Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:01,060 --> 00:00:04,319
Sometimes the world feels...hmm, boring.
2
00:00:05,020 --> 00:00:11,580
We've visited all the remote islands, conquered the Arctic, and penetrated the deepest jungles.
3
00:00:12,420 --> 00:00:15,200
But there is still one place to explore.
4
00:00:15,840 --> 00:00:22,960
It's a wet and deadly desert inhabited by mysterious creatures living in total darkness.
5
00:00:23,420 --> 00:00:24,980
The deep sea.
6
00:00:25,240 --> 00:00:26,560
Let's dive down.
7
00:00:26,720 --> 00:00:35,420
[♫ Catchy Intro Jingle ♫]
8
00:00:37,000 --> 00:00:39,980
When we look at the sheer scale of the Earth's oceans,
9
00:00:39,980 --> 00:00:44,700
it's hard to believe that less than 2% of all biomass on Earth lives here.
10
00:00:45,400 --> 00:00:52,420
And of that small percentage, around 90% is located close to the surface in the first 200 meters.
11
00:00:53,480 --> 00:00:55,680
This is where we begin our journey.
12
00:00:56,460 --> 00:01:01,120
Here, light can still penetrate the water which allows photosynthesis to occur.
13
00:01:01,600 --> 00:01:03,000
Phytoplankton,
14
00:01:03,000 --> 00:01:07,500
trillions and trillions of single-celled algae and bacteria make up the foundation
15
00:01:07,560 --> 00:01:14,080
of the ocean's ecosystem, and they're consumed by bigger plankton, who are consumed by other species.
16
00:01:15,360 --> 00:01:21,500
The seafloor at this depth is akin to the Amazon rainforest, and is often covered with coral reefs, algae,
17
00:01:21,500 --> 00:01:25,440
and other sea plants that are home to a plethora of sea animals.
18
00:01:26,280 --> 00:01:30,820
So far, we've focused most of our attention on this comparatively pleasant environment,
19
00:01:30,820 --> 00:01:34,920
where we fish, swim, pollute, and do science.
20
00:01:35,680 --> 00:01:37,920
So, let's dive deeper.
21
00:01:38,520 --> 00:01:43,860
Moving from familiar coastal waters into deeper, more remote waters, we eventually reach the edge
22
00:01:43,860 --> 00:01:47,960
of the continental shelf, where we're confronted with the continental slope,
23
00:01:47,960 --> 00:01:50,480
the long descent down to the deep sea.
24
00:01:51,280 --> 00:01:56,980
With every additional metre of water, light fades drastically, which means there are basically
25
00:01:56,980 --> 00:02:03,100
no more plants, and the seemingly steep continental slope begins to remind us of the surface of the Moon.
26
00:02:03,760 --> 00:02:07,740
Looking out we're faced by what seems to be endless open water.
27
00:02:08,360 --> 00:02:14,200
Let's leave the slope behind us, and enter what's known as the twilight zone, the portal to the deep sea.
28
00:02:14,460 --> 00:02:18,860
As we sink down further, the water pressure rises to deadly levels.
29
00:02:19,780 --> 00:02:24,100
The deepest scuba dive ever came in at 332 meters.
30
00:02:24,100 --> 00:02:28,780
At that depth, the pressure is like having 200 cars stacked on top of you.
31
00:02:29,660 --> 00:02:33,340
Yet we've only completed 3% of our journey.
32
00:02:33,740 --> 00:02:37,660
While this region seems pretty grim, many fish and other animals
33
00:02:37,660 --> 00:02:40,300
actually spend at least half their lives down here.
34
00:02:40,900 --> 00:02:44,000
During the day, it's a good place to rest and recover,
35
00:02:44,000 --> 00:02:47,700
hidden from predators in the vast dark waters.
36
00:02:47,700 --> 00:02:53,360
At night, they can travel more safely into shallower zones to feed in the food-rich surface waters.
37
00:02:54,360 --> 00:02:59,660
In this transition zone between twilight and darkness, light becomes a powerful tool.
38
00:03:01,100 --> 00:03:05,100
Over 90% of the species indigenous to this deep environment
39
00:03:05,100 --> 00:03:07,840
use bioluminescence chemicals to create light.
40
00:03:08,780 --> 00:03:12,200
They do so as camouflage against the very faint sunlight,
41
00:03:12,200 --> 00:03:14,400
to send signals to potential mates,
42
00:03:14,480 --> 00:03:16,760
or to confuse and scare attackers.
43
00:03:17,200 --> 00:03:19,500
Or, they use lights to hunt.
44
00:03:20,580 --> 00:03:23,680
Another tool for survival in the dark is teamwork.
45
00:03:24,260 --> 00:03:28,400
At around 700 metres, we encounter a colony of siphonophores.
46
00:03:28,920 --> 00:03:33,420
They can be up to 50 metres in length, but are only as wide as a broomstick.
47
00:03:34,300 --> 00:03:40,000
To attract prey, a colony creates a tragically beautiful bright blue or red light,
48
00:03:40,000 --> 00:03:46,960
and deploys a curtain of tentacles filled with toxic needles that kill anything that comes too close.
49
00:03:47,940 --> 00:03:53,900
But most species living down here have to rely on an unlikely resource: marine snow.
50
00:03:54,360 --> 00:03:58,940
White flaky stuff that constantly sinks from the surface to the bottom of the ocean.
51
00:03:59,700 --> 00:04:02,480
It consists of dead plant or animal parts,
52
00:04:02,480 --> 00:04:03,640
fecal matter,
53
00:04:03,640 --> 00:04:05,440
shells, sand, or dust.
54
00:04:06,480 --> 00:04:12,880
Even though this doesn't sound very tasty, without this crucial resource, life in the deep sea would starve.
55
00:04:13,900 --> 00:04:18,740
It's in this area that the most fascinating battles between two unlikely enemies could happen.
56
00:04:19,600 --> 00:04:23,620
Sperm whales hunt and attack giant squid the size of a house.
57
00:04:24,660 --> 00:04:28,700
While the squid fight back ferociously, they probably don't stand a chance,
58
00:04:28,700 --> 00:04:31,940
but they do leave permanent marks on their killer's skin.
59
00:04:32,860 --> 00:04:38,720
As we reach 1,000 meters, deeper than the tallest structure built by humans, we need to be careful.
60
00:04:39,260 --> 00:04:43,820
This is the midnight zone, a place of utter darkness.
61
00:04:44,720 --> 00:04:50,140
A barely explored wet wasteland consisting of nothing but endless black open water.
62
00:04:50,900 --> 00:04:55,820
At these depths, it's harder for a human to take a swim than to take a walk in space.
63
00:04:57,080 --> 00:05:03,240
Finding food down here is really hard, so life had to adapt, and become extremely energy efficient.
64
00:05:03,820 --> 00:05:08,600
Like the 30-centimetre-long vampire squid that floats through the water without motion,
65
00:05:08,600 --> 00:05:11,400
with long and slender catching arms extended.
66
00:05:12,220 --> 00:05:16,300
They're covered in tiny stiff hairs, which brush food from the water.
67
00:05:16,880 --> 00:05:20,700
This saves a lot of energy compared to actively catching food.
68
00:05:21,900 --> 00:05:27,720
For carnivorous fish, it's much harder to find food since living prey is quite rare down here.
69
00:05:29,100 --> 00:05:35,060
So the hunters have to get a perfect grip on their victim on first strike, otherwise it will escape into the dark.
70
00:05:35,900 --> 00:05:39,760
Many deep-sea predators have several sets of long and deadly teeth.
71
00:05:40,620 --> 00:05:46,260
Like the viperfish, which uses its long fangs to trap even large prey and swallow it whole.
72
00:05:47,040 --> 00:05:51,060
Or the frilled shark, with its impressive set of 300 teeth,
73
00:05:51,060 --> 00:05:54,440
which are curved backwards to hook their victims in their mouths.
74
00:05:55,380 --> 00:05:56,640
We sink further,
75
00:05:56,880 --> 00:06:01,600
below the 3,800 mark, as deep as the grave of the Titanic.
76
00:06:02,000 --> 00:06:04,900
We are now at abyssal depths.
77
00:06:05,500 --> 00:06:08,340
Here, life happens in slow motion.
78
00:06:09,100 --> 00:06:13,320
Preserving every last bit of energy is crucial for survival.
79
00:06:14,100 --> 00:06:19,840
Everything down here hovers motionless, or swims in a slow, elegant fashion.
80
00:06:20,900 --> 00:06:26,620
The only time the animals living in this zone move fast is when they have to escape danger.
81
00:06:27,500 --> 00:06:34,780
Like the Dumbo octopod paddling with its ear-like fins, or the grenadiers fish with its slow, eel-like tail beats.
82
00:06:35,820 --> 00:06:39,200
At 4,000 meters, we finally reach ground again:
83
00:06:39,200 --> 00:06:41,020
the abyssal plain.
84
00:06:41,020 --> 00:06:45,400
It's covered in grey mud and rocks dusted with the remains of marine snow,
85
00:06:45,400 --> 00:06:51,060
which is consumed by animals like sea cucumbers, shrimp, sea urchins, and sea worms.
86
00:06:51,820 --> 00:06:56,060
In some regions of the seafloor, small, dark mineral deposits can be seen.
87
00:06:56,960 --> 00:06:59,160
These are manganese nodules.
88
00:07:00,000 --> 00:07:04,360
Deep-sea corals and sponges use them to anchor themselves on the bottom of the sea.
89
00:07:05,480 --> 00:07:10,420
Though life is sparse on the deep sea floor, even down here there are oases.
90
00:07:10,820 --> 00:07:17,560
In the rift valleys, where tectonic plates are splitting apart, magma heats up seawater and creates dark jets
91
00:07:17,560 --> 00:07:23,360
of water and minerals as hot as 400℃ that form elaborate chimneys and towers.
92
00:07:24,460 --> 00:07:31,060
Extremophile bacteria use the minerals to create organic substances that are the bases for unique ecosystems.
93
00:07:32,020 --> 00:07:37,500
As we descend further, we reach the deepest point of the abyssal plain at 6,000 meters.
94
00:07:38,540 --> 00:07:44,720
For most of the seafloor, this is as deep as it gets, but if we want to get to the deepest point of the oceans,
95
00:07:44,720 --> 00:07:46,640
we're actually only halfway there.
96
00:07:47,700 --> 00:07:51,400
Let's enter the hadal zone, the underworld of the sea.
97
00:07:52,340 --> 00:07:59,420
It consists of long narrow trenches that only make up around 0.25% of the oceans, and are among
98
00:07:59,420 --> 00:08:01,420
the most extreme environments on Earth.
99
00:08:02,180 --> 00:08:09,360
Only extremophiles exist down here, like the ethereal snailfish, that holds the record for the deepest living fish
100
00:08:09,360 --> 00:08:11,800
ever seen, at around 8,000 meters.
101
00:08:12,880 --> 00:08:17,720
We see spiky and sharp black rocks rush by as we sink down to more than 10,000.
102
00:08:18,780 --> 00:08:26,040
Until we reach the final slope, a trench inside the larger Mariana Trench with gently-sloping sides
103
00:08:26,040 --> 00:08:29,440
that enframe a valley about 1.6 kilometers wide.
104
00:08:30,460 --> 00:08:31,400
This is it.
105
00:08:31,400 --> 00:08:34,200
The deepest point, the Challenger Deep.
106
00:08:34,960 --> 00:08:37,300
11,000 meters below the surface.
107
00:08:38,680 --> 00:08:42,300
The water pressure here is 1,086 bar.
108
00:08:43,900 --> 00:08:48,120
Taking a swim here is like having to balance 1,800 elephants on top of you.
109
00:08:49,020 --> 00:08:51,920
But even here, life has found a way to thrive.
110
00:08:53,000 --> 00:08:57,880
Next to sea cucumbers, white and light pink amphipods wiggle their way through the water.
111
00:08:58,680 --> 00:09:00,420
Their size is astounding.
112
00:09:01,200 --> 00:09:05,600
While their shallow-water cousins are merely a few centimetres long, the deep-sea version
113
00:09:05,600 --> 00:09:07,620
can reach up to 30 centimeters.
114
00:09:08,980 --> 00:09:12,620
And there are other things floating elegantly through the water.
115
00:09:13,500 --> 00:09:16,840
Plastic bags that were found by scientists in 2018.
116
00:09:17,720 --> 00:09:21,940
Even the remotest place on Earth is not safe from human influence.
117
00:09:23,500 --> 00:09:29,220
There's nothing left to do now and our oxygen is running out, so we begin our ascent.
118
00:09:29,220 --> 00:09:39,140
[♪ Deep Sea Ambience ♪]
119
00:09:39,140 --> 00:09:44,696
After hours of traveling through dark nothingness, we finally see a glimpse of light.
120
00:09:44,900 --> 00:09:46,820
We arrive back at a calm surface.
121
00:09:48,080 --> 00:09:52,880
The oceans are so deep. There is so much of them.
122
00:09:53,660 --> 00:09:58,580
We owe it to ourselves and to our descendants to preserve them as well as we can.
123
00:09:59,640 --> 00:10:03,720
There are still so many wondrous things left to be discovered.
124
00:10:07,960 --> 00:10:11,280
So, you're all tingly now and want to go exploring.
125
00:10:11,980 --> 00:10:16,500
Why not start off with some juicy science? You can use our friends from Brilliant
126
00:10:16,500 --> 00:10:19,040
as your springboard for a knowledge deep dive.
127
00:10:19,940 --> 00:10:24,840
Brilliant is a website that helps you approach science in a practical way through interactive courses
128
00:10:24,840 --> 00:10:28,740
and daily problems in maths, science, and computer science.
129
00:10:29,060 --> 00:10:32,020
Instead of simply flooding you with information,
130
00:10:32,020 --> 00:10:34,860
you get the tools you need to untangle complex topics by yourself.
131
00:10:35,560 --> 00:10:38,440
It's hands-on learning, instead of chalk and talk.
132
00:10:38,820 --> 00:10:44,900
Plunge in and get to the bottom of courses about things like geometry, waves and light, gravitational physics
133
00:10:44,900 --> 00:10:45,940
and many more.
134
00:10:46,300 --> 00:10:50,800
Click the link in the description, or visit brilliant.org/nutshell to sign up for free
135
00:10:50,800 --> 00:10:53,640
and learn more things than there are fish in the sea.
136
00:10:54,080 --> 00:10:56,800
And there's an extra perk for Kurzgesagt viewers.
137
00:10:56,800 --> 00:10:59,800
The first 688 people to use the link
138
00:10:59,820 --> 00:11:04,540
get 20% off their annual membership, which lets you view all the daily problems in the archives
139
00:11:04,540 --> 00:11:06,200
and unlock every course.
140
00:11:06,900 --> 00:11:11,900
Brilliant helps you end your day a little smarter. Go ahead and take the plunge.
141
00:11:12,480 --> 00:11:17,940
Do you need more Vitamin Sea? We've also made an epic poster featuring some of the most fascinating creatures
142
00:11:17,940 --> 00:11:19,460
we encountered on our dive.
143
00:11:20,180 --> 00:11:24,460
It's much less work than an aquarium, but just as soothing and pretty.
144
00:11:25,220 --> 00:11:34,100
[♫ Outro Tune ♫]
14313
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.