By Victoria Gill, BBC News

媒体英语会带大家一起学习BBC撰稿人在报道世界大事时常用到的单词和短语。

Background: 芬兰科学家最近指出，气候变化影响该国不同颜色猫头鹰群体的比例。芬兰赫尔辛基大学研究人员报告说，在温暖气候里，棕色猫头鹰比灰色猫头鹰更容易存活。

Despite their name, tawny owls actually come in two colours. And in Finland, the freezing, snowy winters give pale grey birds a camouflage advantage over their darker brown-feathered counterparts. But as the Finnish winters get milder, the grey owls are disappearing.

The University of Helsinki team gathered 30 years' worth of genetic and population data on tawny owls. They found that the birds inherited their plumage colour from their parents. The grey tawnys, as well being better hidden from predators in the snow, seem to be endowed with other genetic advantages that make them healthier and stronger. But despite this, the brown owl population is now overtaking that of the greys, because the warmer winters have improved the brown owls' chances of survival.

The lead researcher, Dr Patrik Karell, said that this showed that the birds were evolving in response to climate change, so the tawny owl gene pool is actually getting browner. This is the first evidence of climate change having such an effect in the animal kingdom.