All crop plants have relatives somewhere on the earth, and some gene-flow commonly occurs when two plants are grown close together.

FORBES: Magazine Article

We feel that this exhausts the range of environments that plants have known on Earth during the past 400 million years.

CNN: Plants spread secrets about climate change

The group studied so-called "C3" plants, the most prevalent type of plant life on Earth for the past 400 million years.

CNN: Plants spread secrets about climate change

They are amongst the fastest growing plants on Earth.

CNN: All about algae: Can pond scum power our future?

Dr. JONATHAN OVERPECK (Geosciences, University of Arizona): It's going to come a rate much faster than plants and animals on Earth have ever seen in the time they've been on Earth.

NPR: Warming Will Create Micro-Climates, Scientists Say

The Penn State team carried out the largest genetic study so far of when land plants and fungi first appeared on Earth in an attempt to resolve this debate.

BBC: Earth AP