NOVA — S43E08 — Making North America: Human

00:00:01 KIRK JOHNSON: North America, the land that we love

00:03:15 did we turn an unpopulated continent

00:06:02 This is insane

00:08:24 Joe has a replica

00:10:29 to settle along the western edge of the continent

00:12:31 These are really great

00:14:35 but you could do light cutting

00:16:42 Bob Patten has been crafting Clovis point replicas

00:18:35 the spear point penetrates skin, too

00:21:04 In Colorado's Mesa Verde National Park,

00:23:32 at Cahokia, Illinois,

00:25:35 and all agriculture possible

00:27:05 Well, then there's also living matter,

00:28:56 and growers soon hit a wall

00:31:19 By then, prospectors had snatched up

00:33:12 JOHNSON: When Earth was forming, most heavy metals like iron and gold

00:35:21 it's estimated that more than one million pounds of gold

00:37:36 the massive transformation underway was this:

00:40:22 Something like 18 million people live here

00:42:31 Oil is really the DNA of Los Angeles

00:45:07 that rises and falls with Pacific Ocean tides

00:47:33 So the story there, you know, is

00:50:01 Chris estimates that severe earthquakes strike

00:52:32 no landscape is permanent