Darwin had been working on his theory for over twenty years when he published " On the Origin of Species."

VOA: special.2009.12.01

What was neat about it is before that time, the predominant species to use for air conditioning or refrigeration was ammonia.

在这之前是很整洁的，之前最主要的用于空调或者冰箱的,物质是氨。

麻省理工公开课 - 固态化学导论课程节选

For both John of the book of Revelation and for John Milton, it's the superior male of the species that's been singled out for the glorious practice of sexual abstinence.

对约翰的《启示录》和弥尔顿来说，是男人在人类中的优越地位,让禁欲的实行被挑选出来了。

耶鲁公开课 - 弥尔顿课程节选

His team used a method called transient gene silencing to change the genetic structure of the three mosquito species responsible for spreading malaria.

VOA: special.2010.04.20

Notice the importance -and we'll come back to it-- of the word "dominant": "the dominant" in the thinking of the Russian formalists and the struggle for dominance among species in a habitat.

注意这个词的重要性,我们还会讲到，支配，这个词：,俄国形式主义者所说的支配,和物种间争夺栖息地的支配。

耶鲁公开课 - 文学理论导论课程节选

"But they provide habitat for over 25 percent of the marine species."

VOA: standard.2010.05.26

They knew the techniques for grafting and improving, and domesticating species of grapes and olives particularly.

他们知道植物嫁接和改良的工艺,和为葡萄和橄榄培育良种的技术

耶鲁公开课 - 古希腊历史简介课程节选

"For example,when Thomas Henry Huxley first read The Origin of Species, his first thought , 'Well,' he said,of course, 'How extremely stupid not to have thought of that myself.

VOA: standard.2009.11.25