一些科学家推测，火星在早期很长时间里可能都有以河流、湖泊，甚至海洋装点着它的表面。
Some scientists speculate that Mars may have enjoyed an extended early period during which rivers, lakes, and perhaps even oceans adorned its surface.
在克雷默早期的研究中，他发现被关在笼中的候鸟在它们通常开始在迁徙的大致时间会变得非常不安。
Early in his research, Kramer found that caged migratory birds became very restless at about the time they would normally have begun migration in the wild.
即使这种计时方法在细节上是新颖的，早期的农业社会也将时间与自然现象联系在一起。
Even if this method of timekeeping is novel in its particulars, early agricultural societies also connected time to natural phenomena.
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