If Not for Plants, Could Rivers Bend?
Geologists strengthen the case that early rooted plants engineered the look of modern rivers
by Catherine Clabby
For decades, the Canadian geologist Martin Gibling has been intrigued by the tough-to-prove hypothesis that land plants created the shape of modern rivers hundreds of millions of years ago.
Plant roots reinforced the ground, the thinking goes, creating stable banks that funneled what once were wide, shallow water flows into narrower and deeper channels. By extension, that set the stage for lots of significant Earth history events, including the rise of human civilizations in modern river basins so many millennia later.
Now Gibling and postdoctoral scientist Neil Davies, both at Dalhousie University, have strengthened this case. When the pair compared a much-improved plant fossil record with evidence of how rivers changed very long ago, the transitions matched up…
(read more: American Scientist)
photograph: Lee Photography/Alamy