It was a period of warm humid climate with large areas lf temperate and subtropical forest, but only limited grasslands, as the grasses were of very recent origin.

• 当时气候温暖潮湿，除了有限的草地之外，拥有大面积的温带及亚热带雨林，这是因为大量草本植物是在近代才进化产生的。