The northern mockingbird (Mimus polyglottos, Linnaeus) is considered a classic example of a species in which individuals learn songs throughout adulthood, but this assumption has not been tested rigorously. To assess whether mockingbirds should be categorized as open‐ended learners, I conducted a longitudinal study and a field‐based song‐tutoring experiment. I recorded songs from 15 free‐living, banded, adult males in an earlier year and a later year, and I classified 400 mimetic songs per year per individual, based on the species and vocalization type mimicked. For two of these “mimetic types,” I further classified all the song types of all individuals in their early and later samples. The number of song types increased significantly across years for both mimetic types, and the average number of observed mimetic types per individual was 46.4 and 47.7 in the early and late samples (p = .055). I found no evidence adults learned any tutor stimuli after six months of tutoring, but examples from the scientific literature suggest the tutoring regime might not have been adequate to pass the motivational threshold required for learning. I conclude that mockingbirds probably are open‐ended learners, but that future research is needed to verify experimentally that adults can indeed imitate novel song types.

中文翻译：

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北方知更鸟是经典的开放式歌曲学习者吗？

北部mock（Mimus polyglottos，Linnaeus）被认为是一个典型的例子，其中一个人在整个成年期都会学习歌曲，但是这一假设尚未经过严格的检验。为了评估是否应将mock鸟归类为开放式学习者，我进行了一项纵向研究和一项基于现场的歌曲辅导实验。在较早的一年和较晚的一年，我录制了15位自由生活，有乐队乐队，成年男性的歌曲，根据模仿的物种和发声类型，我每年每人分类400首模拟歌曲。对于其中的两种“模拟类型”，我进一步对早期和晚期样本中所有个人的所有歌曲类型进行了分类。两种模拟类型的歌曲类型数量多年来均显着增加，早期和晚期样本中每个人观察到的模拟类型的平均数量分别为46.4和47.7（p  = .055）。我发现没有证据表明成年人在接受六个月的补习后没有学会任何补习刺激，但是科学文献中的例子表明，补习制度可能不足以超过学习所需的动机门槛。我得出的结论是，模仿鸟可能是开放性学习者，但是需要进行进一步的研究，以通过实验验证成年人确实可以模仿新颖的歌曲类型。