In what era did the development of polyphony begin to emerge

Polyphony is defined as the style of simultaneously combining a number of parts, each forming an individual melody and harmonizing with each other.

The development of polyphony began to emerge in the Romanesque era. The earliest type of polyphony was organum or the earliest harmonization of the chant.

answer; ///i believe that the correct answer is ; hieroglyphs or glyphs; the maya script, also known as maya glyphs, was the writing system of the maya civilization of mesoamerica; as always plz check first..good luck