If one throws a rock into the wetlands around Icirrus city, they will find the rippling it creates echoed in countless larger and larger waves around the moor. These waves are not a phenomenon based solely in physics, as many Icirrus science teachers have struggled to convince their students; the thrown rock was mistaken for communication by the local Palpitoad, and they have answered in kind.
Although they are capable of speech, and far more easily heard by other species than the Tympole, Palpitoad eschew ordinary sound for communication by immense waves through land and water. To these pokemon, if one is worthy of being heard, their voice must not merely move through air, but also move the water, or on land the earth. Much as humans have tried to make their music and television louder and louder to compete with other broadcasters, Palpitoad have raced against each other for eons, seeking to create the greatest waves they can, so that all others of their species will pay them heed.
This is a minimal issue in the swamp water the Palpitoad call home, for it can not be navigated by ships and other pokemon have learned to tolerate them. But some trainers bring their beloved Tympole long distances before evolution, and many travelers are intrigued by the prospect of catching Palpitoad. Those who do so must be careful, for if they do not learn to keep their voice down when near civilization, Palpitoad have been known to sink ships and topple houses with the force of their vibrations. Most trainers let their Palpitoad out only in the wilderness and in pokemon arenas built to withstand the shocks of a great many species, for the property damage these creatures can cause would bankrupt even a Gym Leader!