New echolocator: Echolocation is a well demonstrated convergent sensory mode in bats and toothed whales. These lineages are not closely related, and this sense might be more broadly distributed than we recognize. Using a suite of approaches, He et al. show that the lineage of soft-furred tree mice (genus Typhlomys ) includes multiple echolocators. Clear evidence of the behavioral use of echolocation under fully dark conditions was supported by the convergence of ear bone morphology and hearing-related genes with other echolocating mammals. Science , aay1513, this issue p. eaay1513