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As recently as 6,000 B.C., much of the Sahara region was semiarid grassland where humans hunted wild oxen and antelope. A. There was enough freshwater for Saharan peoples to move freely throughout the region without having to manage the resources they hunted and gathered. B. When the drying climate forced cattle and humans close to each other in areas with water supplies, humans gained control over the cattle and eventually domesticated them. C. Once Saharans controlled the breeding of their cattle, the characteristics of the cattle changed rapidly, increasing their reproductive rates and milk production. D. Herders soon began selecting breeding animals to produce offspring with different horn shapes and hide colors, although the advantages of controlled inbreeding were not apparent to them at first. E. Although the Saharan peoples were remarkably sophisticated artists, they had only a few simple possessions, like adzes and the bows and arrows they used for hunting. F. As the drought worsened around 3500 B.C. and conditions for herders became more favorable to the south, the Saharan people moved into savanna regions, where they grew different crops.