ARICA, CHILE—Bernardo Arriaza of the University of Tarapacá thinks that the Chinchorro people may have developed the practice of artificial mummification as a response to grief brought about by high infant mortality rates, according to a Phys.org report. The Chinchorro lived along the coast of Chile’s Atacama Desert and mummified their dead between 7000 and 3500 B.C. The earliest mummified individuals, many of whom were children, have been found…