They provide a rich resource for anything that eats them, and their diversity alone suggests that their predators might exhibit similar variety. And so it is. Many mammals, including members of almost all orders, sometimes feed on insects. Members of one order, the Insectivora, feed almost entirely on invertebrates, especially insects. Most rely more on their senses of hearing, smell, and touch than on vision.
Some shrews can echolocate.
The part of the brain that houses the sense of smell is especially well developed. The ear region of insectivores lacks an ossified bulla. The tympanic membrane is attached to a bony tympanic ring , and the middle ear may be partially enclosed by processes from adjacent bones. The jugal is reduced or may be absent, and the zygomatic arch is sometimes incomplete. The cheek teeth of many are dilambdodont , and even those with more derived molariform teeth tend to have cusps that can easily be identified according to the tribosphenic pattern.