At roughly the same time that ancient Egyptians were constructing their first great pyramids and Mesopotamians were building monumental temples and ziggurats, the Harappans of South Asia—also known as the Indus Valley Civilization—were erecting massive baked brick housing complexes and cutting elaborate canal systems. The civilization’s abrupt downfall remains one of the great mysteries of the ancient world. Now, for the first time, scientists have analyzed the genome of an ancient Harappan. The findings reveal little about why the society collapsed, but they illuminate both its past and its continuing genetic legacy in modern Indians.
“The Indus Valley Civilization has been an enigma for a long time,” says Priya Moorjani, a population geneticist at the University of California, Berkeley, who wasn’t involved with the study. “So it’s very exciting to … learn about [its] ancestry and history.”
The Indus Valley Civilization emerged sometime around 3000 B.C.E. and had collapsed by about 1700 B.C.E. During its height, it stretched across much of what is today northwestern India and parts of eastern Pakistan. It is alternatively known as the Harappan civilization, after the first of its sites to be excavated in Punjab province in Pakistan beginning in the 1820s. Along with ancient Egypt and Mesopotamia, it was among the world’s first large-scale urban agricultural societies, boasting somewhere between 1 million and 5 million inhabitants across five central cities.