Natural selection does not explain everything about why species evolve.

VOA: special.2009.02.25

And in fact, Skinner explicitly made the analogy from the natural selection of species to the natural selection of behavior.

实际上，斯金纳也确实明确地,对物种的自然选择,同行为的自然选择进行过类比。

耶鲁公开课 - 心理学导论课程节选

Some estimates suggest species extinction because of human activity is about 1,000 times faster than the natural rate of loss.

VOA: standard.2010.01.31