'Feather-eating bugs' dull birds “以羽毛为食的病菌”使鸟颜
文章来源:未知 文章作者:meng 发布时间:2009-08-04 05:44 字体: [ ]  进入论坛

Brightly coloured birds can become infected with bacteria that eat their feathers.


Eastern bluebirds can lose their <a href=brilliance1" width="466" border="0" src="/upimg/090804/4_055645_1.jpg" />
Eastern bluebirds can lose their brilliance

That in turn can affect the health of the birds and dull their plumage(鸟类羽毛,翅膀).

The discovery comes from a study that found that 99% of all Eastern bluebirds surveyed in Virginia, US were infected with feather-degrading(不名誉的,可耻的) bacteria.

Such bacteria were first discovered a decade ago, but the latest research is the best evidence yet that the bugs2 affect the colour and health of birds.

"Feather-degrading bacteria are relatively3 new to ornithologists(鸟类学家)," says Alex Gunderson of Duke University in Durham, North Carolina, US.

"The first report of their occurrence on wild birds was published only ten years ago."

Since then, scientists have found that most species of wild bird probably harbour some feather-degrading bacteria in their plumage, sometimes of more than one species.

Feather-degrading bacteria work by hydrolysing the protein beta-keratin, which constitutes over 90% of a feather's mass.

But these bugs are usually found in a minority of birds sampled, and it has not been clear what impact they have on their hosts.

So Gunderson and colleagues Mark Forsyth and John Swaddle of the College of William and Mary in Williamsburg, Virginia, US surveyed a population of Eastern bluebirds (Sialia sialis) living in Virginia.

They found that 99% of all the birds surveyed carried feather-eating bugs, they report in the Journal of Avian Biology.

What's more, they found a correlation4(相互关系,关联) between the bacteria and the brightness of female birds' feathers, with more bacteria causing duller feathers.

Sex difference

"This is some of the best evidence that bacteria are active on the feathers of live birds," says Gunderson.

"The evidence is correlational5, so there is a great deal more work that needs to be done to verify it."

"But it does suggest that feather-degrading bacteria could be an important force influencing the ecology and evolution of birds."

However, the bacteria didn't seem to have a significant impact on the feather colour of male birds, a rare example of a parasite6(寄生虫,食客) appearing to harm one sex while not the other.

"I was surprised that the relationship with feather-degrading bacteria was different for males and females," explains Gunderson.

"It is possible that, because males and females differ somewhat in where they spend their time, they could acquire different species of bacteria that have different effects. It is also possible that physiological7 differences between males and females result in different effects of bacteria."

"This is complete speculation8 and at present we do not know the answer to this question."

Another important result was that the bacterial9 load also correlated with the birds' body condition, which is directly related to the bird's health, and also their reproductive success.

Overall, the results suggest that feather-degrading bacteria may have a significant impact on the birds' ecology.

Birds use feather colours to advertise their health, attract mates and for camouflage10(伪装), so that means the bacteria could also affect the evolution of bird colour.

"If bacteria detrimentally11 influence feather colouration, they may place selective pressure on birds to evolve defences against them," says Gunderson.

"There is evidence that certain avian(鸟类的) traits(特征,品质) are defences against feather-degrading bacteria. For instance, we know that feathers coloured by melanin(黑色素) pigments12(颜料) are resistant13 to bacterial degradation14, and that the preen15(整理羽毛,打扮装饰) oil that birds apply to their plumage inhibits16 the growth of some feather-degrading bacteria."

"In general, an understanding of the influence of feather-degrading bacteria on birds could, to some degree, help explain the evolution of these and other avian traits," he says.


1 brilliance 1svzs     
  • I was totally amazed by the brilliance of her paintings.她的绘画才能令我惊歎不已。
  • The gorgeous costume added to the brilliance of the dance.华丽的服装使舞蹈更加光彩夺目。
2 bugs e3255bae220613022d67e26d2e4fa689     
adj.疯狂的,发疯的n.窃听器( bug的名词复数 );病菌;虫子;[计算机](制作软件程序所产生的意料不到的)错误
  • All programs have bugs and need endless refinement. 所有的程序都有漏洞,都需要不断改进。 来自《简明英汉词典》
  • The sacks of rice were swarming with bugs. 一袋袋的米里长满了虫子。 来自《简明英汉词典》
3 relatively bkqzS3     
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
4 correlation Rogzg     
  • The second group of measurements had a high correlation with the first.第二组测量数据与第一组高度相关。
  • A high correlation exists in America between education and economic position.教育和经济地位在美国有极密切的关系。
5 correlational 3882daf289ddef0e405b2dc87d60ae4b     
  • Systematic research if anything tends to support such correlational data. 系统研究一下,如果有任何倾向支持这种相关性的数据。
  • A descriptive correlational method of investigation was implemented. 样本是高雄地区129位产后六周的产妇接受问卷调查。
6 parasite U4lzN     
  • The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
  • I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫,我要自己养活自己。
7 physiological aAvyK     
  • He bought a physiological book.他买了一本生理学方面的书。
  • Every individual has a physiological requirement for each nutrient.每个人对每种营养成分都有一种生理上的需要。
8 speculation 9vGwe     
  • Her mind is occupied with speculation.她的头脑忙于思考。
  • There is widespread speculation that he is going to resign.人们普遍推测他要辞职。
9 bacterial dy5z8q     
  • Bacterial reproduction is accelerated in weightless space. 在失重的空间,细菌繁殖加快了。
  • Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。
10 camouflage NsnzR     
  • The white fur of the polar bear is a natural camouflage.北极熊身上的白色的浓密软毛是一种天然的伪装。
  • The animal's markings provide effective camouflage.这种动物身上的斑纹是很有效的伪装。
11 detrimentally 42f72b15d2458566b31dc89baefac949     
  • Boyle's Law: When things are going well, someone will inevitably experiment detrimentally. 波义耳定律:如果事情进展不错,那么必有人把实验做坏。 来自互联网
12 pigments 90c719a2ef7a786d9af119297e63a36f     
n.(粉状)颜料( pigment的名词复数 );天然色素
  • The Romans used natural pigments on their fabrics and walls. 古罗马人在织物和墙壁上使用天然颜料。 来自辞典例句
  • The original white lead pigments have oxidized and turned black. 最初的白色铅质颜料氧化后变成了黑色。 来自辞典例句
13 resistant 7Wvxh     
  • Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
  • They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。
14 degradation QxKxL     
  • There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。
  • Gambling is always coupled with degradation.赌博总是与堕落相联系。
15 preen 51Kz7     
  • 50% of men under 35 spend at least 20 minutes preening themselves every morning in the bathroom.50%的35岁以下男性每天早上至少花20分钟在盥洗室精心打扮。
  • Bill preened his beard.比尔精心修剪了他的胡须。
16 inhibits 7fbb1ac5e38d9e83ed670404679a2310     
阻止,抑制( inhibit的第三人称单数 ); 使拘束,使尴尬
  • A small manufacturing sector inhibits growth in the economy. 制造业规模太小有碍经济增长。
  • His bad English inhibits him from speaking freely. 他英语学得不好,这使他不能表达自如。
TAG标签: bird eat bacteria feather