1
00:00:06,040 --> 00:00:07,873
NARRATOR: Deep inside
the labyrinth
2
00:00:07,875 --> 00:00:11,043
of a flooded cave system...
3
00:00:11,045 --> 00:00:13,812
MAN: All of a sudden,
the floor just drops.
4
00:00:13,814 --> 00:00:17,016
NARRATOR: Divers come across
human remains.
5
00:00:17,018 --> 00:00:18,717
MAN: You can see
these dark eye sockets
6
00:00:18,719 --> 00:00:20,319
kind of looking back at us.
7
00:00:20,321 --> 00:00:23,922
NARRATOR: And the bones of
giant prehistoric creatures.
8
00:00:23,924 --> 00:00:29,411
MAN: Saber-tooth cats, bears,
giant ground sloths.
9
00:00:29,413 --> 00:00:31,563
NARRATOR: Discoveries that
could revolutionize
10
00:00:31,565 --> 00:00:33,165
our understanding
11
00:00:33,167 --> 00:00:36,969
of how the first humans
came to the Americas.
12
00:00:36,971 --> 00:00:39,571
MAN: They must have
come here another way.
13
00:00:39,573 --> 00:00:42,007
¶ ¶
14
00:00:42,009 --> 00:00:48,480
¶ ¶
15
00:00:48,482 --> 00:00:54,887
¶ ¶
16
00:00:54,889 --> 00:00:57,956
ALBERTO NAVA: We have 800 miles
of underwater tunnels
17
00:00:57,958 --> 00:01:01,260
that have been mapped.
18
00:01:01,262 --> 00:01:04,997
We think there's another half
still to be discovered.
19
00:01:04,999 --> 00:01:08,434
¶ ¶
20
00:01:08,436 --> 00:01:14,540
¶ ¶
21
00:01:14,542 --> 00:01:16,809
NARRATOR: A team of divers
is exploring
22
00:01:16,811 --> 00:01:21,647
the world's largest underground
flooded cave system.
23
00:01:21,649 --> 00:01:24,016
ALBERTO: It's like a labyrinth
of tunnels everywhere,
24
00:01:24,018 --> 00:01:30,355
almost like a Swiss cheese
in the ground, full with water.
25
00:01:30,357 --> 00:01:33,325
NARRATOR: Their aim:
to survey this lost world,
26
00:01:33,327 --> 00:01:37,329
sealed off from humanity
since the Ice Age.
27
00:01:37,331 --> 00:01:41,767
¶ ¶
28
00:01:41,769 --> 00:01:47,940
¶ ¶
29
00:01:47,942 --> 00:01:49,641
ALBERTO: The Yucatán is special,
30
00:01:49,643 --> 00:01:52,644
because all the cave here
were once dry.
31
00:01:52,646 --> 00:01:56,415
We know this because of the
stalagmites and the stalactites
32
00:01:56,417 --> 00:02:00,085
which only form in a dry cave.
33
00:02:00,087 --> 00:02:04,123
About 12,000 years ago,
at the end of the Ice Age,
34
00:02:04,125 --> 00:02:08,393
the ice sheet melted
and the cave began to flood.
35
00:02:08,395 --> 00:02:10,562
NARRATOR: Now,
these flooded caves
36
00:02:10,564 --> 00:02:13,999
pose grave risks to the divers.
37
00:02:14,001 --> 00:02:16,368
ALBERTO: Caves can be
very dangerous.
38
00:02:16,370 --> 00:02:18,370
You have, you know,
going in an environment
39
00:02:18,372 --> 00:02:23,609
where, if you have a problem,
you cannot ascend.
40
00:02:23,611 --> 00:02:27,546
The tunnel that you're traveling
is totally dark.
41
00:02:30,284 --> 00:02:33,318
Your lights now
not have a way to see.
42
00:02:33,320 --> 00:02:34,686
If you go in a small area,
43
00:02:34,688 --> 00:02:40,325
you could get trapped inside the
cave, so there's a lot of risk.
44
00:02:40,327 --> 00:02:44,663
NARRATOR: The team's goal is
to map this complex network.
45
00:02:46,617 --> 00:02:48,300
ALBERTO: When we go
into these tunnels,
46
00:02:48,302 --> 00:02:52,137
we do a very simple map
of the cave.
47
00:02:52,139 --> 00:02:53,272
Then we bring the camera,
48
00:02:53,274 --> 00:02:58,010
and then what we do is
we take a lot of images.
49
00:02:58,012 --> 00:03:03,649
NARRATOR: It's taken 150 hours
to map as far as this point,
50
00:03:03,651 --> 00:03:07,686
and now the divers stop.
51
00:03:07,688 --> 00:03:11,523
ALBERTO: All of a sudden
the floor just drops.
52
00:03:11,525 --> 00:03:14,259
We have these really powerful
underwater lights,
53
00:03:14,261 --> 00:03:18,030
and all you can see
was darkness.
54
00:03:18,032 --> 00:03:22,901
So, like, the biggest, darkest
hole we've seen on the cave.
55
00:03:25,472 --> 00:03:28,974
NARRATOR: Using the divers' own
data and imagery,
56
00:03:28,976 --> 00:03:32,361
the scale of the abyss
becomes clear.
57
00:03:32,363 --> 00:03:34,813
¶ ¶
58
00:03:34,815 --> 00:03:40,586
¶ ¶
59
00:03:40,588 --> 00:03:41,987
ALBERTO: If we were
to drain the water,
60
00:03:41,989 --> 00:03:47,092
we would see this
bell-shaped structure,
61
00:03:47,094 --> 00:03:51,964
maybe like a football field,
stadium kind of size.
62
00:03:51,966 --> 00:03:58,337
¶ ¶
63
00:03:58,339 --> 00:04:02,874
NARRATOR: They name the vast
cave Hoyo Negro;
64
00:04:02,876 --> 00:04:04,876
Black Hole.
65
00:04:07,815 --> 00:04:10,349
ALBERTO: As we descended
into the pit,
66
00:04:10,351 --> 00:04:11,583
we were moving our lights,
67
00:04:11,585 --> 00:04:14,152
trying to figure out
what was down there.
68
00:04:14,154 --> 00:04:16,572
¶ ¶
69
00:04:16,574 --> 00:04:21,727
¶ ¶
70
00:04:21,729 --> 00:04:24,396
NARRATOR: Anything Alberto
and his team find here
71
00:04:24,398 --> 00:04:30,168
will come from prehistory,
when the abyss was a dry cave.
72
00:04:30,170 --> 00:04:35,340
¶ ¶
73
00:04:35,342 --> 00:04:39,778
ALBERTO: And then,
then we saw a bone.
74
00:04:39,780 --> 00:04:43,582
It was a really long, tall bone.
75
00:04:43,584 --> 00:04:46,852
We moved around it,
and then we saw another bone.
76
00:04:50,257 --> 00:04:52,024
We started noticing
that there were,
77
00:04:52,026 --> 00:04:55,560
there were remains
all over the place on the floor.
78
00:04:58,399 --> 00:05:02,567
Whatever they were, it has to
have been a really big animal.
79
00:05:05,739 --> 00:05:08,640
We knew we found something
really important here,
80
00:05:08,642 --> 00:05:11,510
so we mapped everything
in the cave,
81
00:05:11,512 --> 00:05:15,947
recorded the exact locations
of the bones and took photos,
82
00:05:15,949 --> 00:05:20,152
and then we sent all our data
to our colleagues in California.
83
00:05:22,690 --> 00:05:27,225
¶ ¶
84
00:05:27,227 --> 00:05:29,795
DOMINIQUE RISSOLO: Our goal
is to capture these places,
85
00:05:29,797 --> 00:05:34,733
these wild places, using
our visualization systems.
86
00:05:34,735 --> 00:05:38,870
¶ ¶
87
00:05:38,872 --> 00:05:40,739
VID PETROVIC: Okay,
I'm just gonna go through
88
00:05:40,741 --> 00:05:42,274
the different views.
89
00:05:42,276 --> 00:05:44,710
¶ ¶
90
00:05:44,712 --> 00:05:49,748
¶ ¶
91
00:05:49,750 --> 00:05:54,186
So, we're now just kind of
reliving the dive paths.
92
00:05:54,188 --> 00:05:57,856
NARRATOR: In 2014,
Dominique Rissolo and his team
93
00:05:57,858 --> 00:06:02,260
begin to process the divers'
mapping data and images.
94
00:06:02,262 --> 00:06:07,933
Their aim is to create a 3D
digital replica of Hoyo Negro,
95
00:06:07,935 --> 00:06:10,869
which they can explore
from dry land.
96
00:06:10,871 --> 00:06:13,405
DOMINIQUE: The divers have
tremendous experience
97
00:06:13,407 --> 00:06:17,676
in doing different kinds of
documentation underwater,
98
00:06:17,678 --> 00:06:21,446
and we're able to take
all of those images,
99
00:06:21,448 --> 00:06:24,149
and through
computer vision algorithms,
100
00:06:24,151 --> 00:06:26,852
translate them into a 3D model.
101
00:06:26,854 --> 00:06:31,189
And it's really, essentially, a
point cloud, a cloud of points.
102
00:06:33,961 --> 00:06:38,130
VID: So far we have around
15 billion reconstructed points.
103
00:06:39,767 --> 00:06:42,267
The exciting thing is
it grows every year,
104
00:06:42,269 --> 00:06:44,786
so every time they go diving,
take pictures,
105
00:06:44,788 --> 00:06:46,238
we run new reconstructions.
106
00:06:46,240 --> 00:06:49,674
We just add to the set.
107
00:06:49,676 --> 00:06:51,076
DOMINIQUE: The way
that we can create
108
00:06:51,078 --> 00:06:54,579
maybe a more photo-realistic
3D model
109
00:06:54,581 --> 00:06:57,766
is by then texturing
those points
110
00:06:57,768 --> 00:06:59,317
with the original photographs.
111
00:06:59,319 --> 00:07:01,286
So, these are
high-resolution images
112
00:07:01,288 --> 00:07:06,958
that can be essentially draped
on to this 3D point cloud.
113
00:07:06,960 --> 00:07:11,396
¶ ¶
114
00:07:11,398 --> 00:07:17,803
¶ ¶
115
00:07:17,805 --> 00:07:21,706
DOMINIQUE: Wow, so, here we are
at the bottom of Hoyo Negro.
116
00:07:21,708 --> 00:07:23,275
JOEL POLIZZI: This is one
of the most powerful
117
00:07:23,277 --> 00:07:26,411
virtual reality systems
in the world.
118
00:07:26,413 --> 00:07:30,081
¶ ¶
119
00:07:30,083 --> 00:07:32,317
Being inside the SunCAVE
is similar
120
00:07:32,319 --> 00:07:33,785
to being on the dive itself,
121
00:07:33,787 --> 00:07:36,154
with the exception that
you're able to be well lit.
122
00:07:36,156 --> 00:07:40,058
You're able to see everything
that you can't see.
123
00:07:40,060 --> 00:07:43,895
DOMINIQUE: This is essentially
an interactive digital twin
124
00:07:43,897 --> 00:07:48,200
that enables us to come here
and do virtual dives,
125
00:07:48,202 --> 00:07:50,569
and sometimes even
find new animals.
126
00:07:50,571 --> 00:07:53,338
Finding new animals
in a virtual cave, right?
127
00:07:53,340 --> 00:07:57,876
So, exploring a real cave
by using a virtual one.
128
00:07:57,878 --> 00:08:03,548
¶ ¶
129
00:08:03,550 --> 00:08:07,018
The first big animal
that the divers came upon
130
00:08:07,020 --> 00:08:09,921
was right here,
this gomphothere.
131
00:08:12,392 --> 00:08:15,126
It wasn't as if it was
just this proboscidean,
132
00:08:15,128 --> 00:08:18,163
this relative of the elephant.
133
00:08:18,165 --> 00:08:24,035
It's such an incredible
diversity of Ice Age fauna.
134
00:08:24,037 --> 00:08:26,605
Bears,
135
00:08:26,607 --> 00:08:30,775
saber-tooth cats,
136
00:08:30,777 --> 00:08:33,712
giant ground sloths.
137
00:08:35,883 --> 00:08:38,283
Just amazing!
138
00:08:38,285 --> 00:08:42,220
So, Joel, if you take us sort of
onto the wall of the cave here,
139
00:08:42,222 --> 00:08:48,627
we can see this saber-tooth cat
emerge, Smilodon fatalis.
140
00:08:48,629 --> 00:08:51,696
Clinging to the wall we see,
you know, another scapula,
141
00:08:51,698 --> 00:08:56,601
of course, the scapula over here
of the giant ground sloth.
142
00:08:56,603 --> 00:08:58,904
Its ribs.
143
00:08:58,906 --> 00:09:00,772
NARRATOR:
By examining the bones,
144
00:09:00,774 --> 00:09:06,545
Dominique's colleagues identify
at least 16 Ice Age species.
145
00:09:08,882 --> 00:09:10,348
DOMINIQUE: Whether they were
looking for water,
146
00:09:10,350 --> 00:09:13,685
or to build a den,
or even to hunt,
147
00:09:13,687 --> 00:09:15,253
these are massive animals
148
00:09:15,255 --> 00:09:17,389
that were walking through
these passageways,
149
00:09:17,391 --> 00:09:20,091
coming to the edge
of this precipice
150
00:09:20,093 --> 00:09:23,728
and making their way
to the bottom of this pit.
151
00:09:23,730 --> 00:09:28,500
It's a really wonderful view
into what the planet was like
152
00:09:28,502 --> 00:09:31,102
at a time
thousands of years ago.
153
00:09:34,041 --> 00:09:36,908
As incredible as those
discoveries were,
154
00:09:36,910 --> 00:09:39,911
that wasn't the only thing
they found that day.
155
00:09:52,559 --> 00:09:55,927
ALBERTO: We were swimming
at the bottom of the site,
156
00:09:55,929 --> 00:09:58,296
looking at the animal remains,
157
00:09:58,298 --> 00:10:00,131
and then all of a sudden
my friend, Alex,
158
00:10:00,133 --> 00:10:02,133
just moved his light
159
00:10:02,135 --> 00:10:04,936
and he pointed in
a particular direction.
160
00:10:06,907 --> 00:10:08,673
NARRATOR:
Within touching distance,
161
00:10:08,675 --> 00:10:11,977
at the bottom of the vast,
flooded cave system,
162
00:10:11,979 --> 00:10:14,546
diver Alberto Nava and his team
163
00:10:14,548 --> 00:10:19,451
are about to make the discovery
of a lifetime.
164
00:10:19,453 --> 00:10:22,854
ALBERTO: We see this
beautiful cranium.
165
00:10:24,558 --> 00:10:28,493
It's just sitting,
sitting upside down.
166
00:10:28,495 --> 00:10:30,495
You can see these
dark eye sockets
167
00:10:30,497 --> 00:10:32,731
kind of looking back at us.
168
00:10:35,469 --> 00:10:37,235
DOMINIQUE: My blood ran cold.
169
00:10:37,237 --> 00:10:41,239
I mean, my hairs stood on end.
170
00:10:43,577 --> 00:10:45,910
ALBERTO: I don't think I'll find
anything like that
171
00:10:45,912 --> 00:10:47,846
in my exploration life.
172
00:10:47,848 --> 00:10:51,883
This is probably the best
it's ever gonna get.
173
00:10:51,885 --> 00:10:53,351
DOMINIQUE: All these things
come to mind.
174
00:10:53,353 --> 00:10:54,753
Who was this person?
175
00:10:54,755 --> 00:10:58,289
You know, how did they
come to be here?
176
00:10:58,291 --> 00:11:01,660
When did they arrive
at the bottom of this pit?
177
00:11:10,337 --> 00:11:12,003
NARRATOR:
To help find the answers,
178
00:11:12,005 --> 00:11:15,273
the team consults experts
from around the world,
179
00:11:15,275 --> 00:11:16,474
led by Mexico's
180
00:11:16,476 --> 00:11:20,779
National Institute of
Anthropology and History.
181
00:11:20,781 --> 00:11:22,814
DOMINIQUE: We have now
over 30 scientists
182
00:11:22,816 --> 00:11:25,684
and engineers involved:
183
00:11:25,686 --> 00:11:27,218
the paleontologists,
184
00:11:27,220 --> 00:11:29,921
the archaeologists
and anthropologists
185
00:11:29,923 --> 00:11:35,160
who are all helping to put
together this puzzle.
186
00:11:35,162 --> 00:11:36,628
JIM CHATTERS:
We have a fairly consistent
187
00:11:36,630 --> 00:11:40,165
3,000-year offset between...
188
00:11:40,167 --> 00:11:41,299
DOMINIQUE: As a project,
we made the decision
189
00:11:41,301 --> 00:11:42,801
to reach out to Jim Chatters,
190
00:11:42,803 --> 00:11:47,672
who had the experience and
expertise we really needed
191
00:11:47,674 --> 00:11:52,110
to understand the significance
of the site of Hoyo Negro
192
00:11:52,112 --> 00:11:54,446
and everything it contained.
193
00:11:56,750 --> 00:11:59,584
JIM: Well, you just don't see
this, this kind of preservation,
194
00:11:59,586 --> 00:12:03,488
so it's just
unbelievable quality.
195
00:12:03,490 --> 00:12:08,293
¶ ¶
196
00:12:08,295 --> 00:12:10,862
NARRATOR: The first question
on the team's mind,
197
00:12:10,864 --> 00:12:15,266
"Who is this person at
the bottom of the cave?"
198
00:12:15,268 --> 00:12:18,837
¶ ¶
199
00:12:18,839 --> 00:12:22,073
DOMINIQUE: I shared photographs
of the discoveries,
200
00:12:22,075 --> 00:12:24,876
and his eyes lit up.
201
00:12:24,878 --> 00:12:27,612
I could see his hands
trembling a little bit.
202
00:12:27,614 --> 00:12:30,482
JIM: And here's our human.
203
00:12:32,586 --> 00:12:39,357
The skeleton is, it's a diary
of someone's life.
204
00:12:39,359 --> 00:12:42,327
And it's especially a diary
of their early years.
205
00:12:44,631 --> 00:12:49,067
This is a really good
picture here.
206
00:12:49,069 --> 00:12:51,770
Here's the telling piece.
207
00:12:51,772 --> 00:12:52,704
I can see, first of all,
208
00:12:52,706 --> 00:12:54,239
that a feature
in the base of the skull
209
00:12:54,241 --> 00:12:57,408
called the "basilar suture"
was still open,
210
00:12:57,410 --> 00:13:03,148
and that tends to close
somewhere around the twenties.
211
00:13:03,150 --> 00:13:05,083
And it was not only
a full-size skull,
212
00:13:05,085 --> 00:13:10,321
but the third molars
had already erupted.
213
00:13:10,323 --> 00:13:13,391
So, it's a fully formed tooth,
or nearly fully formed,
214
00:13:13,393 --> 00:13:17,195
which puts this
more than 15 years old.
215
00:13:17,197 --> 00:13:21,199
In looking at this, right away
I'm thinking 16 to 19 years
216
00:13:21,201 --> 00:13:24,235
is the most likely age
of this individual.
217
00:13:27,541 --> 00:13:28,606
To determine the sex of a skull,
218
00:13:28,608 --> 00:13:32,811
you're looking at how
rugged it is, mainly.
219
00:13:32,813 --> 00:13:36,114
In this case, what I did was
I look at the mastoid processes,
220
00:13:36,116 --> 00:13:39,284
and that's the position
on the skull here
221
00:13:39,286 --> 00:13:41,953
where the large neck muscles
attach,
222
00:13:41,955 --> 00:13:45,123
and they tend to be large
in males and small in females.
223
00:13:45,125 --> 00:13:49,060
And in this case,
they were very small.
224
00:13:49,062 --> 00:13:53,264
I asked Dominique if anyone had
told him what he had there,
225
00:13:53,266 --> 00:13:55,733
and he said, "No, they hadn't."
226
00:13:55,735 --> 00:13:56,968
And I said, "Well,
what you've got here
227
00:13:56,970 --> 00:14:00,605
is the bones of a teenage girl,
228
00:14:00,607 --> 00:14:04,175
and a bunch of
really large megafauna."
229
00:14:05,846 --> 00:14:08,847
This is the first time
we have a human skull
230
00:14:08,849 --> 00:14:12,750
in direct association with the
skeleton of an extinct animal
231
00:14:12,752 --> 00:14:15,386
in the Americas, period.
232
00:14:15,388 --> 00:14:17,655
That's really exciting.
233
00:14:19,392 --> 00:14:21,292
NARRATOR:
Over successive dives,
234
00:14:21,294 --> 00:14:23,962
the team finds and scans
more bones
235
00:14:23,964 --> 00:14:26,731
belonging to the teenage girl.
236
00:14:26,733 --> 00:14:31,035
By 2013, they've documented
her near-complete skeleton,
237
00:14:31,037 --> 00:14:35,840
and she has become more than
simply an archaeological find.
238
00:14:35,842 --> 00:14:38,309
DOMINIQUE: Here we are
in Hoyo Negro.
239
00:14:38,311 --> 00:14:39,577
JIM: Yeah.
240
00:14:39,579 --> 00:14:41,079
Wow!
241
00:14:41,081 --> 00:14:43,448
I've always wanted to dive this.
242
00:14:43,450 --> 00:14:46,551
This is about the closest
I'm ever gonna come, I think.
243
00:14:46,553 --> 00:14:50,188
¶ ¶
244
00:14:50,190 --> 00:14:53,858
She's spread over about
a 16-foot span here.
245
00:14:53,860 --> 00:14:57,762
¶ ¶
246
00:14:57,764 --> 00:15:02,800
What I stressed with the divers
was that basically they needed
247
00:15:02,802 --> 00:15:06,337
to remember the personhood
of these bones.
248
00:15:07,908 --> 00:15:08,973
ALBERTO: If you give it a name,
249
00:15:08,975 --> 00:15:13,611
you become more caring
about this skeleton,
250
00:15:13,613 --> 00:15:17,582
and it goes from a skeleton
to becoming a person.
251
00:15:19,786 --> 00:15:23,488
We had a lot of candidates
for names.
252
00:15:23,490 --> 00:15:26,024
We decided to call it Naia.
253
00:15:26,026 --> 00:15:30,695
¶ ¶
254
00:15:30,697 --> 00:15:34,198
JIM: Naiads were water spirits
in Greek mythology.
255
00:15:34,200 --> 00:15:35,733
They were the female spirits
256
00:15:35,735 --> 00:15:38,653
that watched over
small bodies of water,
257
00:15:38,655 --> 00:15:41,472
so it seemed
a very fitting name for her.
258
00:15:43,610 --> 00:15:47,845
NARRATOR: Naia's remains are
found close to Ice Age mammals,
259
00:15:47,847 --> 00:15:49,480
but that isn't enough to prove
260
00:15:49,482 --> 00:15:54,519
that Naia herself
is prehistoric.
261
00:15:54,521 --> 00:15:58,189
JIM: Our goal with Naia
was to collect a specimen
262
00:15:58,191 --> 00:16:00,758
from the skeleton to use
for radiocarbon dating.
263
00:16:00,760 --> 00:16:04,429
¶ ¶
264
00:16:04,431 --> 00:16:06,364
We chose to do one third molar,
265
00:16:06,366 --> 00:16:08,533
because third molars are
often very simply rooted,
266
00:16:08,535 --> 00:16:12,670
and therefore easy to take
out of a skeleton.
267
00:16:12,672 --> 00:16:14,038
DOMINIQUE: There are
a number of problems
268
00:16:14,040 --> 00:16:19,043
inherent in carbon dating, and
those can include contamination.
269
00:16:20,447 --> 00:16:22,080
It was not a foregone conclusion
270
00:16:22,082 --> 00:16:26,284
that we were going to get
a viable date from Naia.
271
00:16:28,521 --> 00:16:32,390
JIM: We ran dates independently
in two laboratories,
272
00:16:32,392 --> 00:16:33,591
fully expecting the dates
273
00:16:33,593 --> 00:16:35,293
to be completely different
from each other,
274
00:16:35,295 --> 00:16:39,614
and it came back
within 15 years.
275
00:16:39,616 --> 00:16:40,598
And between those,
276
00:16:40,600 --> 00:16:46,337
those translate to close
to 12,900 years ago.
277
00:16:49,075 --> 00:16:50,808
It was pretty exciting
to find out,
278
00:16:50,810 --> 00:16:54,812
because only one other skeleton
at that time had dated that old,
279
00:16:54,814 --> 00:16:58,983
and all that there was of
that individual was one bone.
280
00:16:58,985 --> 00:17:01,786
Not even a complete bone.
281
00:17:01,788 --> 00:17:03,888
The fact that Naia's skeleton
was so complete
282
00:17:03,890 --> 00:17:06,524
makes her
an incredibly rare find.
283
00:17:06,526 --> 00:17:09,727
NARRATOR: And as the oldest
near-complete skeleton
284
00:17:09,729 --> 00:17:11,796
ever found in the Americas,
285
00:17:11,798 --> 00:17:16,934
Naia could provide answers
about early humans living here.
286
00:17:16,936 --> 00:17:18,753
But to protect her remains,
287
00:17:18,755 --> 00:17:22,774
the team must first
remove her from the cave.
288
00:17:33,670 --> 00:17:37,205
ALBERTO: So, it's been
six, seven years of adventure,
289
00:17:37,207 --> 00:17:41,109
and although we didn't really
want to take any human remains,
290
00:17:41,111 --> 00:17:43,010
we have to do it to protect it,
291
00:17:43,012 --> 00:17:45,079
and that's kind of what
the day is all about,
292
00:17:45,081 --> 00:17:48,683
protecting Naia and her remains.
293
00:17:48,685 --> 00:17:52,253
NARRATOR: The operation to
recover Naia's fragile skeleton
294
00:17:52,255 --> 00:17:55,423
begins with her skull.
295
00:17:55,425 --> 00:17:57,358
It is fraught with risk.
296
00:17:57,360 --> 00:17:58,926
JIM: Well, we're doing
a pre-dive practice,
297
00:17:58,928 --> 00:18:02,597
or the procedures drill.
298
00:18:02,599 --> 00:18:07,869
NARRATOR: Jim rehearses the
recovery with a replica skull.
299
00:18:07,871 --> 00:18:09,404
JIM: My endeavor was designing
300
00:18:09,406 --> 00:18:13,875
how Naia's bones were
gonna be safely removed.
301
00:18:13,877 --> 00:18:15,076
Your strongest part is here.
302
00:18:15,078 --> 00:18:16,043
SUSAN BIRD: Mm-hmm.
303
00:18:16,045 --> 00:18:17,812
JIM: Your weakest points
are here and here,
304
00:18:17,814 --> 00:18:20,615
so we want to protect them.
305
00:18:20,617 --> 00:18:21,883
This was a big deal.
306
00:18:21,885 --> 00:18:25,319
I mean, imagine, I'm the one
responsible for making sure
307
00:18:25,321 --> 00:18:29,657
that thing doesn't get destroyed
in the collection process,
308
00:18:29,659 --> 00:18:33,094
so I was just a little
on the nervous side.
309
00:18:33,096 --> 00:18:36,597
And just gently, chin first.
310
00:18:36,599 --> 00:18:38,232
SUSAN: Okay.
JIM: And release.
311
00:18:39,536 --> 00:18:42,036
The reason Susan was the one
to handle the bones
312
00:18:42,038 --> 00:18:47,108
had in part to do with the fact
that she had very steady hands,
313
00:18:47,110 --> 00:18:49,343
but she also felt a linkage
314
00:18:49,345 --> 00:18:52,647
to the young woman
who was in the cave.
315
00:18:52,649 --> 00:18:55,817
SUSAN: And I just feel
very connected with her spirit.
316
00:18:55,819 --> 00:18:59,353
I feel like she's been
there a long time
317
00:18:59,355 --> 00:19:02,757
and is ready to go home.
318
00:19:02,759 --> 00:19:05,159
¶ ¶
319
00:19:05,161 --> 00:19:10,665
¶ ¶
320
00:19:10,667 --> 00:19:13,968
ALBERTO: There was one chance,
and we had to get it right.
321
00:19:13,970 --> 00:19:16,370
¶ ¶
322
00:19:16,372 --> 00:19:23,211
¶ ¶
323
00:19:23,213 --> 00:19:25,079
The moment Susan
picked up the skull,
324
00:19:25,081 --> 00:19:29,650
everybody's breathing stopped.
325
00:19:29,652 --> 00:19:32,086
¶ ¶
326
00:19:32,088 --> 00:19:38,292
¶ ¶
327
00:19:38,294 --> 00:19:43,598
JIM: That was a really tense
three hours of waiting,
328
00:19:43,600 --> 00:19:46,534
waiting to see if what would be
in the box when it came up
329
00:19:46,536 --> 00:19:49,871
was a complete skull or
a whole pile of bone fragments.
330
00:19:49,873 --> 00:19:56,077
¶ ¶
331
00:19:56,079 --> 00:19:58,880
Here they come!
332
00:19:58,882 --> 00:19:59,881
My, oh, my.
333
00:19:59,883 --> 00:20:02,350
Okay, Susan's on the left,
Beto's on the right.
334
00:20:02,352 --> 00:20:09,257
¶ ¶
335
00:20:09,259 --> 00:20:10,291
DOMINIQUE: She comes
to the surface,
336
00:20:10,293 --> 00:20:13,594
and you know that
as an archaeologist,
337
00:20:13,596 --> 00:20:16,130
you're never gonna have
another experience like this.
338
00:20:16,132 --> 00:20:19,333
I mean, this is it.
339
00:20:19,335 --> 00:20:21,402
(sighs)
340
00:20:24,507 --> 00:20:26,040
Okay, go ahead.
341
00:20:26,042 --> 00:20:27,808
Okay, she's fine in there.
342
00:20:27,810 --> 00:20:30,311
Nice! Ha.
343
00:20:30,313 --> 00:20:32,680
I remember getting down
and peeking in the end
344
00:20:32,682 --> 00:20:34,849
and seeing a whole skull there,
345
00:20:34,851 --> 00:20:38,886
and tremendous elation
that came from that.
346
00:20:38,888 --> 00:20:39,820
Welcome, Naia!
347
00:20:39,822 --> 00:20:42,590
We got her out and
we got her out whole.
348
00:20:42,592 --> 00:20:44,258
ALBERTO: Jim Chatters,
it's good to meet you.
349
00:20:44,260 --> 00:20:46,327
JIM: Gracias, gracias.
Good job, man.
350
00:20:46,329 --> 00:20:49,597
I've been at this
for 60-plus years,
351
00:20:49,599 --> 00:20:53,968
and that was the top moment
in all that time.
352
00:20:53,970 --> 00:20:55,469
SUSAN: Hey!
353
00:20:55,471 --> 00:20:57,071
JIM: We cried.
354
00:20:57,073 --> 00:21:03,511
¶ ¶
355
00:21:03,513 --> 00:21:05,513
NARRATOR: Naia's remains
give the team
356
00:21:05,515 --> 00:21:07,648
an unprecedented opportunity
357
00:21:07,650 --> 00:21:12,520
to learn about
America's early humans.
358
00:21:12,522 --> 00:21:16,390
A key question is whether Naia
is a direct ancestor
359
00:21:16,392 --> 00:21:20,194
to modern Native Americans.
360
00:21:20,196 --> 00:21:26,133
In a replica of her skeleton,
Jim looks for clues.
361
00:21:26,135 --> 00:21:28,102
JIM: The characteristics
that jumped out at me
362
00:21:28,104 --> 00:21:32,273
was the very distinct angularity
to the back of her skull,
363
00:21:32,275 --> 00:21:36,377
and the tendency for her face
to project forward.
364
00:21:36,379 --> 00:21:38,045
NARRATOR: These are not
common features
365
00:21:38,047 --> 00:21:40,114
of modern Native Americans.
366
00:21:40,116 --> 00:21:42,883
JIM: The contrast with more
recent Native American skulls
367
00:21:42,885 --> 00:21:44,885
represented by these casts here.
368
00:21:44,887 --> 00:21:45,786
Here's a female.
369
00:21:45,788 --> 00:21:49,390
You can see a much more
rounded skull.
370
00:21:49,392 --> 00:21:51,258
The face, in a similar position,
371
00:21:51,260 --> 00:21:53,311
is much more
straight up and down.
372
00:21:53,313 --> 00:21:54,395
NARRATOR: When the team turns
373
00:21:54,397 --> 00:21:57,398
to facial reconstruction
technology,
374
00:21:57,400 --> 00:22:00,134
the mystery deepens.
375
00:22:00,136 --> 00:22:05,306
JIM: What we got, we went
from the printed skull here,
376
00:22:05,308 --> 00:22:08,909
and then this is how
she turned out.
377
00:22:08,911 --> 00:22:13,648
¶ ¶
378
00:22:13,650 --> 00:22:16,984
I didn't expect her
to look like she did.
379
00:22:16,986 --> 00:22:21,288
She almost looks like
a South African bushman
380
00:22:21,290 --> 00:22:26,927
from the Kalahari Desert, or
someone out of Southeast Asia.
381
00:22:26,929 --> 00:22:30,498
Her eyes are wider set,
her nose is broader,
382
00:22:30,500 --> 00:22:33,601
so those are all things
that were different
383
00:22:33,603 --> 00:22:35,936
from what I'm used to.
384
00:22:35,938 --> 00:22:37,805
DOMINIQUE:
There's a mystery then:
385
00:22:37,807 --> 00:22:42,610
If she appears to be
so different from the ancestors
386
00:22:42,612 --> 00:22:47,481
of modern Native Americans,
where did she come from?
387
00:22:48,885 --> 00:22:53,721
NARRATOR: To find out,
the team tests Naia's DNA.
388
00:22:57,727 --> 00:22:58,959
JIM: When I got
the result back,
389
00:22:58,961 --> 00:23:01,595
I was very happy
that we got a result,
390
00:23:01,597 --> 00:23:03,998
but as happy as I was
to get the result,
391
00:23:04,000 --> 00:23:08,002
it was not the result
I expected.
392
00:23:08,004 --> 00:23:11,539
What it showed was that although
Naia's skull seemed different
393
00:23:11,541 --> 00:23:13,307
from modern Native Americans,
394
00:23:13,309 --> 00:23:15,876
they still shared
a genetic background.
395
00:23:15,878 --> 00:23:19,680
They shared the same heritage.
396
00:23:19,682 --> 00:23:22,049
NARRATOR:
So, Naia is an ancestor
397
00:23:22,051 --> 00:23:24,919
of modern Native Americans.
398
00:23:24,921 --> 00:23:27,388
Now, the age of her skeleton,
399
00:23:27,390 --> 00:23:29,890
dated to the very end
of the Ice Age,
400
00:23:29,892 --> 00:23:31,525
propels her into the center
401
00:23:31,527 --> 00:23:35,262
of one of the hottest
controversies in science.
402
00:23:35,264 --> 00:23:41,001
How did she and her people
get to the American continent?
403
00:23:41,003 --> 00:23:42,570
JIM: So, part of the question
about Naia
404
00:23:42,572 --> 00:23:47,508
was can she help contribute
to an answer to that question?
405
00:23:54,000 --> 00:23:56,434
¶ ¶
406
00:23:56,436 --> 00:24:03,441
¶ ¶
407
00:24:03,443 --> 00:24:05,709
NARRATOR: For decades,
experts agreed
408
00:24:05,711 --> 00:24:11,882
on how the first humans
migrated to the Americas.
409
00:24:11,884 --> 00:24:16,520
JAMES DELGADO: In school,
studying archaeology,
410
00:24:16,522 --> 00:24:20,741
I heard a great deal about
the Bering land bridge.
411
00:24:20,743 --> 00:24:26,530
¶ ¶
412
00:24:26,532 --> 00:24:27,998
During the last Ice Age,
413
00:24:28,000 --> 00:24:33,020
huge ice sheets blocked the land
route from Siberia to Alaska.
414
00:24:33,022 --> 00:24:36,841
But when the ice thaws
around 13,000 years ago,
415
00:24:36,843 --> 00:24:39,643
which is when Naia is living
in the Yucatán,
416
00:24:39,645 --> 00:24:44,081
it becomes possible for humans
to walk into America,
417
00:24:44,083 --> 00:24:48,552
and a group previously known as
the Clovis people do just that.
418
00:24:50,423 --> 00:24:52,423
LOREN DAVIS: The Clovis First
model is that people came
419
00:24:52,425 --> 00:24:54,959
into the Americas
by way of migrating
420
00:24:54,961 --> 00:24:59,530
through an ice-free corridor,
exiting south of the ice,
421
00:24:59,532 --> 00:25:03,968
hunting megafauna
like mammoths and bison,
422
00:25:03,970 --> 00:25:06,737
using a very specific
kind of technology
423
00:25:06,739 --> 00:25:10,674
known as a Clovis spear point.
424
00:25:10,676 --> 00:25:14,345
JAMES: That view that this
Clovis group were the people
425
00:25:14,347 --> 00:25:16,580
that had come across
the Bering Straits
426
00:25:16,582 --> 00:25:19,617
and were the ancestors
of modern Native Americans
427
00:25:19,619 --> 00:25:23,754
became so fixed
in archaeological orthodoxy
428
00:25:23,756 --> 00:25:27,992
that to suggest an earlier date
and other migrations
429
00:25:27,994 --> 00:25:30,895
was scientific heresy.
430
00:25:32,665 --> 00:25:34,999
NARRATOR: The question is,
do Naia's people
431
00:25:35,001 --> 00:25:40,004
travel to the Yucatán through
the opening ice-free corridor,
432
00:25:40,006 --> 00:25:41,839
or some other way?
433
00:25:41,841 --> 00:25:46,243
¶ ¶
434
00:25:46,245 --> 00:25:48,345
LOREN: The problem with
explaining everything
435
00:25:48,347 --> 00:25:50,281
as an interior migration,
436
00:25:50,283 --> 00:25:53,017
that's just not an explanation
that accounts for the facts,
437
00:25:53,019 --> 00:25:55,819
and the facts are that people
are south of the ice
438
00:25:55,821 --> 00:26:00,090
before this
ice-free corridor opens.
439
00:26:00,092 --> 00:26:04,395
The earliest sites, for example,
are actually in South America.
440
00:26:04,397 --> 00:26:07,598
So, there's one in Peru
called Huaca Prieta,
441
00:26:07,600 --> 00:26:09,233
and there's another one in Chile
442
00:26:09,235 --> 00:26:11,135
known as Monte Verde.
443
00:26:13,573 --> 00:26:16,440
Stone tools, bones and charcoal
from these sites
444
00:26:16,442 --> 00:26:18,208
show that humans
were in the Americas
445
00:26:18,210 --> 00:26:21,445
at least 14,500 years ago,
446
00:26:21,447 --> 00:26:24,782
more than 1,000 years
before the ice melts.
447
00:26:26,452 --> 00:26:29,853
NARRATOR: So, if ice is
blocking the land route,
448
00:26:29,855 --> 00:26:33,223
how do these earliest
Americans arrive?
449
00:26:33,225 --> 00:26:35,459
LOREN: They must have come here
another way,
450
00:26:35,461 --> 00:26:38,495
so that's why we're interested
in looking on the coast,
451
00:26:38,497 --> 00:26:41,231
'cause that is
the easiest explanation
452
00:26:41,233 --> 00:26:44,001
to explain how we can get
people south of the ice
453
00:26:44,003 --> 00:26:46,570
before this ice-free corridor
opens up.
454
00:26:47,974 --> 00:26:52,376
NARRATOR: In 1997, scientists
begin to uncover evidence
455
00:26:52,378 --> 00:26:58,649
of very early human habitation
in this remote valley in Idaho.
456
00:26:58,651 --> 00:27:00,718
LOREN: As people were migrating
south along the coast,
457
00:27:00,720 --> 00:27:02,119
they would have had
ice to their left
458
00:27:02,121 --> 00:27:03,854
and the ocean to their right,
459
00:27:03,856 --> 00:27:07,758
and they would have encountered
the Columbia River eventually.
460
00:27:07,760 --> 00:27:10,260
They may have decided to just
simply take a left-hand turn
461
00:27:10,262 --> 00:27:11,595
south of the ice,
462
00:27:11,597 --> 00:27:14,999
and penetrate into North America
at that point.
463
00:27:15,001 --> 00:27:16,800
And if they kept going upriver,
464
00:27:16,802 --> 00:27:21,372
they would have made their way
here to Cooper's Ferry.
465
00:27:21,374 --> 00:27:24,908
NARRATOR: Loren and his
students search for stone tools
466
00:27:24,910 --> 00:27:29,613
that migrating humans
may have left behind.
467
00:27:29,615 --> 00:27:30,781
LOREN: Well, if this site
was old enough,
468
00:27:30,783 --> 00:27:34,184
we might actually find evidence
of Clovis peoples,
469
00:27:34,186 --> 00:27:39,289
but, sort of to my surprise,
we didn't see that at all.
470
00:27:39,291 --> 00:27:42,259
Did you see this thing?
471
00:27:42,261 --> 00:27:43,794
What we did find instead
472
00:27:43,796 --> 00:27:45,763
were these other
kind of spear points,
473
00:27:45,765 --> 00:27:50,134
and these are known
as stemmed points.
474
00:27:50,136 --> 00:27:53,737
Stemmed points look very
different than Clovis points.
475
00:27:53,739 --> 00:27:57,741
They have a little, small
rectangular tab at the bottom.
476
00:27:57,743 --> 00:27:59,510
That just made it very clear
477
00:27:59,512 --> 00:28:01,679
that we have some other
kind of cultural pattern
478
00:28:01,681 --> 00:28:04,948
that's present at the site,
at the same time
479
00:28:04,950 --> 00:28:09,420
people were making
Clovis artifacts somewhere else.
480
00:28:09,422 --> 00:28:12,122
When we first found these,
I really didn't have any idea
481
00:28:12,124 --> 00:28:16,193
how old they were,
so that was a big question.
482
00:28:17,763 --> 00:28:21,265
Radiocarbon dating showed us
that points like these
483
00:28:21,267 --> 00:28:24,968
are 13,000 years old.
484
00:28:24,970 --> 00:28:29,606
Some of them were older,
14,000, 14,500.
485
00:28:29,608 --> 00:28:32,376
And it just blew our minds
that this technology
486
00:28:32,378 --> 00:28:36,947
could actually be as old as
Clovis, and then even earlier.
487
00:28:36,949 --> 00:28:39,750
NARRATOR: Some challenged this,
but if those dates are correct,
488
00:28:39,752 --> 00:28:43,020
that's 1,000 years before
the ice-free corridor,
489
00:28:43,022 --> 00:28:46,223
and at least 2,000
before Naia's time.
490
00:28:46,225 --> 00:28:48,225
How might these people arrive?
491
00:28:48,227 --> 00:28:50,160
Are the stemmed points a clue?
492
00:28:50,162 --> 00:28:51,795
LOREN: The only other place
that we find artifacts
493
00:28:51,797 --> 00:28:54,865
that look like this during
the end of the last Ice Age
494
00:28:54,867 --> 00:28:56,600
are in the northern part
of Japan,
495
00:28:56,602 --> 00:28:59,503
on the island of Hokkaido.
496
00:28:59,505 --> 00:29:02,206
NARRATOR: Loren believes this
shows how early people
497
00:29:02,208 --> 00:29:06,143
traveled into the Americas
from the Far East,
498
00:29:06,145 --> 00:29:09,813
via the Ice Age
coastline and rivers.
499
00:29:09,815 --> 00:29:11,882
LOREN: If we imagine that people
might have been able to come
500
00:29:11,884 --> 00:29:15,319
along the coastline,
along the Northern Pacific,
501
00:29:15,321 --> 00:29:19,123
into the Americas, we don't
really need to look much farther
502
00:29:19,125 --> 00:29:22,326
than Japan,
the Russian Far East,
503
00:29:22,328 --> 00:29:26,063
and they show us that there's
a population already in place.
504
00:29:26,065 --> 00:29:27,765
They are on the doorstep,
505
00:29:27,767 --> 00:29:32,603
waiting to migrate their way
into the Americas.
506
00:29:32,605 --> 00:29:34,204
JAMES: It didn't mean
that you'd have to sail
507
00:29:34,206 --> 00:29:38,375
all the way across the Pacific
or across the Atlantic.
508
00:29:38,377 --> 00:29:41,812
You just island-hopped
from bay to bay,
509
00:29:41,814 --> 00:29:46,183
making your way,
sometimes over a generation.
510
00:29:46,185 --> 00:29:47,684
LOREN: As new sites
are being discovered
511
00:29:47,686 --> 00:29:50,287
that show us that people
are south of the ice
512
00:29:50,289 --> 00:29:53,490
before an ice-free
corridor opens,
513
00:29:53,492 --> 00:29:57,961
that requires us
to really rethink things.
514
00:29:57,963 --> 00:30:00,764
NARRATOR: To truly understand
human migration,
515
00:30:00,766 --> 00:30:04,034
Loren needs to explore
the Ice Age coastline.
516
00:30:04,036 --> 00:30:08,872
The problem is, it's now
more than 400 feet underwater.
517
00:30:08,874 --> 00:30:10,674
LOREN: How can we find
the evidence out there
518
00:30:10,676 --> 00:30:12,409
where it likely exists?
519
00:30:12,411 --> 00:30:14,178
And that takes us offshore,
520
00:30:14,180 --> 00:30:16,280
and we need to look
beneath the waves.
521
00:30:26,375 --> 00:30:28,108
LOREN: It's important
to understand the coast
522
00:30:28,110 --> 00:30:29,776
from an archaeological
perspective,
523
00:30:29,778 --> 00:30:32,479
because it could be the place
that holds evidence
524
00:30:32,481 --> 00:30:35,782
for the earliest peoples
to come into the Americas.
525
00:30:37,353 --> 00:30:39,720
NARRATOR: Loren Davis is
searching for evidence
526
00:30:39,722 --> 00:30:42,823
that early settlers
use a coastal route
527
00:30:42,825 --> 00:30:45,125
into the Americas,
528
00:30:45,127 --> 00:30:47,794
but he's not looking
at today's coastline
529
00:30:47,796 --> 00:30:49,897
for a very good reason.
530
00:30:52,301 --> 00:30:54,635
LOREN: During the Ice Age,
the coast of the continent
531
00:30:54,637 --> 00:30:58,205
looked very different
to how it does now.
532
00:30:58,207 --> 00:30:59,506
When the ice melted,
533
00:30:59,508 --> 00:31:03,710
all that trapped water raised
sea levels by over 400 feet,
534
00:31:03,712 --> 00:31:06,847
so any evidence of early peoples
living on the coast
535
00:31:06,849 --> 00:31:10,217
are now deep underwater.
536
00:31:10,219 --> 00:31:13,554
NARRATOR: And that means
searching below the waves,
537
00:31:13,556 --> 00:31:16,490
30 miles out to sea.
538
00:31:18,327 --> 00:31:21,094
LOREN: Getting on this ship was
a real breakthrough for us,
539
00:31:21,096 --> 00:31:23,197
'cause it allowed us
to then go out
540
00:31:23,199 --> 00:31:27,568
and ground truth
our theoretical ideas.
541
00:31:27,570 --> 00:31:31,238
WOMAN: We are off the northeast
of Heceta Bank,
542
00:31:31,240 --> 00:31:35,976
which is off
the central coast of Oregon.
543
00:31:35,978 --> 00:31:38,812
LOREN: We went out to the very
edge of the ancient coastline,
544
00:31:38,814 --> 00:31:39,980
so these are areas
545
00:31:39,982 --> 00:31:44,384
that are about 130 meters
below modern sea level.
546
00:31:44,386 --> 00:31:46,119
Oh, man!
547
00:31:46,121 --> 00:31:48,088
Went off a cliff!
548
00:31:48,090 --> 00:31:49,122
(woman chuckles)
549
00:31:50,659 --> 00:31:53,260
NARRATOR: Loren one day
hopes to find evidence
550
00:31:53,262 --> 00:31:55,462
of prehistoric
human settlements
551
00:31:55,464 --> 00:31:57,664
on this ancient coastline.
552
00:31:57,666 --> 00:32:00,834
The first step is to build
an accurate picture
553
00:32:00,836 --> 00:32:05,906
of the hidden Ice Age landscape
below the waves.
554
00:32:05,908 --> 00:32:07,507
LOREN: As sea level comes up,
555
00:32:07,509 --> 00:32:09,876
it brings a lot of sediment
with it,
556
00:32:09,878 --> 00:32:14,314
and it will bury the ancient
landscape that was once there,
557
00:32:14,316 --> 00:32:16,049
so this obscures our view.
558
00:32:16,051 --> 00:32:17,251
We really need a technique
559
00:32:17,253 --> 00:32:20,487
that allows us to see
into the seafloor,
560
00:32:20,489 --> 00:32:23,890
and one of the tools that we use
is called a sub-bottom profiler,
561
00:32:23,892 --> 00:32:28,595
and what this does is it sends
a sound pulse into the seafloor,
562
00:32:28,597 --> 00:32:31,298
and it will reflect back
an acoustic signal
563
00:32:31,300 --> 00:32:36,436
that it then turns into
sort of a depth map.
564
00:32:36,438 --> 00:32:41,675
MAN: Could we track a line
bearing 317 at 0.4?
565
00:32:43,846 --> 00:32:45,779
NARRATOR:
Merging the deep sea scans
566
00:32:45,781 --> 00:32:48,048
with data from computer models
567
00:32:48,050 --> 00:32:51,585
reveals a world not seen
for millennia:
568
00:32:51,587 --> 00:32:55,689
the shoreline
of Ice Age America.
569
00:32:57,159 --> 00:32:58,592
LOREN: If we were
to lower the ocean
570
00:32:58,594 --> 00:33:02,129
down to about 13,000 years ago,
the position where it was then,
571
00:33:02,131 --> 00:33:05,365
we would see a really
different coastline.
572
00:33:08,604 --> 00:33:10,871
We would be able to see
river valleys,
573
00:33:10,873 --> 00:33:14,708
we would see embayments, we
would see a low mountain range.
574
00:33:14,710 --> 00:33:16,543
It would be
a broad coastal plain
575
00:33:16,545 --> 00:33:17,944
that looks really different
576
00:33:17,946 --> 00:33:20,814
than the rugged,
mountainous coastline
577
00:33:20,816 --> 00:33:24,551
of today's central coast.
578
00:33:24,553 --> 00:33:30,290
JAMES: That's a landscape with
estuaries full of marine life,
579
00:33:30,292 --> 00:33:34,194
as well as seabirds and animals.
580
00:33:34,196 --> 00:33:40,267
And with that, we would see
this lost world,
581
00:33:40,269 --> 00:33:42,803
the Americas as they were
582
00:33:42,805 --> 00:33:46,606
at the time of initial
human settlement.
583
00:33:46,608 --> 00:33:51,078
¶ ¶
584
00:33:51,080 --> 00:33:54,381
LOREN: This story of ancient
coastlines under lower sea level
585
00:33:54,383 --> 00:33:57,184
associated with the last Ice Age
is not just an Oregon story.
586
00:33:57,186 --> 00:34:00,587
This is a story that
happens everywhere.
587
00:34:00,589 --> 00:34:02,022
NARRATOR:
Similar investigations
588
00:34:02,024 --> 00:34:06,259
are being conducted
all along the Pacific coast.
589
00:34:08,430 --> 00:34:09,596
LOREN: As you go farther south,
590
00:34:09,598 --> 00:34:11,498
San Francisco would
have been an area
591
00:34:11,500 --> 00:34:14,634
that isn't on the coast
in the past.
592
00:34:14,636 --> 00:34:16,002
That is, lowered sea level
593
00:34:16,004 --> 00:34:19,172
would have taken it much farther
away from its modern position,
594
00:34:19,174 --> 00:34:23,410
so San Francisco would have been
really sort of an inland valley.
595
00:34:23,412 --> 00:34:25,879
¶ ¶
596
00:34:25,881 --> 00:34:32,753
¶ ¶
597
00:34:32,755 --> 00:34:34,121
NARRATOR:
Having accurate mapping
598
00:34:34,123 --> 00:34:38,125
of North America's Ice Age
coastline now allows Loren
599
00:34:38,127 --> 00:34:42,929
to narrow his search for signs
of early human habitation.
600
00:34:42,931 --> 00:34:46,933
LOREN: So, if I'm a traditional
hunter-gatherer, fisher person,
601
00:34:46,935 --> 00:34:49,403
and I'm living
on an ancient coastline,
602
00:34:49,405 --> 00:34:52,639
where are the hot spots?
603
00:34:52,641 --> 00:34:55,842
Where are the places that are
gonna take care of me the best?
604
00:34:55,844 --> 00:34:58,378
And the estuaries
are really, really
605
00:34:58,380 --> 00:35:00,147
important places for people.
606
00:35:00,149 --> 00:35:02,549
I mean, there's more calories
per square meter in an estuary
607
00:35:02,551 --> 00:35:05,819
than almost any other place
on the coast.
608
00:35:05,821 --> 00:35:08,755
NARRATOR: What really happened
remains unclear,
609
00:35:08,757 --> 00:35:12,626
but Loren and others continue
to explore, debate
610
00:35:12,628 --> 00:35:14,961
and seek new clues.
611
00:35:14,963 --> 00:35:19,499
LOREN: Archaeology works
by making discoveries.
612
00:35:19,501 --> 00:35:23,737
In time, my bet is on that these
discoveries are going to be made
613
00:35:23,739 --> 00:35:26,606
up and down the Pacific coast
of the Americas.
614
00:35:26,608 --> 00:35:30,510
JIM: This is more
anatomical position here.
615
00:35:30,512 --> 00:35:33,880
NARRATOR: When Naia dies,
13,000 years ago,
616
00:35:33,882 --> 00:35:36,883
early humans are arriving
in North America
617
00:35:36,885 --> 00:35:39,853
via the ice-free corridor,
618
00:35:39,855 --> 00:35:42,422
and the place she is found
in the Yucatán
619
00:35:42,424 --> 00:35:43,690
is only a few miles
620
00:35:43,692 --> 00:35:46,827
from the Ice Age coastline.
621
00:35:46,829 --> 00:35:50,464
So, which route do
Naia's people take?
622
00:35:51,867 --> 00:35:56,736
Jim hopes to find clues
in Naia's remains.
623
00:35:56,738 --> 00:36:00,040
JIM: Here we're looking at
a micro-CT scan.
624
00:36:01,577 --> 00:36:03,176
You see one little stress line
right there.
625
00:36:03,178 --> 00:36:05,512
See that little line
right along,
626
00:36:05,514 --> 00:36:09,382
right near the junction
with the dentine?
627
00:36:09,384 --> 00:36:12,519
NARRATOR: He's looking for
telltale signs of stress
628
00:36:12,521 --> 00:36:15,622
from her lifestyle
and environment.
629
00:36:15,624 --> 00:36:18,725
JIM: The other place we look is
in the long bones
630
00:36:18,727 --> 00:36:21,561
and how they grow.
631
00:36:21,563 --> 00:36:23,630
Here we're looking at
Naia's thigh bone,
632
00:36:23,632 --> 00:36:24,931
which is the longest bone
633
00:36:24,933 --> 00:36:30,237
and therefore the one that's
gonna give us the most detail.
634
00:36:30,239 --> 00:36:31,771
See these lines?
635
00:36:31,773 --> 00:36:35,742
These are the places where
growth has been interrupted,
636
00:36:35,744 --> 00:36:38,645
and then begun again.
637
00:36:40,616 --> 00:36:43,750
One, two, three,
four, five, six.
638
00:36:43,752 --> 00:36:47,621
Two, three, four, five,
six years we can see.
639
00:36:47,623 --> 00:36:50,223
And the spacing
of those lines in Naia
640
00:36:50,225 --> 00:36:52,959
suggests that she had
a protein deficiency
641
00:36:52,961 --> 00:36:56,963
during one season of every year.
642
00:36:56,965 --> 00:37:01,501
DOMINIQUE: And so she lived
a kind of feast-and-famine life.
643
00:37:01,503 --> 00:37:05,705
¶ ¶
644
00:37:05,707 --> 00:37:07,874
JIM: Seeing that Naia
had protein deficiency
645
00:37:07,876 --> 00:37:09,809
during some times of the year
646
00:37:09,811 --> 00:37:12,646
raises the question of why
was she protein deficient
647
00:37:12,648 --> 00:37:15,248
if she lived so close
to the sea?
648
00:37:18,053 --> 00:37:20,487
DOMINIQUE: There's fish,
there are crustaceans.
649
00:37:20,489 --> 00:37:23,990
The sea is a plentiful place.
650
00:37:23,992 --> 00:37:26,726
JIM: Nothing we're seeing
in the evidence for her diet
651
00:37:26,728 --> 00:37:28,995
is consistent with
being marine-adapted.
652
00:37:28,997 --> 00:37:33,567
It is quite consistent with
being strictly terrestrial.
653
00:37:33,569 --> 00:37:38,672
Her people were not
adapted to the coast.
654
00:37:38,674 --> 00:37:41,708
DOMINIQUE: Really what it
suggests is that she was among
655
00:37:41,710 --> 00:37:44,411
these highly mobile
hunter-gatherers
656
00:37:44,413 --> 00:37:47,614
who were heavily reliant
on a successful hunt,
657
00:37:47,616 --> 00:37:53,386
their ability to hunt and to
kill and to consume megafauna.
658
00:37:53,388 --> 00:37:55,121
And the fact that she
appears unable to fish
659
00:37:55,123 --> 00:37:58,658
or make use of marine proteins,
that really doesn't make sense
660
00:37:58,660 --> 00:38:00,460
if her people had traveled
to the Americas
661
00:38:00,462 --> 00:38:02,762
via a coastal highway.
662
00:38:04,466 --> 00:38:07,734
JAMES: The most dangerous thing
in science is to be disappointed
663
00:38:07,736 --> 00:38:10,203
when the evidence doesn't
support your theory.
664
00:38:10,205 --> 00:38:12,272
So when Naia was found,
given her age,
665
00:38:12,274 --> 00:38:14,975
it was like, "Wow! She had to be
a coastal person."
666
00:38:14,977 --> 00:38:18,878
Well, that doesn't show up
in her bones.
667
00:38:18,880 --> 00:38:22,082
JIM: While she doesn't disprove
the coastal migration theory,
668
00:38:22,084 --> 00:38:25,452
she certainly
does not support it.
669
00:38:25,454 --> 00:38:27,554
NARRATOR: But that doesn't
rule out others coming
670
00:38:27,556 --> 00:38:33,760
via the coastal route at least
2,000 years before her time.
671
00:38:33,762 --> 00:38:36,496
JAMES: It's just the most
fascinating puzzle.
672
00:38:36,498 --> 00:38:39,966
I think it's likely that there
were multiple migrations,
673
00:38:39,968 --> 00:38:43,803
following different routes,
over thousands of years.
674
00:38:43,805 --> 00:38:47,240
NARRATOR: As for Naia,
we are still finding out more
675
00:38:47,242 --> 00:38:50,877
about her life and death.
676
00:38:50,879 --> 00:38:54,014
JIM: The hardest ones to work
with are the young people.
677
00:38:54,016 --> 00:38:55,782
You think about
a life not lived,
678
00:38:55,784 --> 00:38:58,752
but you also think about
the impact of the loss
679
00:38:58,754 --> 00:39:02,989
of that individual on their
parents, their siblings,
680
00:39:02,991 --> 00:39:05,091
their young spouses.
681
00:39:05,093 --> 00:39:07,694
NARRATOR: Now they want
to piece together the clues
682
00:39:07,696 --> 00:39:10,497
to understand what may
have happened to Naia
683
00:39:10,499 --> 00:39:15,268
in the Yucatán cave system
13,000 years ago.
684
00:39:20,842 --> 00:39:27,047
¶ ¶
685
00:39:27,049 --> 00:39:30,016
JIM: When we're working with
ancient human skeletons,
686
00:39:30,018 --> 00:39:34,020
we're dealing with
the ultimate cold cases.
687
00:39:34,022 --> 00:39:37,290
NARRATOR: Jim Chatters'
forensic examinations reveal
688
00:39:37,292 --> 00:39:42,696
an injury from which Naia
would not have recovered.
689
00:39:42,698 --> 00:39:45,699
JIM: We know from her pelvis,
690
00:39:45,701 --> 00:39:48,868
she struck the front
of her pelvis here,
691
00:39:48,870 --> 00:39:51,371
and it broke away
the pubic bones on both sides.
692
00:39:51,373 --> 00:39:55,408
These jagged breaks that you see
here are green bone fractures.
693
00:39:55,410 --> 00:39:57,544
They're the kind of breaks
that fresh bone gets,
694
00:39:57,546 --> 00:39:59,746
not old, dead bone gets.
695
00:39:59,748 --> 00:40:01,181
This was a serious accident.
696
00:40:01,183 --> 00:40:04,050
It is not easy
to break your pelvis;
697
00:40:04,052 --> 00:40:06,586
not to shatter it like that.
698
00:40:07,956 --> 00:40:09,956
NARRATOR: To determine
what could have caused
699
00:40:09,958 --> 00:40:11,858
Naia's fatal injury,
700
00:40:11,860 --> 00:40:15,161
Dominique Rissolo and Jim
attempt to retrace
701
00:40:15,163 --> 00:40:19,432
her footsteps in the 3D replica
of the cave.
702
00:40:19,434 --> 00:40:20,967
DOMINIQUE: It's impossible
not to wonder
703
00:40:20,969 --> 00:40:23,870
why Naia was in the cave.
704
00:40:26,074 --> 00:40:29,342
Hoyo Negro had a pool of water
in the bottom.
705
00:40:29,344 --> 00:40:31,411
Was she there for water?
706
00:40:33,615 --> 00:40:36,950
This would have been the route
that she would have walked.
707
00:40:36,952 --> 00:40:38,518
JIM: This is the most likely way
she came in.
708
00:40:38,520 --> 00:40:43,323
The closest entrance is
about 2,000 feet behind us.
709
00:40:43,325 --> 00:40:45,792
(heavy breathing)
710
00:40:45,794 --> 00:40:50,363
(heavy breathing)
711
00:40:50,365 --> 00:40:54,167
Imagine she is deep in the cave
and she's lost her way,
712
00:40:54,169 --> 00:40:58,304
which would be easy
in these caverns.
713
00:40:58,306 --> 00:41:00,874
These tunnels,
they join and they separate,
714
00:41:00,876 --> 00:41:02,041
and join and separate,
715
00:41:02,043 --> 00:41:05,845
and getting lost would be
a very easy thing to do.
716
00:41:05,847 --> 00:41:08,314
(heavy breathing)
717
00:41:08,316 --> 00:41:10,316
You can turn to the left,
718
00:41:10,318 --> 00:41:13,386
and work your way
over some boulders.
719
00:41:15,157 --> 00:41:18,224
DOMINIQUE: Was she being pursued
by another animal
720
00:41:18,226 --> 00:41:20,527
inside the cave?
721
00:41:20,529 --> 00:41:23,530
She knows there are large,
dangerous animals there.
722
00:41:23,532 --> 00:41:30,170
(heavy breathing)
723
00:41:30,172 --> 00:41:32,305
DOMINIQUE: So, kind of climbing
over these rocks
724
00:41:32,307 --> 00:41:33,840
so close to the edge.
725
00:41:33,842 --> 00:41:38,478
You know, maybe trying to find
a way around the pit?
726
00:41:38,480 --> 00:41:41,681
JIM: Otherwise we can't get her
over to where she fell.
727
00:41:41,683 --> 00:41:43,183
(heavy breathing)
728
00:41:43,185 --> 00:41:45,051
Eventually her light's
gonna go out,
729
00:41:45,053 --> 00:41:46,686
and she's wandering in the dark.
730
00:41:46,688 --> 00:41:48,454
(heavy breathing)
731
00:41:48,456 --> 00:41:55,295
And suddenly she takes one final
step, and the bottom falls away.
732
00:41:55,297 --> 00:41:56,896
Whoa!
733
00:42:01,036 --> 00:42:05,305
From the floor of that tunnel to
the surface of the water below
734
00:42:05,307 --> 00:42:08,508
was right about 100 feet.
735
00:42:08,510 --> 00:42:10,577
30 meters.
736
00:42:10,579 --> 00:42:12,078
And if you look
straight down the rim...
737
00:42:12,080 --> 00:42:13,413
DOMINIQUE: Yeah, yeah,
yeah, yeah, yeah.
738
00:42:13,415 --> 00:42:14,881
JIM: She's right down there.
DOMINIQUE: Oh, my goodness!
739
00:42:14,883 --> 00:42:18,651
JIM: So you fall--Okay, now,
Joel, just swing straight down.
740
00:42:18,653 --> 00:42:20,253
From where her body was,
it looks like she probably
741
00:42:20,255 --> 00:42:24,457
went through the water and
smacked the rocks down below it.
742
00:42:24,459 --> 00:42:26,226
I imagine she was
knocked unconscious
743
00:42:26,228 --> 00:42:28,962
and didn't know a thing
after that.
744
00:42:30,465 --> 00:42:32,999
NARRATOR: What happens next
sets in motion
745
00:42:33,001 --> 00:42:35,535
an extraordinary
series of events,
746
00:42:35,537 --> 00:42:41,140
which preserved Naia's remains
for the next 13,000 years.
747
00:42:42,711 --> 00:42:44,577
DOMINIQUE: And what we see,
of course,
748
00:42:44,579 --> 00:42:46,980
is global sea level rise,
749
00:42:46,982 --> 00:42:50,583
and those rising sea levels
are pushing the fresh water
750
00:42:50,585 --> 00:42:54,187
that lies under
the peninsula up.
751
00:42:54,189 --> 00:42:55,655
And this chamber is flooding,
752
00:42:55,657 --> 00:42:57,690
and it's flooding
surprisingly fast.
753
00:42:57,692 --> 00:43:02,495
Over a few thousand years
we see a dry cave,
754
00:43:02,497 --> 00:43:04,864
to a completely flooded one.
755
00:43:04,866 --> 00:43:08,434
It's a really rapid and
incredible transformation.
756
00:43:10,038 --> 00:43:14,007
JIM: That sealed the cave off.
757
00:43:14,009 --> 00:43:16,175
And it became
absolutely isolated
758
00:43:16,177 --> 00:43:19,779
from the rest of the world.
759
00:43:19,781 --> 00:43:21,281
It wasn't until cave divers,
760
00:43:21,283 --> 00:43:24,784
just exploring for
the sheer joy of it,
761
00:43:24,786 --> 00:43:27,320
happened upon
this huge black hole.
762
00:43:27,322 --> 00:43:30,990
¶ ¶
763
00:43:30,992 --> 00:43:33,393
NARRATOR: For Dominique
and the team of scientists
764
00:43:33,395 --> 00:43:38,865
studying her, Naia's story
is not yet complete.
765
00:43:38,867 --> 00:43:43,202
JIM: She comes to us
forward in time as a messenger,
766
00:43:43,204 --> 00:43:47,874
and tells us of the life
of people lost so long ago.
767
00:43:50,378 --> 00:43:52,679
DOMINIQUE: We know very little
about her culture.
768
00:43:52,681 --> 00:43:55,915
We certainly don't know
what language she spoke.
769
00:43:55,917 --> 00:43:58,918
We don't have stone tools,
we don't have artifacts.
770
00:43:58,920 --> 00:44:01,821
Those have yet to be discovered.
771
00:44:03,391 --> 00:44:06,859
LOREN: One of these days I hope
that we actually find artifacts
772
00:44:06,861 --> 00:44:09,696
that are of very clear
human origin.
773
00:44:09,698 --> 00:44:11,164
I hope that we find information
774
00:44:11,166 --> 00:44:13,433
about the foods
that they're eating.
775
00:44:13,435 --> 00:44:15,435
We may even get as lucky
as to find something
776
00:44:15,437 --> 00:44:19,639
that reflects the personal life
of somebody.
777
00:44:19,641 --> 00:44:21,908
To me, it's only
a matter of time.
778
00:44:21,910 --> 00:44:23,276
Captioned by
Side Door Media Services