近親繁殖讓鳥兒不會唱歌

Just like humans have to learn to talk. Some birds , songbirds aren't born singing . - they have to learn to carry a tune. From So in the beginning , they just bubblebabble. Raissa de Boer, a behavior behavioral ecologist at the Unversity University of Antwerp in Belgium. And they learn from a tweetertutor, so they need an example song in order to learn it.

She says that the example song might come from the chick's father. And over time, the baby bird tweets tweaks that tweet, to make it a songits own. And then it takes almost a year until they are they're fully adults adult, and until the next spring, for the final song to come out.

De Boer and her colleagues investigated that song-learning process in canaries, using two groups of baby birds. : the first consists consisted of inbred birds, whose parents were siblings, ; the second had the parents that were unrelated. And the researchers found that the songs of inbred birds , and those of the other, outbred birds . Sounds sound pretty similar to the human ear. I cannot tell the difference.

But computer analysis revealed that the inbred birds sang notes at slightly different pitches - and with tones that were not quite as pure. So basically the sing they sang out of tune, in comparison to outbred birds. The results appear in the Proceedings of the Royal Society B.

Even though our untrained ears have a hard time telling the tones apart. , female canaries seem seemed to notice. They turned tended to lay smaller eggs, and fewer ovum of them, when they meet mated with inbred birds as opposed with to the better songsters. Suggesting that the quality of the songs' gene a songbird's genes may be revealed in its tunes.

• Words wortsh to be remembered:
  • songbird n. 鸣禽,鸣鸟,女歌手
  • babble n. 潺潺声；胡言乱语 v. 喋喋不休；含糊不清地说，呀呀学语；作潺潺声；泄露
  • Antwerp 安特衛普, 比利時城市
  • tweak n. 拧，捏，扭；苦恼；微调，改进 v. 拧，捏，扭；稍稍调整
  • canary 金丝雀,告密者,歌女 (复数)
  • inbreed vt. 使同系繁殖,使近亲交配,使在内部生成
  • inbred adj. 天生的,生来的,同系繁殖的
  • outbreed vt. 使远系繁殖
  • pitch n. 投；投球；音高；程度；沥青 v. 投掷；为…定音高；搭帐篷；用沥青涂
  • songster n. 歌手,作曲者,诗人,鸣鸟

譯文

就像是人类不得不学会說話谈话, 夜莺们也不是生来就会唱歌滴——它们也不得不去找准旋律。 所以在一开始它们也就是那样呀呀学语。这是Raissa de Boer， 一位比利时安特卫普大学的行为生态学家。而它们需要跟随一位导师，为了学会唱歌它们还需要一首练习曲。

她说,鳥兒們的练习曲也许是来自于它们的老爸。并且随着它们慢慢长大，小鸟会纠正一下自己的鸣叫，找到适合自己的style. 随后，还大约需要一年的时间直到它们完全长大后，直到一年后的春天，最后的练习结果便要出炉。

De Boer 和她的同事们调查了金丝雀的音乐学习之路，她们用的是两组幼鸟：第一组是近亲繁殖的后代，它们的父母是有血缘关系的。第二组的不是近亲的后代。随后研究人员们发现，近亲后代的鸟叫和非近亲后代的鸟叫对人类的耳朵来讲，没什么差别。我就分不清谁是谁呢。

但是，通过电脑分析之后，结果揭示出，近亲的小鸟们有一些不同的音调——并且音色也不是十分纯正。所以它们基本上是唱跑调了，当然是和非近亲的后代相比。 该研究结果已经发表在《皇家协会进展B》杂志上。

而且即使是我们这些没有经过培训的普通听者，都很难分辨出这些音色上的区别，雌性金丝雀貌似是了解的这一点的。当她们和近亲的鸟类交配时，更倾向于产个头小一些并且，数量也少一些的卵，仿佛这样并不利于产生优良歌声的后代。这提示我们，一个夜莺的基因质量也许从它们的音色上就可以看出来一些呢。