Page 197 - Super Earth Encyclopedia

DROUGHT

SURVIVORS

DESERT

Regions that get very little rain become deserts.
Their clear skies allow the Sun to shine all day, so most
deserts are very hot, although they cool down at night.
This is a harsh environment for plant life, so the driest
deserts are virtually barren. But others get some rain,
and plants have evolved ways of making the most of it.
Thorny shrubs have long roots for soaking it up and
small leaves to reduce water loss. The cacti of American
deserts have fleshy stems that store water, and other
plants have fleshy roots for the same job. Some plants
survive for years as seeds; they sprout, flower, and
produce seeds only if they are soaked by a rare rainstorm.

AROUND THE WORLD

Most deserts lie in the world’s
subtropics, where high-level NORTH
air moving away from the AMERICA EUROPE ASIA
equator sinks and stops the
formation of clouds. Cold
central Asian deserts are cut Equator AFRICA
off from rain-bearing oceanic
SOUTH
air by high mountain ranges AMERICA AUSTRALASIA
such as the Himalayas.

NIGHT HUNTER

Insects, lizards, and small
burrowing mammals such as
mice are often common in
deserts. Most of them hide
underground by day, and
emerge to feed at night. They
provide prey for hunters like
this American elf owl, which LIVING EARTH
often nests in holes bored in
big cacti by woodpeckers.

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