Cuckolds are men whose wives gave birth to infants that were blatantly not t

游客2024-11-21  0

问题     Cuckolds are men whose wives gave birth to infants that were blatantly not their own. The well known trickery of the cuckoo, the bird from which "cuckold" is derived, is as a nest parasite — laying eggs for other birds to hatch and raise. New research suggests the cuckoo has another trick it uses to ruffle its victims’ feathers.
    Common cuckoos usually lay a single egg in the nest of a host bird. The eggs often look remarkably similar to the host’s. Upon hatching, the cuckoo chick eliminates any of its potential rival chicks by pushing them or their eggs out of the nest. However, there is more to this elaborate deceit than is generally realized.
    As far back as ancient times a similarity has been noted between many cuckoo species and hawks, in size, shape and plumage. More recently researchers have discovered that hawk-like markings are more prevalent in cuckoo species that engage in nest parasitism than in cuckoo species that do not. Researchers wondered whether this similarity was noticed by birds too.
    They set up peanut feeding stations and over two years found that great and blue tits, both of which are not parasitised by cuckoos, were the main visitors. They then experimented by placing a mounted specimen of a sparrowhawk, cuckoo, dove, or duck, at the feeders for five minutes. The team reported that the tits were as scared of cuckoos as they were of sparrowhawks, raising alarm calls and staying away from feeders at all costs. With the duck and dove they detected no such behavior.
    When researchers covered the hawk-like markings on the cuckoo the tits treated it as if it were a duck or dove. Covering the same markings on the sparrowhawk had no such effect, but adding them to the dove caused the tits to treat the dove as they would a sparrowhawk or a cuckoo.
    The authors argue that actual cuckoo hosts, such as meadow pipits, dunnocks and reed warblers, may have directed the evolution of the cuckoo’s resemblance to hawks by attacking cuckoos that approached their nests. If a cuckoo with slightly hawk-like plumage caused hosts to delay or avoid an attack in the past, this would have favored the evolution,of hawk mimicry.
    It is an arms race —-and a matter of adapting and counter-adapting. The better the cuckoo disguises its eggs and itself, the more host birds improve their ability to spot the impostor. Although such an evolutionary dynamic may seem like something that exists only in the wild, it is possible for it to happen in human society as well — between cuckolds and their cheating partners, constantly driving men to be better at detecting adultery and women to be better at getting away with it. [br] According to the passage, which of the following statements is correct?

选项 A、Dunnocks and reed warblers attacked cuckoos, so that their nests have escaped the doomed fate of being parasitised.
B、Cockoos have a gift for hawk mimicry. Accordingly, they are not attacked by hosts.
C、Both meadow pipits and reed warblers have contributed to the evolution of hawk mimicry.
D、The hawk-like plumage is favored by actual cuckoo hosts.

答案 C

解析 推断题。从actual cuckoo hosts,such asmeadow pipits,dunnocks and reed warblers可以看出林岩鹨和芦苇莺早已成为布谷鸟的宿主,A错误。从文中可得知并不是所有布谷鸟都有模仿雀鹰羽毛的能力,B错误。从…such as meadow pipits,dunnocksand reed warblers,may have directed theevolution of the cuckoo’s resemblance tohawks…可以看出C正确,草地鹨和芦苇莺都对杜鹃的进化起到一定的促进作用。D与原文不符。
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