Researchers say that two rivers merged some 89,000 years ago and gave the mightiest peak in the Himalayas a huge growth spurt. Researchers say that two rivers merged some 89,000 years ago and gave the mightiest peak in the Himalayas a huge growth spurt. Mount Everest, Himalayas, Geology, Rivers, Mountains, Research, Nature Geoscience (Journal), your-feed-science NYT > Science