家雀一直以来都在被人类深入研究，基因测试表明，它们的幼崽约有四分之一来自配偶以外的其它雄性。

Among barn swallows, that have been extensively studied, about a quarter of the nestlings were sired by a male other than the mate, according to genetic tests.

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几年前，当传闻英国爱鸟者们忧心忡忡于家雀的灭绝而指定了一名“麻雀沙皇”时，似乎“沙皇热”已经达到了顶峰。

WHEN, a few years ago, word came that British bird lovers anxious about the decline of the house sparrow had appointed a sparrow tsar, it seemed that the tsar vogue must have reached its zenith.

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