Squawking point : a circle of bright yellow skin around a hyacinth macaw 's eye is set off against its blue plumage .
呱呱叫的一点:蓝紫金刚鹦鹉(hyacinthmacaw)眼睛周围一圈明黄色皮肤映衬着蓝色的羽毛。
Feathers don 't last forever . So birds periodically shed their plumage and then sprout replacements .
鸟的羽毛不会永远光洁如新,鸟类必须周期性的进行换羽,长出新的羽毛。
Those species with the most elaborate plumage also have the most diverse and reliable diet : a variety of insects , and fruits rich in complex nutrients .
那些有着最美丽羽毛的鸟儿有各式各样并且稳定的食物:各种昆虫和富含多种营养的水果。
And now a team of paleontologists has published a full-body portrait of another dinosaur , in striking plumage that would have delighted that great painter of birds john james audubon .
" We don 't know why plumage colors are confined to this subset , " stoddard said . " The out of gamut colors may be impossible to make with available mechanisms or they may be disadvantageous . "
During the summer months of june , july and august , the days are longer , giving birders much more time to be out in the field with good lighting to see birds , particularly since many species will be sporting their brilliant summer plumage .
As the photographs above show , the two birds ( cuckoo on the left , sparrowhawk on the right ) are similar in size , shape and plumage , and both have a conspicuous pattern of bars on their breasts-a pattern found on many species of hawk , but not on the cuckoo 's relatives .