Specification for red and green filters used in ophthalmic dichromatic and dissociation tests 眼科二色性和分离试验用红绿滤光片规范
2.
On average , wildlife ecologists find that “ dichromatic ” bird species die out nearly 25 percent more often than their monochromatic relatives 野外生态学家发现，平均而言，公、母鸟羽色不同的鸟种，其死亡率比起公、母鸟羽色相同的相似鸟种高了25 % 。
