In the 1790s, the Italian priest and biologist Lazzaro Spallanzani realized that bats could still navigate in spaces too dark for a captive owl. In a series of cruel experiments, he showed that bats could orient when blinded, but would blunder into objects when deafened or gagged. He never fully grasped the meaning of these curious findings and could only write that “the ear of the bat serves more efficiently for seeing, or at least for measuring distances, than do its eyes.”
