Junxian Shen and his group found just before ovulation female concave-eared frogs emit calls that are distinct from males?advertisement calls, having higher fundamental frequencies and harmonics, and shorter call duration. The played-back female calls increased males?calling activity and approached the source of the noise. On hearing the female call, a male usually oriented his body and made a long-distance hop towards the loudspeaker with hyperacute phonotaxis precision (localization error of < 1o), rivaling that of vertebrates with the highest localization acuity (barn owl, dolphins, elephants and humans).