Yaxchilan’s whistles

Eight clay whistles found buried in Small Acropolis temples (650–800 BC) of Yaxchilan were analyzed. The study was centered on three dual whistles with body shapes resembling those of frogs. A method developed in previous studies and evidence from several disciplines were applied. Experimental replicas were made to find possible ancient ways of construction and to test hypotheses. The Helmholtz equation for globular resonators was calculated, sound signals were analyzed with spectrograms, and radiated acoustic power in different modes was estimated (0.0005–0.003W). The power level indicates that whistles’ sounds could not be heard well if they were played along with louder Mayan aerophones like those of Bonampak’s mural band nor in noisy celebrations in big plazas. Clay frogs were adequate to be used in the Small Acropolis, in the Labyrinth and by big groups, surely related to religion. The whistles can sing like natural frogs and produce beats, and they might have been used to produce a chorus in ceremon...