因噪音污染严重 鸟儿求偶需加大分贝

Change of tune: Research has revealed male great tits are having to sing at higher frequencies to make themselves heard, but unfortunately for them this makes them less attractive to the opposite sex It's not just humans that struggle to make themselves heard with the opposite sex in a city. Research has revealed male birds are also having to change their tune in a bid to find a mate. Scientists have found that male great tits are being forced to sing at higher frequencies to drown out the constant urban din of modern life.

电视上五花八门的相亲节目在刺激着城市中诸多剩男剩女的神经末梢，也许我们并没有意识到除了我们自己，和我们一同生活在一个领域的动物也需要“相亲”。随着城市化的道路愈发明显，城市独有的污染也伴随而来，比如光污染、水污染以及声污染等等，这些城市弊病不仅危害着我们的健康，就连和我们一同生活在一个领域的动物，比如鸟儿也受到不良影响。据悉，研究者发现，生活在城市中的雄性鸟类在对雌性鸟类发出“求偶信号”时，必须发出声频“更高、更尖”的叫声、或者改变声调为了让自己爱的雌性鸟儿听到。有意思的是，这一现象与如今城市中的“剩男”增多现象有异曲同工之妙。

But this is seen by the females as less attractive, and so those that sing at this pitch as well as those that cannot make their low-frequency songs heard are at risk of not finding a special feathered 'friend'. Wouter Halfwerk, of Leiden University in the Netherlands, carried out the research. His team recorded the communication between male and female great tits in a Dutch national park between April and May 2009 and 2010. They analysed the paternity of chicks and played the female birds recordings of male songs with different levels of background noise.

尽管城市里的雄性鸟儿用“如此高昂”的声调来向自己心爱的异性求爱，然而我们的异性鸟儿却对这样的求爱方式不是十分感冒。来自荷兰的研究专家Wouter Halfwerk记录了在荷兰国家公园2009年和2010年4月到5月间，雄鸟和雌鸟之间的互动情况，他们将不同噪音情况下的雄性鸟儿的声音录下来，观看雌性鸟儿的反映。

And they found that the birds that sang low-frequency songs were less likely to be cuckolded. He told the Telegraph: 'These data are critical for our understanding of the impact of anthropogenic noise on wild-ranging birds. 'This is because they provide evidence for low-frequency songs being linked to reproductive success and to be affected by noise-dependent signal efficiency.'

他们发现，那些唱着低频声调歌曲的鸟儿成功求偶机率相当低，专家说：“这些数据对我们了解城市中噪音对动物影响情况十分十分重要，给我们鸟类生殖、繁衍所需要的环境情况提供了许多依据和重要数据。”