations (20.45% of 484 pairs; predicted 19.5%). Our results support the suggestion that song functions as the most important prezygotic isolation mechanism in many birds. [source] The development of stimulus-specific auditory responses requires song exposure in male but not female zebra finchesDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2010Kristen K. Maul Abstract Juvenile male zebra finches develop their song by imitation. Females do not sing but are attracted to males' songs. With functional magnetic resonance imaging and event-related potentials we tested how early auditory experience shapes responses in the auditory forebrain of the adult bird. Adult male birds kept in isolation over the sensitive period for song learning showed no consistency in auditory responses to conspecific songs, calls, and syllables. Thirty seconds of song playback each day over development, which is sufficient to induce song imitation, was also sufficient to shape stimulus-specific responses. Strikingly, adult females kept in isolation over development showed responses similar to those of males that were exposed to songs. We suggest that early auditory experience with songs may be required to tune perception toward conspecific songs in males, whereas in females song selectivity develops even without prior exposure to song. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2010 [source] | ||||||||||