Rodent poop gauges ancient rains

Size of chinchilla pellets reveals past desert environment

IGUASSU FALLS, Brazil — The size of fecal pellets in ancient rodent middens can provide clues about the abundance of rainfall in times past, new analyses suggest.

Middens are, in essence, rodent latrines shared by a family or social group. Abandoned middens are composed of large numbers of fecal pellets cemented together by crystallized urine, reported Claudio Latorre Hidalgo, a paleoecologist at Pontificia Universidad Católica de Chile in Santiago, on August 9 at the Meeting of the Americas.