Which mammal is the smallest?

   Roosting deep in the limestone caves along the Kwae Noi River in western Thailand is the Kitti's hog-nosed bat (Craseonycteris thonglongyai), the world's smallest mammal. It is approximately 1 inch long—about the size of a bumblebee, hence its nickname bumblebee bat—and weighs .07 ounce. It was first discovered and described in 1974, and it is classified as rare by the World Conservation Union; the population of Kitti's hog-nosed bat is estimated at approximately 200. The United States Department of the Interior classifies the mammal as endangered. The ears are relatively large, the eyes are small, and the nose resembles that of a pig. This tailless, flying mammal lives in bamboo forests and teak plantations, flying at dusk to dine on insects and spiders.