The document discusses adaptations needed to survive in the Sahara desert. The Sahara spans North Africa and has summer temperatures often above 90 degrees Fahrenheit, sometimes reaching over 100 degrees. To cope with these extreme heat conditions, the body's lymphatic system would need to adapt for excess water consumption. The endocrine system would release more hormones for metabolism and development. And the nervous system would adapt to the large temperature fluctuations between hot days and cold nights.