Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido, Japan.
Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
Sci Rep. 2018 Jun 7;8(1):8732. doi: 10.1038/s41598-018-27046-4.
Complex learned behaviors, like bird song and human speech, develop under the influence of both genetic and environmental factors. Accordingly, learned behaviors comprise species specificity and individual variability. Auditory information plays a critical role in vocal learning by songbirds, both to memorize tutor songs and to monitor own vocalizations. Nevertheless, audition-deprived songbirds develop structured, species-specific song patterns. It remains to be elucidated how the auditory input contributes to the development of individual variability of song characteristics. Here we show that an open-ended vocal learner, the canary, annually recapitulates individually unique songs without audition. Although the total number of syllable types was reduced by auditory deprivation, other vocal phenotypes examined in the syllable, phrase, and syntax of songs were conserved between the 1 and 2 years, both in deafened and intact birds. In deafened canaries, approximately 60% of the syllables were yearly reproduced with consistent acoustic features, whereas the remaining syllables were replaced with new ones in an annual cycle of song development. These results indicate that the open-ended vocal learning of canaries involves an audition-independent mechanism for the development of recurrent song idiosyncrasy.
复杂的习得行为，如鸟鸣和人类言语，是在遗传和环境因素的共同影响下发展起来的。因此，习得行为既有物种特异性，也有个体变异性。听觉信息在鸣禽的声音学习中起着至关重要的作用，既能帮助它们记忆导师的歌曲，也能监测自己的叫声。然而，失聪的鸣禽也能发展出具有结构和物种特异性的歌唱模式。目前仍不清楚听觉输入如何促进歌唱特征个体差异的发展。在这里，我们展示了一种开放式的声乐学习者，即金丝雀，在没有听觉的情况下每年都会重复具有独特个体特征的歌曲。尽管听觉剥夺减少了音节类型的总数，但在失聪和正常鸟类中，音节、短语和句法中的其他声音表型在 1 年和 2 年内都保持不变。在失聪的金丝雀中，大约 60%的音节会以一致的声学特征进行每年重复，而其余的音节则会在每年的歌唱发展周期中被新的音节所取代。这些结果表明，金丝雀开放式的声乐学习涉及一种独立于听觉的机制，用于发展周期性的歌唱特质。
