19 Cause of the dull Colours of Female Birds

The same law manifests itself in Birds. The female while sitting on her eggs requires protection by concealment¹ to a much greater extent than the male; and we accordingly find that in a large majority of the cases in which the male birds are distinguished² by unusual brilliancy of plumage, the females are much more obscure, and often remarkably³ plain-coloured. The exceptions are such as eminently⁴ to prove the rule, for in most cases we can see a very good reason for them. In particular, there are a few instances among wading⁵ and gallinaceous birds in which the female has decidedly more brilliant colours than the male; but it is a most curious and interesting fact that in most if not all these cases the males sit upon the eggs; so that this exception to the usual rule almost demonstrates that it is because the process of incubation is at once very important and very dangerous, that the protection of obscure colouring is developed. The most striking example is that of the gray phalarope (Phalaropus fulicarius). When in winter plumage, the sexes of this bird are alike in colouration, but in summer the female is much the most conspicuous⁶, having a black head, dark wings, and reddish-brown back, while the male is nearly uniform brown, with dusky spots. Mr. Gould in his “Birds of Great Britain” figures the two sexes in both winter and summer plumage, and remarks on the strange peculiarity⁷ of the usual colours of the two sexes being reversed, and also on the still more curious fact that the “male alone sits on the eggs,” which are deposited on the bare ground. In another British bird, the dotterell, the female is also larger and more brightly-coloured than the male; and it seems to be proved that the males assist in incubation even if they do not perform it entirely⁸, for Mr. Gould tells us, “that they have been shot with the breast bare of feathers, caused by sitting on the eggs.” The small quail-like birds forming the genus Turnix have also generally large and bright-coloured females, and we are told by Mr. Jerdon in his “Birds of India” that “the natives report that during the breeding season the females desert their eggs and associate in flocks while the males are employed in hatching the eggs.” It is also an ascertained⁹ fact, that the females are more bold and pugnacious¹⁰ than the males. A further confirmation¹¹ of this view is to be found in the fact (not hitherto noticed) that in a large majority of the cases in which bright colours exist in both sexes incubation takes place in a dark hole or in a dome-shaped nest. Female kingfishers are often equally brilliant with the male, and they build in holes in banks. Bee-eaters, trogons, motmots, and toucans¹², all build in holes, and in none is there any difference in the sexes, although they are, without exception, showy birds. Parrots build in holes in trees, and in the majority of cases they present no marked sexual difference tending to concealment of the female. Woodpeckers are in the same category, since though the sexes often differ in colour, the female is not generally less conspicuous than the male. Wagtails and titmice build concealed¹³ nests, and the females are nearly as gay as their mates. The female of the pretty Australian bird Pardalotus punctatus, is very conspicuously¹⁴ spotted¹⁵ on the upper surface, and it builds in a hole in the ground. The gay-coloured hang-nests (Icterin?) and the equally brilliant tanagers may be well contrasted; for the former, concealed in their covered nests, present little or no sexual difference of colour — while the open-nested tanagers have the females dull-coloured and sometimes with almost protective tints¹⁶. No doubt there are many individual exceptions to the rule here indicated, because many and various causes have combined to determine both the colouration and the habits of birds. These have no doubt acted and re-acted on each other; and when conditions have changed one of these characters may often have become modified, while the other, though useless, may continue by hereditary¹⁷ descent an apparent exception to what otherwise seems a very general rule. The facts presented by the sexual differences of colour in birds and their mode of nesting, are on the whole in perfect harmony with that law of protective adaptation of colour and form, which appears to have checked to some extent the powerful action of sexual selection, and to have materially influenced the colouring of female birds, as it has undoubtedly¹⁸ done that of female insects.

1 concealment   

n.隐藏, 掩盖，隐瞒

参考例句：

• the concealment of crime 对罪行的隐瞒
• Stay in concealment until the danger has passed. 把自己藏起来，待危险过去后再出来。

2 distinguished   

adj.卓越的，杰出的，著名的

参考例句：

• Elephants are distinguished from other animals by their long noses.大象以其长长的鼻子显示出与其他动物的不同。
• A banquet was given in honor of the distinguished guests.宴会是为了向贵宾们致敬而举行的。

3 remarkably   

ad.不同寻常地，相当地

参考例句：

• I thought she was remarkably restrained in the circumstances. 我认为她在那种情况下非常克制。
• He made a remarkably swift recovery. 他康复得相当快。

4 eminently   

adv.突出地；显著地；不寻常地

参考例句：

• She seems eminently suitable for the job. 她看来非常适合这个工作。
• It was an eminently respectable boarding school. 这是所非常好的寄宿学校。 来自《简明英汉词典》

5 wading   

（从水、泥等）蹚，走过，跋( wade的现在分词 )

参考例句：

• The man tucked up his trousers for wading. 那人卷起裤子，准备涉水。
• The children were wading in the sea. 孩子们在海水中走着。

6 conspicuous   

adj.明眼的，惹人注目的；炫耀的，摆阔气的

参考例句：

• It is conspicuous that smoking is harmful to health.很明显，抽烟对健康有害。
• Its colouring makes it highly conspicuous.它的色彩使它非常惹人注目。

7 peculiarity   

n.独特性，特色；特殊的东西；怪癖

参考例句：

• Each country has its own peculiarity.每个国家都有自己的独特之处。
• The peculiarity of this shop is its day and nigth service.这家商店的特点是昼夜服务。

8 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

9 ascertained   

v.弄清，确定，查明( ascertain的过去式和过去分词 )

参考例句：

• The previously unidentified objects have now been definitely ascertained as being satellites. 原来所说的不明飞行物现在已证实是卫星。 来自《简明英汉词典》
• I ascertained that she was dead. 我断定她已经死了。 来自《简明英汉词典》

10 pugnacious   

adj.好斗的

参考例句：

• He is a pugnacious fighter.他是个好斗的战士。
• When he was a child,he was pugnacious and fought with everyone.他小时候很好斗，跟每个人都打过架。

11 confirmation   

n.证实，确认，批准

参考例句：

• We are waiting for confirmation of the news.我们正在等待证实那个消息。
• We need confirmation in writing before we can send your order out.给你们发送订购的货物之前，我们需要书面确认。

12 toucans   

n.巨嘴鸟，犀鸟( toucan的名词复数 )

参考例句：

• Against it, parakeets and toucans and blue-winged macaws swoop. 晨光下，小鹦鹉、巨嘴鸟和翅膀鲜蓝的金刚鹦鹉展翼翱翔。 来自互联网
• Toucans also have a narrow, feather-like tongue. 巨嘴鸟也有狭窄部份，像羽毛一样的舌。 来自互联网

13 concealed   

a.隐藏的，隐蔽的

参考例句：

• The paintings were concealed beneath a thick layer of plaster. 那些画被隐藏在厚厚的灰泥层下面。
• I think he had a gun concealed about his person. 我认为他当时身上藏有一支枪。

14 conspicuously   

ad.明显地，惹人注目地

参考例句：

• France remained a conspicuously uneasy country. 法国依然是个明显不太平的国家。
• She figured conspicuously in the public debate on the issue. 她在该问题的公开辩论中很引人注目。

15 spotted   

adj.有斑点的，斑纹的，弄污了的

参考例句：

• The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
• Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。

16 tints   

色彩( tint的名词复数 )； 带白的颜色； （淡色）染发剂； 痕迹

参考例句：

• leaves with red and gold autumn tints 金秋时节略呈红黄色的树叶
• The whole countryside glowed with autumn tints. 乡间处处呈现出灿烂的秋色。

17 hereditary   

adj.遗传的，遗传性的，可继承的，世袭的

参考例句：

• The Queen of England is a hereditary ruler.英国女王是世袭的统治者。
• In men,hair loss is hereditary.男性脱发属于遗传。

18 undoubtedly   

adv.确实地，无疑地

参考例句：

• It is undoubtedly she who has said that.这话明明是她说的。
• He is undoubtedly the pride of China.毫无疑问他是中国的骄傲。