Because many species need others to survive, the worst possible case for an extinction is a domino-style co-extinctioneffect.
因为很多物种需要其它物种才能延续下去，所以一个物种的灭绝可能导致多米诺效应。
2
But the first study to look into the combined effect of both global warming and deforestation found most species are in danger of extinction.
但是，通过对全球变暖和滥伐森林的共同作用的调查，首次研究便发现许多种类都濒临灭绝危险。
3
On the other hand, humanity's malignant effect on the environment has accelerated the rate of extinction for plants and animals, which now reaches perhaps 50,000 species a year.