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In Chapter 5, you have seen that water means life to
plants, animals and people. It is difficult for anyone to
live in places where there is no water to drink, where
there is no grass for their cattle to feed on and where
there is no water to help the crops to grow.
We will now learn about the places in the world where
people have learned to cope with extreme harsh
temperatures; in some places as hot as fire and some as
cold as ice. These are the desert areas of the world. These
are characterised by low rainfall, scanty vegetation and
extreme temperatures. Depending on the temperatures
there can be hot deserts or cold deserts. The people
inhabit these lands wherever little water is available to
practise agriculture.
THE HOT DESERT – SAHARA
Look at the map of the world and the
continent of Africa. Locate the Sahara
desert covering a large part of North
Africa. It is the world’s largest desert. It
has an area of around 8.54 million
sq. km. Do you recall that India has an
area of 3.28 million sq. km? The Sahara
desert touches eleven countries. These
are Algeria, Chad, Egypt, Libya, Mali,
Mauritania, Morocco, Niger, Sudan,
Tunisia and Western Sahara.
When you think of a desert the picture
that immediately comes to your mind is that of sand. But
besides the vast stretches of sands, that Sahara desert is
covered with, there are also gravel plains and elevated
plateaus with bare rocky surface. These rocky surfaces
may be more than 2500m high at some places.
Fig. 7.1: The Sahara Desert
Glossary
Desert: It is an arid
region characteriesed
by extremely high or
low temperatures and
has scarce vegetation.
Reprint 2024-25
Page 2


In Chapter 5, you have seen that water means life to
plants, animals and people. It is difficult for anyone to
live in places where there is no water to drink, where
there is no grass for their cattle to feed on and where
there is no water to help the crops to grow.
We will now learn about the places in the world where
people have learned to cope with extreme harsh
temperatures; in some places as hot as fire and some as
cold as ice. These are the desert areas of the world. These
are characterised by low rainfall, scanty vegetation and
extreme temperatures. Depending on the temperatures
there can be hot deserts or cold deserts. The people
inhabit these lands wherever little water is available to
practise agriculture.
THE HOT DESERT – SAHARA
Look at the map of the world and the
continent of Africa. Locate the Sahara
desert covering a large part of North
Africa. It is the world’s largest desert. It
has an area of around 8.54 million
sq. km. Do you recall that India has an
area of 3.28 million sq. km? The Sahara
desert touches eleven countries. These
are Algeria, Chad, Egypt, Libya, Mali,
Mauritania, Morocco, Niger, Sudan,
Tunisia and Western Sahara.
When you think of a desert the picture
that immediately comes to your mind is that of sand. But
besides the vast stretches of sands, that Sahara desert is
covered with, there are also gravel plains and elevated
plateaus with bare rocky surface. These rocky surfaces
may be more than 2500m high at some places.
Fig. 7.1: The Sahara Desert
Glossary
Desert: It is an arid
region characteriesed
by extremely high or
low temperatures and
has scarce vegetation.
Reprint 2024-25
50 OUR ENVIRONMENT
Do you know?
Fig. 7.2: Sahara in Africa
Al Azizia in the Sahara
desert, south of Tripoli,
Libya recorded the
highest temperature of
57.7°C in 1922.
Climate
The climate of the Sahara desert is scorching hot and
parch dry. It has a short rainy season. The sky is
cloudless and clear. Here, the moisture evaporates
faster than it accumulates. Days are unbelievably hot.
The temperatures during the day may soar as high as
50°C, heating up the sand and the bare rocks, which
in turn radiates heat making everything around hot.
The nights may be freezing cold with temperatures
nearing zero degrees.
Flora and Fauna
Vegetation in the Sahara desert includes cactus, date
palms and acacia. In some places there are oasis – green
islands with date palms surrounding them. Camels,
hyenas, jackals, foxes, scorpions, many varieties of
Do you know?
You will be surprised
to know that present
day Sahara once used
to be a lush green
plain. Cave paintings
in Sahara desert show
that there used to be
rivers with crocodiles.
Elephants, lions,
giraffes, ostriches,
sheep, cattle and
goats were common
animals. But the
change in climate has
changed it to a very
hot and dry region.
Reprint 2024-25
Page 3


In Chapter 5, you have seen that water means life to
plants, animals and people. It is difficult for anyone to
live in places where there is no water to drink, where
there is no grass for their cattle to feed on and where
there is no water to help the crops to grow.
We will now learn about the places in the world where
people have learned to cope with extreme harsh
temperatures; in some places as hot as fire and some as
cold as ice. These are the desert areas of the world. These
are characterised by low rainfall, scanty vegetation and
extreme temperatures. Depending on the temperatures
there can be hot deserts or cold deserts. The people
inhabit these lands wherever little water is available to
practise agriculture.
THE HOT DESERT – SAHARA
Look at the map of the world and the
continent of Africa. Locate the Sahara
desert covering a large part of North
Africa. It is the world’s largest desert. It
has an area of around 8.54 million
sq. km. Do you recall that India has an
area of 3.28 million sq. km? The Sahara
desert touches eleven countries. These
are Algeria, Chad, Egypt, Libya, Mali,
Mauritania, Morocco, Niger, Sudan,
Tunisia and Western Sahara.
When you think of a desert the picture
that immediately comes to your mind is that of sand. But
besides the vast stretches of sands, that Sahara desert is
covered with, there are also gravel plains and elevated
plateaus with bare rocky surface. These rocky surfaces
may be more than 2500m high at some places.
Fig. 7.1: The Sahara Desert
Glossary
Desert: It is an arid
region characteriesed
by extremely high or
low temperatures and
has scarce vegetation.
Reprint 2024-25
50 OUR ENVIRONMENT
Do you know?
Fig. 7.2: Sahara in Africa
Al Azizia in the Sahara
desert, south of Tripoli,
Libya recorded the
highest temperature of
57.7°C in 1922.
Climate
The climate of the Sahara desert is scorching hot and
parch dry. It has a short rainy season. The sky is
cloudless and clear. Here, the moisture evaporates
faster than it accumulates. Days are unbelievably hot.
The temperatures during the day may soar as high as
50°C, heating up the sand and the bare rocks, which
in turn radiates heat making everything around hot.
The nights may be freezing cold with temperatures
nearing zero degrees.
Flora and Fauna
Vegetation in the Sahara desert includes cactus, date
palms and acacia. In some places there are oasis – green
islands with date palms surrounding them. Camels,
hyenas, jackals, foxes, scorpions, many varieties of
Do you know?
You will be surprised
to know that present
day Sahara once used
to be a lush green
plain. Cave paintings
in Sahara desert show
that there used to be
rivers with crocodiles.
Elephants, lions,
giraffes, ostriches,
sheep, cattle and
goats were common
animals. But the
change in climate has
changed it to a very
hot and dry region.
Reprint 2024-25
LIFE IN THE DESERTS 51
Do you know?
Depressions are formed
when the wind blows
away the sands. In the
depressions where
underground water
reaches the surface,
an oasis is formed.
These areas are fertile.
People may settle
around these water
bodies and grow date
palms and other
crops. Sometimes the
oasis may be
abnormally large.
Tafilalet Oasis in
Morocco is a large
oasis with an area of
about 13,000 sq.km.
Fig. 7.3: Oasis in the Sahara Desert
People
The Sahara desert despite its harsh climate has been
inhabited by various groups of people, who pursue
different activities. Among them are the Bedouins and
Tuaregs. These groups are nomadic tribes rearing
livestock such as goats, sheep, camels and horses.
These animals provide them with milk, hides from
which they make leather for belts, slippers, water
bottles; hair is used for mats, carpets, clothes and
blankets. They wear heavy robes as protection against
dust storms and hot winds.
The oasis in the Sahara and the Nile Valley in Egypt
supports settled population. Since water is available, the
people grow date palms. Crops such as rice, wheat, barley
and beans are also grown. Egyptian cotton, famous
worldwide is grown in Egypt.
The discovery of oil – a product in great demand
throughout the world, in Algeria, Libya and Egypt is
constantly transforming the Sahara desert. Other
minerals of importance that are found in the area include
iron, phosphorus, manganese and uranium.
The cultural landscape of the Sahara is undergoing
change. Gleaming glass cased office buildings tower over
mosques and superhighways crisscross the ancient camel
paths. Trucks are replacing camels in the salt trade.
Tuaregs are seen acting as guides to foreign tourists.
More and more nomadic herdsmen are taking to city life
finding jobs in oil and gas operations.
snakes and lizards are the prominent animal species
living there.
Do you know?
Scientists have
actually found
skeletons of fish in
this desert. What
could have happened?
Reprint 2024-25
Page 4


In Chapter 5, you have seen that water means life to
plants, animals and people. It is difficult for anyone to
live in places where there is no water to drink, where
there is no grass for their cattle to feed on and where
there is no water to help the crops to grow.
We will now learn about the places in the world where
people have learned to cope with extreme harsh
temperatures; in some places as hot as fire and some as
cold as ice. These are the desert areas of the world. These
are characterised by low rainfall, scanty vegetation and
extreme temperatures. Depending on the temperatures
there can be hot deserts or cold deserts. The people
inhabit these lands wherever little water is available to
practise agriculture.
THE HOT DESERT – SAHARA
Look at the map of the world and the
continent of Africa. Locate the Sahara
desert covering a large part of North
Africa. It is the world’s largest desert. It
has an area of around 8.54 million
sq. km. Do you recall that India has an
area of 3.28 million sq. km? The Sahara
desert touches eleven countries. These
are Algeria, Chad, Egypt, Libya, Mali,
Mauritania, Morocco, Niger, Sudan,
Tunisia and Western Sahara.
When you think of a desert the picture
that immediately comes to your mind is that of sand. But
besides the vast stretches of sands, that Sahara desert is
covered with, there are also gravel plains and elevated
plateaus with bare rocky surface. These rocky surfaces
may be more than 2500m high at some places.
Fig. 7.1: The Sahara Desert
Glossary
Desert: It is an arid
region characteriesed
by extremely high or
low temperatures and
has scarce vegetation.
Reprint 2024-25
50 OUR ENVIRONMENT
Do you know?
Fig. 7.2: Sahara in Africa
Al Azizia in the Sahara
desert, south of Tripoli,
Libya recorded the
highest temperature of
57.7°C in 1922.
Climate
The climate of the Sahara desert is scorching hot and
parch dry. It has a short rainy season. The sky is
cloudless and clear. Here, the moisture evaporates
faster than it accumulates. Days are unbelievably hot.
The temperatures during the day may soar as high as
50°C, heating up the sand and the bare rocks, which
in turn radiates heat making everything around hot.
The nights may be freezing cold with temperatures
nearing zero degrees.
Flora and Fauna
Vegetation in the Sahara desert includes cactus, date
palms and acacia. In some places there are oasis – green
islands with date palms surrounding them. Camels,
hyenas, jackals, foxes, scorpions, many varieties of
Do you know?
You will be surprised
to know that present
day Sahara once used
to be a lush green
plain. Cave paintings
in Sahara desert show
that there used to be
rivers with crocodiles.
Elephants, lions,
giraffes, ostriches,
sheep, cattle and
goats were common
animals. But the
change in climate has
changed it to a very
hot and dry region.
Reprint 2024-25
LIFE IN THE DESERTS 51
Do you know?
Depressions are formed
when the wind blows
away the sands. In the
depressions where
underground water
reaches the surface,
an oasis is formed.
These areas are fertile.
People may settle
around these water
bodies and grow date
palms and other
crops. Sometimes the
oasis may be
abnormally large.
Tafilalet Oasis in
Morocco is a large
oasis with an area of
about 13,000 sq.km.
Fig. 7.3: Oasis in the Sahara Desert
People
The Sahara desert despite its harsh climate has been
inhabited by various groups of people, who pursue
different activities. Among them are the Bedouins and
Tuaregs. These groups are nomadic tribes rearing
livestock such as goats, sheep, camels and horses.
These animals provide them with milk, hides from
which they make leather for belts, slippers, water
bottles; hair is used for mats, carpets, clothes and
blankets. They wear heavy robes as protection against
dust storms and hot winds.
The oasis in the Sahara and the Nile Valley in Egypt
supports settled population. Since water is available, the
people grow date palms. Crops such as rice, wheat, barley
and beans are also grown. Egyptian cotton, famous
worldwide is grown in Egypt.
The discovery of oil – a product in great demand
throughout the world, in Algeria, Libya and Egypt is
constantly transforming the Sahara desert. Other
minerals of importance that are found in the area include
iron, phosphorus, manganese and uranium.
The cultural landscape of the Sahara is undergoing
change. Gleaming glass cased office buildings tower over
mosques and superhighways crisscross the ancient camel
paths. Trucks are replacing camels in the salt trade.
Tuaregs are seen acting as guides to foreign tourists.
More and more nomadic herdsmen are taking to city life
finding jobs in oil and gas operations.
snakes and lizards are the prominent animal species
living there.
Do you know?
Scientists have
actually found
skeletons of fish in
this desert. What
could have happened?
Reprint 2024-25
52 OUR ENVIRONMENT
THE COLD DESERT - LADAKH
Ladakh is a cold desert lying in the Great Himalayas,
on the eastern side of Jammu and Kashmir (Fig. 7.4).
The Karakoram Range in the north and the Zanskar
mountains in the south enclose it. Several rivers flow
through Ladakh, Indus being the most important
among them. The rivers form deep valleys and gorges.
Several glaciers are found in Ladakh, for example the
Gangri glacier.
The altitude in Ladakh varies from about 3000m
in Kargil to more than 8,000m in the Karakoram.
Due to its high altitude, the climate is extremely cold
and dry. The air at this altitude is so thin that the
heat of the sun can be felt intensely. The day
temperatures in summer are just above zero degree
and the night temperatures well below –30°C. It is
freezing cold in the winters when the temperatures may
remain below –40°C for most of the time. As it lies
Word Origin
Ladakh is made up of
two words – “La”
meaning ‘mountain
pass’ and “Dak”
meaning ‘country’
Do you know?
Drass, one of the
coldest inhabited
places on earth is
located in Ladakh.
Fig. 7.4: Ladakh
Reprint 2024-25
Page 5


In Chapter 5, you have seen that water means life to
plants, animals and people. It is difficult for anyone to
live in places where there is no water to drink, where
there is no grass for their cattle to feed on and where
there is no water to help the crops to grow.
We will now learn about the places in the world where
people have learned to cope with extreme harsh
temperatures; in some places as hot as fire and some as
cold as ice. These are the desert areas of the world. These
are characterised by low rainfall, scanty vegetation and
extreme temperatures. Depending on the temperatures
there can be hot deserts or cold deserts. The people
inhabit these lands wherever little water is available to
practise agriculture.
THE HOT DESERT – SAHARA
Look at the map of the world and the
continent of Africa. Locate the Sahara
desert covering a large part of North
Africa. It is the world’s largest desert. It
has an area of around 8.54 million
sq. km. Do you recall that India has an
area of 3.28 million sq. km? The Sahara
desert touches eleven countries. These
are Algeria, Chad, Egypt, Libya, Mali,
Mauritania, Morocco, Niger, Sudan,
Tunisia and Western Sahara.
When you think of a desert the picture
that immediately comes to your mind is that of sand. But
besides the vast stretches of sands, that Sahara desert is
covered with, there are also gravel plains and elevated
plateaus with bare rocky surface. These rocky surfaces
may be more than 2500m high at some places.
Fig. 7.1: The Sahara Desert
Glossary
Desert: It is an arid
region characteriesed
by extremely high or
low temperatures and
has scarce vegetation.
Reprint 2024-25
50 OUR ENVIRONMENT
Do you know?
Fig. 7.2: Sahara in Africa
Al Azizia in the Sahara
desert, south of Tripoli,
Libya recorded the
highest temperature of
57.7°C in 1922.
Climate
The climate of the Sahara desert is scorching hot and
parch dry. It has a short rainy season. The sky is
cloudless and clear. Here, the moisture evaporates
faster than it accumulates. Days are unbelievably hot.
The temperatures during the day may soar as high as
50°C, heating up the sand and the bare rocks, which
in turn radiates heat making everything around hot.
The nights may be freezing cold with temperatures
nearing zero degrees.
Flora and Fauna
Vegetation in the Sahara desert includes cactus, date
palms and acacia. In some places there are oasis – green
islands with date palms surrounding them. Camels,
hyenas, jackals, foxes, scorpions, many varieties of
Do you know?
You will be surprised
to know that present
day Sahara once used
to be a lush green
plain. Cave paintings
in Sahara desert show
that there used to be
rivers with crocodiles.
Elephants, lions,
giraffes, ostriches,
sheep, cattle and
goats were common
animals. But the
change in climate has
changed it to a very
hot and dry region.
Reprint 2024-25
LIFE IN THE DESERTS 51
Do you know?
Depressions are formed
when the wind blows
away the sands. In the
depressions where
underground water
reaches the surface,
an oasis is formed.
These areas are fertile.
People may settle
around these water
bodies and grow date
palms and other
crops. Sometimes the
oasis may be
abnormally large.
Tafilalet Oasis in
Morocco is a large
oasis with an area of
about 13,000 sq.km.
Fig. 7.3: Oasis in the Sahara Desert
People
The Sahara desert despite its harsh climate has been
inhabited by various groups of people, who pursue
different activities. Among them are the Bedouins and
Tuaregs. These groups are nomadic tribes rearing
livestock such as goats, sheep, camels and horses.
These animals provide them with milk, hides from
which they make leather for belts, slippers, water
bottles; hair is used for mats, carpets, clothes and
blankets. They wear heavy robes as protection against
dust storms and hot winds.
The oasis in the Sahara and the Nile Valley in Egypt
supports settled population. Since water is available, the
people grow date palms. Crops such as rice, wheat, barley
and beans are also grown. Egyptian cotton, famous
worldwide is grown in Egypt.
The discovery of oil – a product in great demand
throughout the world, in Algeria, Libya and Egypt is
constantly transforming the Sahara desert. Other
minerals of importance that are found in the area include
iron, phosphorus, manganese and uranium.
The cultural landscape of the Sahara is undergoing
change. Gleaming glass cased office buildings tower over
mosques and superhighways crisscross the ancient camel
paths. Trucks are replacing camels in the salt trade.
Tuaregs are seen acting as guides to foreign tourists.
More and more nomadic herdsmen are taking to city life
finding jobs in oil and gas operations.
snakes and lizards are the prominent animal species
living there.
Do you know?
Scientists have
actually found
skeletons of fish in
this desert. What
could have happened?
Reprint 2024-25
52 OUR ENVIRONMENT
THE COLD DESERT - LADAKH
Ladakh is a cold desert lying in the Great Himalayas,
on the eastern side of Jammu and Kashmir (Fig. 7.4).
The Karakoram Range in the north and the Zanskar
mountains in the south enclose it. Several rivers flow
through Ladakh, Indus being the most important
among them. The rivers form deep valleys and gorges.
Several glaciers are found in Ladakh, for example the
Gangri glacier.
The altitude in Ladakh varies from about 3000m
in Kargil to more than 8,000m in the Karakoram.
Due to its high altitude, the climate is extremely cold
and dry. The air at this altitude is so thin that the
heat of the sun can be felt intensely. The day
temperatures in summer are just above zero degree
and the night temperatures well below –30°C. It is
freezing cold in the winters when the temperatures may
remain below –40°C for most of the time. As it lies
Word Origin
Ladakh is made up of
two words – “La”
meaning ‘mountain
pass’ and “Dak”
meaning ‘country’
Do you know?
Drass, one of the
coldest inhabited
places on earth is
located in Ladakh.
Fig. 7.4: Ladakh
Reprint 2024-25
LIFE IN THE DESERTS 53
in the rain shadow of the Himalayas, there is little
rainfall, as low as 10 cm every year. The area
experiences freezing winds and burning hot sunlight.
You will be surprised to know that if you sit in the
sun with your feet in the shade, you may suffer from
both sunstroke and frost bite at the same time.
Flora and Fauna
Due to high aridity, the vegetation is sparse. There are
scanty patches of grasses and shrubs for animals to
graze. Groves of willows and poplars are seen in the
valleys. During the summers, fruit trees such as apples,
apricots and walnuts bloom. Several species of birds are
sighted in Ladakh. Robins, redstarts, Tibetan snowcock,
raven and hoopoe are common. Some of these are
migratory birds. The animals of Ladakh are wild goats,
wild sheep, yak and special kinds of dogs. The animals
are reared to provide for the milk, meat and hides. Yak’s
milk is used to make cheese and butter. The hair of the
sheep and goat is used to make woollens.
People
Do you find any resemblance between the people of
Ladakh and the inhabitants of Tibet and Central Asia?
The people here are either Muslims or Buddhists. In
fact several Buddhists monasteries dot the Ladakhi
landscape with their traditional ‘gompas’. Some
famous monasteries are Hemis, Thiksey, Shey and
Lamayuru (Fig. 7.5).
In the summer season the people are busy cultivating
barley, potatoes, peas, beans and turnip. The climate in
winter months is so harsh that
people keep themselves engaged in
festivities and ceremonies. The
women are very hard working. They
work not only in the house and
fields, but also manage small
business and shops. Leh, the capital
of Ladakh is well connected both
by road and air. The National
Highway 1 connects Leh to Kashmir
Valley through the Zoji La Pass. Can
you name some more passes in
the Himalayas?
Do you know?
The finest cricket bats
are made from the
wood of the willow
trees.
Do you know?
The Chiru or the
Tibetan antelope is an
endangered species. It
is hunted for its wool
known as shahtoosh,
which is light in
weight and extremely
warm.
Fig. 7.5: Thiksey Monastery
Do you know?
Ladakh is also known
as Khapa-chan which
means snow land.
Reprint 2024-25
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FAQs on NCERT Textbook: Life in the Deserts - Social Studies (SST) Class 7

1. What are the characteristics of life in the deserts?
Ans. Life in the deserts is characterized by extreme temperatures, scarcity of water, and limited vegetation. Desert organisms have developed adaptations to survive in these harsh conditions, such as the ability to store water, nocturnal activity patterns, and specialized physiological features.
2. How do desert plants and animals adapt to survive in the desert?
Ans. Desert plants adapt to survive in the desert by having deep root systems to reach underground water sources, developing thick waxy coatings on their leaves to reduce water loss through evaporation, and their ability to remain dormant during long periods of drought. Desert animals, on the other hand, have evolved various strategies such as being nocturnal to avoid extreme heat, having specialized kidneys to conserve water, and possessing camouflage or protective coloration to blend in with their surroundings.
3. What are some examples of desert plants and animals?
Ans. Examples of desert plants include cacti, succulents, and tumbleweeds. These plants have adapted to store water in their stems, leaves, or roots. Examples of desert animals include camels, kangaroo rats, and scorpions. Camels have the ability to store water in their humps, kangaroo rats can survive without drinking any water, and scorpions have a protective exoskeleton and can survive in extreme temperatures.
4. How do desert ecosystems contribute to the environment?
Ans. Desert ecosystems play an important role in the environment. They help in preventing soil erosion by anchoring the soil with their roots and providing shade to the ground. Desert plants also act as carbon sinks, absorbing carbon dioxide from the atmosphere. Desert animals contribute to pollination and seed dispersal, helping in the reproduction of plants. Additionally, desert ecosystems are home to unique and diverse species, making them important for biodiversity conservation.
5. What are the challenges faced by human populations living in deserts?
Ans. Human populations living in deserts face several challenges. The scarcity of water is a major challenge, as access to freshwater sources is limited. Extreme temperatures and lack of vegetation also make it difficult to engage in agriculture or livestock rearing. Desert dwellers often face food scarcity and rely on trade or import for their sustenance. Additionally, desertification and climate change pose further threats to the livelihoods of people living in deserts.
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