How you survive the coldest place on Earth - Nadia Frontier

186,450 views ・ 2023-10-10

TED-Ed


Please double-click on the English subtitles below to play the video.

00:07
The vast, white ice surface of Antarctica
0
7253
2795
00:10
stretches for over 3 million square kilometers:
1
10048
2836
00:12
empty, desolate, and almost completely silent.
2
12884
2878
00:16
But appearances can be deceiving.
3
16637
1961
00:18
On the coast of this expanse,
4
18681
1710
00:20
just a few meters beneath the ice lies a multicolored constellation of life.
5
20391
4213
00:24
This remarkably diverse realm is home to over 8,000 species of sea denizens
6
24812
5172
00:29
who rely on an arsenal of otherworldly traits to survive.
7
29984
3796
00:34
So how do these species not only live, but thrive,
8
34113
2670
00:36
in conditions most animals would be unable to bear?
9
36783
2836
00:40
Antarctic waters are some of the most consistently frigid in the world,
10
40119
4004
00:44
hovering below 0 degrees Celsius for a large portion of the year.
11
44207
4004
00:48
This means burning energy too quickly can be deadly,
12
48377
3254
00:51
so survival in this ecosystem looks slow and steady.
13
51714
3420
00:55
Freezing temperatures persist even in the summer,
14
55551
2836
00:58
but this season brings a rare gift: sunlight.
15
58471
2878
01:01
For a brief period, it’s abundant,
16
61766
2127
01:03
shining through the ice for 24 hours a day.
17
63893
2628
01:06
This infusion of energy drives intense coastal phytoplankton blooms,
18
66687
4296
01:11
transforming the waters into a thick green soup.
19
71192
3045
01:14
Marine life both large and small takes advantage of this bounty,
20
74737
3837
01:18
including the giant Antarctic isopod.
21
78574
2503
01:21
Cousins of the humble pill bug,
22
81160
1877
01:23
these crustaceans can reach up to 11 centimeters long,
23
83079
3587
01:26
and they never miss the opportunity for a meal.
24
86791
2502
01:29
The scavengers eat a wide variety of prey, including other giant isopods.
25
89669
4421
01:34
And by slowing their metabolisms, they can make this food last,
26
94090
3420
01:37
with one study showing specimens surviving for 50 days without eating.
27
97552
4087
01:42
Since this adaptation involves careful conservation of energy,
28
102014
3671
01:45
giant isopods spend most of their time stationary or inching across the seafloor.
29
105685
5547
01:51
Meanwhile, their tiny amphipod relatives celebrate the summer
30
111607
3754
01:55
by releasing offspring alongside the algal explosion,
31
115361
3170
01:58
ensuring their young have an abundance of food.
32
118531
2294
02:01
And sea cucumbers carpeting the seafloor hoover up the dense plankton
33
121117
4629
02:05
with outstretched tentacles,
34
125788
1460
02:07
producing nutrient-rich feces that nourish nearby life.
35
127248
3253
02:10
But this big summer blowout doesn’t last long.
36
130751
2670
02:13
The first signs of autumn arrive in fine needles of frazil ice.
37
133462
4338
02:17
These slowly coagulating crystals form a skin across the surface,
38
137967
3921
02:22
then mix with falling snow before freezing into a thin crust of ice.
39
142096
4338
02:26
The waters get darker and colder.
40
146642
1961
02:28
And in this swiftly dimming world,
41
148603
1876
02:30
a set of long, spiky limbs sidle into view.
42
150479
2837
02:33
With up to six pairs of legs, these giant sea spiders aren’t arachnids,
43
153524
4213
02:37
but rather a related class of marine arthropod unique to the seafloor.
44
157820
4088
02:42
In addition to housing some of the animal’s organs,
45
162200
2711
02:44
its legs are covered in tiny holes,
46
164911
2168
02:47
which grow more numerous as the spider ages.
47
167079
2628
02:49
These holes will likely help absorb the dissolved oxygen
48
169832
2878
02:52
that saturates these freezing southern waters.
49
172710
2252
02:55
Since oxygen fuels growth,
50
175004
1835
02:56
many local species have evolved to take advantage of this abundance,
51
176839
3670
03:00
and it may be one of the reasons that gigantism is so common in this region.
52
180593
4046
03:05
Individual sea spiders, for instance, can grow to the size of dinner plates.
53
185181
4004
03:09
But soon, these underwater giants will be moving slower than ever.
54
189227
3920
03:13
As winter settles in, the sea floor becomes even colder.
55
193940
3420
03:17
Waters fall to negative 1.8 degrees Celsius.
56
197360
3420
03:21
On the surface, the thin icy crust thickens into a layer called nilas,
57
201030
4838
03:26
and young sea ice starts forming ridges that block out the sun.
58
206035
3712
03:29
The ocean begins to mirror the still landscape above it.
59
209914
2961
03:33
Antarctic sea cucumbers and urchins go into dormancy for months,
60
213626
4212
03:37
and their metabolic rates fall to the slowest on Earth.
61
217838
2962
03:40
Antarctic limpets continue feeding,
62
220800
2419
03:43
but at such a gradual pace that they're largely still surviving
63
223219
3045
03:46
on energy reserves from the summer.
64
226264
1793
03:48
Tiny crustaceans survive off the traces of algae
65
228557
3087
03:51
growing on their home’s icy ceiling,
66
231644
2085
03:53
raising their young in these expansive winter nurseries.
67
233729
2670
03:56
But this seemingly endless winter won't last forever.
68
236691
3253
04:00
As spring comes, light slowly begins to trickle back down through the ice.
69
240236
3962
04:04
And week by week, bit by bit,
70
244198
1919
04:06
this underwater world will begin waking up
71
246117
2544
04:08
to begin its delicate, slow-motion dance once again.
72
248661
3629
About this website

This site will introduce you to YouTube videos that are useful for learning English. You will see English lessons taught by top-notch teachers from around the world. Double-click on the English subtitles displayed on each video page to play the video from there. The subtitles scroll in sync with the video playback. If you have any comments or requests, please contact us using this contact form.

https://forms.gle/WvT1wiN1qDtmnspy7