Read the passage below and answer the question that follows.
The Sahara is the largest hot desert in the world, covering over 3.6 million square miles of Northern Africa.
Its vast landscape is not entirely sand; it also includes rocky plateaus, gravel plains, and salt flats.
Despite its arid conditions, the Sahara is home to a surprising variety of life.
Adapted animals like the Fennec fox, with its large ears to dissipate heat, and the Addax antelope, which can get water from the plants it eats, thrive in this harsh environment.
Plants such as the date palm and various grasses have also developed unique survival mechanisms, like long roots to reach deep water sources.
What is the main idea of this passage?
