GANSU, CHINA—China Daily reports that six groups of rock art etchings estimated to be 3,500 years old were discovered at high altitude on northwest China’s Qilian Mountain. Most of the images depict deer, cattle, and hunting scenes. One of the deer images shows an animal with antlers and bent legs. A young animal appears to be nursing at its abdomen. Du Chengfeng of the Chinese Rock Art Institution said the images were chiseled with metal tools, which helped archaeologists to date them to the Bronze Age or early Iron Age. The artwork also offers clues to the ancient environment. “Different types of deer have a preferred living environment and are highly dependent on changing vegetation,” Du said. “Most of them live in tundra, forest areas, deserts, shrubs, and swamps.” For a look at petroglyhs made by the Comanche, go to "Rock Art of the Comanche Warriors."