With a population exceeding 160 million in an area the size of Iowa, Bangladesh is Earth's most crowded nation. It also straddles several tectonic plate boundaries. This Bulletin follows geologists as they map a significant fault near the capital, Dhaka, and study how an earthquake on that fault could cause a river to shift dramatically through the populous region. Science Bulletins is a production of the National Center for Science Literacy, Education, and Technology (NCSLET), part of the Department of Education at the American Museum of Natural History. RELATED LINKS BanglaPIRE www.banglapire.org/ Ms. Ferguson in the Field msfergusoninthefield.blogspot.com/