Not sure about that; I'd guess that vibration-sensing organs first evolved to sense disturbances (in water, on seafloor, later on dry ground and in air) caused by movement, whether of a predator, prey, or a potential mate. Intentional vocalizations for signalling purposes then evolved to utilize the existing modality.
Not sure about that; I'd guess that vibration-sensing organs first evolved to sense disturbances (in water, on seafloor, later on dry ground and in air) caused by movement, whether of a predator, prey, or a potential mate. Intentional vocalizations for signalling purposes then evolved to utilize the existing modality.
Ears arose long before speech did. They evolved in response to changes in the environment, e.g., the existence of speech.