For example, the use of counterpoint and fugue, which is considered characteristic of the Baroque era (or period), was continued by Haydn, who is classified as typical of the Classical era. Beethoven, who is often described as a founder of the Romantic era, and Brahms, who is classified as Romantic, also used counterpoint and fugue, but the romantic and sometimes yearning qualities of their music define their era. The prefix "neo-" is used to describe a 19th-, 20th-, or 21st-century composition written in the style of an earlier era, such as Classical or Romantic. Stravinsky's "Pulcinella", for example, is a neoclassical composition because it is stylistically similar to works of the Baroque era. Burgh (2006), suggests that the roots of Western classical music ultimately lie in ancient Egyptian art music via cheironomy and the ancient Egyptian orchestra, which dates to 2695 BC. The development of individual tones and scales was made by ancient Greeks such as Aristoxenus and Pythagoras. Pythagoras created a tuning system and helped to codify musical notation. Ancient Greek instruments such as the aulos (a reed instrument) and the lyre (a stringed instrument similar to a small harp) eventually led to several modern-day instruments of a classical orchestra. The antecedent to the early period was the era of ancient music before the fall of the Roman Empire (476 AD). The Medieval era includes music from after the fall of Rome to about 1400. Monophonic chant, also called plainsong or Gregorian chant, was the dominant form until about 1100. Catholic monks developed the first forms of modern European musical notation in order to standardize liturgy throughout the worldwide Church. Polyphonic (multi-voiced) music developed from monophonic chant throughout the late Middle Ages and into the Renaissance, including the more complex voicings of motets. A number of European classical musical instruments have roots in Eastern instruments that were adopted from the medieval Islamic world. For example, the Arabic rebab is the ancestor of all European bowed string instruments, including the lira, rebec and violin. Many of the instruments used to perform medieval music still exist, but in different forms. Medieval instruments included the flute, the recorder and plucked string instruments like the lute. As well, early versions of the organ and fiddle (or vielle) existed. Medieval instruments in Europe had most commonly been used singly, often self accompanied with a drone note, or occasionally in parts.