PBS
When It Was Too Hot for Leaves
Plants first made their way onto land at least 470 million years ago but for their first 80 million years, leaves as we know them today didn’t exist. What held them back?
Professor Dave Explains
Lycophytes: Early Vascular Plants
We learned all about nonvascular plants, which are called bryophytes, so what came next in the evolutionary time line for plants? Eventually vascularization came about, and the first vascular plants were called lycophytes. What were...
Professor Dave Explains
Ferns: The Emergence of Roots and Stems
We just learned about lycophytes, so which plants came next on the evolutionary timeline? Those would be ferns. With ferns we finally arrive at a type of plant which should actually look quite familiar to most people, even though these...