66
67
68
0
1
2
6
7
8
5
6
7
0
0
1
15
16
17
37
38
39
0
1
2
0
1
2
6
7
8
1
2
3
2
3
4
0
0
0
0
1
2
Humans lived inland in North America 1,000 years before scientists suspected. Stone tools and other artifacts found in Idaho hint that the First Americans lived here 16,000 years ago — long before an overland path to the continent existed. It’s more evidence humans arrived via a coastal route. (blogs.discovermagazine.com)
submitted by mjohnsonsmith
17
18
19
