Description:
A camel's hump doesn't contain water or bone¡¦ it¡¯s fat. And each hump can
store up to 36 kilograms of it that can sustain the camel for weeks or even
months without food. The fat is incredibly nutritious and people are even starting
to use it in cooking for its health benefits. But the camel didn't actually get its hump
in the desert. In fact, Camels originated in the Canadian Arctic millions of years ago.
And they used their fatty humps to survive long winters.
Transcription:
Did you know that camels used to live in the Arctic tundra? Yes, camels!
Walking around on ice and snow. It's true. In 2013, scientists announced
they'd discovered mummified leg bones on Ellesmere Island, which belonged
to the ancestors of modern-day one- and two-humped camels. In fact,
enduring the frigid tundra is how scientists think camels got their iconic hump
in the first place, because what's inside helped them survive in an age when
many other animals were wiped out.
John Hare: What's inside a camel's hump
is fat, and a lot of people think it's water. But it's certainly not; it's fat, and it
nourishes them when they're on long journeys.
Narrator: That's right, fat.Each hump can store up to 36 kilograms of it,
which can sustain the camel for weeks or even months without food.
And that sort of adaptation was especially important 3.5 million years ago,
during the middle of an ice age, when the ancestors to modern camels were
hanging out in the Arctic tundra.
Hare: Talking about the Ice Age, when a lot of mammals were killed during
that time, and yet the camel managed to survive by developing this emergency
food system, if you like: the hump.
Narrator: Eventually, camels migrated across the Bering Strait into regions of
Asia and Africa, where the fat inside their humps helped them adapt yet again.
This time, to the blistering-hot temperatures of deserts like the Gobi and Sahara.
You see, camels are one of the only animals in the world that store all their fat
in one spot. And that's useful for keeping cool in a hot climate because heat
can escape faster from the rest of their body, which helps them maintain
a lower body temperature.Compare that to other mammals, like humans,
who store fat all over, making it a lot harder to stay cool. Today, camels still
use the fat in their humps as a food reserve, but they're not the only ones.
In extreme circumstances, the Turkana tribe in Kenya, for example, will eat
camel fat to survive.
Hare: They suffer a lot from periods of extreme drought, and I have seen
these people, they've been very, very short on food, and this is difficult to
believe, but it's true, slit open the top of a camel's hump, take out the fat
for their own consumption, and then put the top of the hump back on again.
Narrator: But don't worry, the camel makes a full recovery, and instances
are rare. But this practice has started to generate some buzz around camel fat
as a new superfood. Turns out, camel fat is loaded with fatty acids, vitamins,
and minerals. Desert Farms, a company that sells camel fat, says that just 1
tablespoon contains 40% of your daily vitamin B12 needs and three times the
amount of oleic acid than coconut oil, a superfood staple. And since all that
nutritious fat is what fills the hump out, when a camel fasts for long periods,
its hump can actually go limp.
Hare: The humps gradually diminish in size.
If it's been in a very harsh environment, they go completely limp and flop over
the side of the camel's backbone.
Narrator: Now, since we know that fat is what makes up the hump instead of
water, that got us
wondering: How do camels stay hydrated in such dry climates?
Well, they have unique blood cells that run throughout their entire body,
including a few in the hump itself.These blood cells are extremely elastic,
perfect for holding a lot of water.Camels can drink up to 115 liters in about
10 minutes, expanding the cells up to 240% in the process.
Hare: There are capillaries throughout its body,and when it has a drink,
it drinks and drinks and drinks, and it swells up, and it looks as though
it's pregnant.
Narrator: If that's not impressive enough, the wild camel of
China has even been known to survive on salt water.
So,whether it's surviving
the harsh desert heat, weeks without food and water,or even the Canadian
Arctic, the camel is one of the best adapters in the animal kingdom,
and that's in large part thanks to its iconic hump.
Questions:
1. Where do camels live? Where did they use to live?
2. What's inside a camel's hump?
3. Explain how do camels stay hydrated.