Dry deserts slowly took on a greener hue. Palm tree-like cycads were abundant, as were conifers such as araucaria and pines. Ginkgoes carpeted the mid- to high northern latitudes, and podocarps ...

Today, just a few species of the palm-like plants survive in tropical and subtropical habitats. Like their lumbering grazers, most cycads have gone extinct. Their disappearance from their prior ...