Read the quote.
"... the eastern Andes on one side... and the maritime cordillera on the other. Between them there
is an extensive and very lofty plateau, 13,000 to 14,000 feet above the sea, with the lake called
Titicaca... The surrounding mountains form a region of frost and snow.
The hardy llamas and
alpacas live and breed amidst the tufts of coarse grass.... Besides the grass, there is a lowly
shrub called tola, which can be used as firewood. Quinua belonging to the spinach family, can alone
be raised at the higher elevations, yielding a small grain which, by itself, is insufficient to maintain human life."