Kidney Structure in Neotropical Bats

Abstract

Renal indices involving the relative thickness of the medulla and inner medulla were determined for Neotropical representatives of all New World bat families. Renal morphology in bats is primarily a function of diet and secondarily related to environmental dehydration pressure. Bats that are primarily frugivorous or nectarivorous possess kidneys with relatively thin and undivided medullae; those species with other feeding preferences possess kidneys with relatively thick medullae, which are subdivided into inner and outer zones. Renal indices are similar between insectivorous bats inhabiting mesic and wet habitats but are lower than ones inhabiting arid regions. The statistical relationship between renal index and body weight is enigmatic in bats, but all species have renal indices that differ according to food habits.