In research funded by the european union , alessandro bottaro of the university of genoa in italy has devised small keratin bristles that mimic the smallest type of bird feathers , known as coverts .
I think only vivid niltava has such a narrow throat line and it seems normal for female to show contrastingly buffy undertail coverts .
我想只有黄腹琉璃有如此窄的喉线,而且对比鲜明地淡黄色翼下覆羽对母鸟似乎是正常的.
It also showed the more orange underwing coverts " said " to be indicative of red-rumped and what appeared to be a complete ( or nearly so ) nuchal collar .
