An American Tragedy, How a Mass Extinction Can Help Save Our Forest | Rex Mann | TEDxYoungstown
15:06
Reviving the American forest with the American chestnut | William Powell | TEDxDeExtinction
13:40
The return of the chestnut -- a tree crop archetype | Hill Craddock | TEDxUTChattanooga
18:05
Is the house of history built on foundations of sand? | Graham Hancock | TEDxReading
17:45
How we found out evolution is true: John van Wyhe at TEDxNTU
17:33
Why renewables can’t save the planet | Michael Shellenberger | TEDxDanubia
16:07
Thorium can give humanity clean, pollution free energy | Kirk Sorensen | TEDxColoradoSprings
17:59
What if Everything You Know is Wrong: Bob McDonald at TEDxVictoria 2013
13:59