A modern physical theatre has grown from a variety of origins. Mime and theatrical clowning schools, such as L'École Internationale de Théâtre Jacques Lecoq in Paris, have had a big influence on many modern expressions of physical theatre. Practitioners such as Steven Berkoff and John Wright received their initial training at such institutions. Contemporary dance has also had a strong influence on what we regard as physical theatre, partly because most physical theatre requires actors to have a certain level of physical control and flexibility. These qualities are rarely found in those who do not have some sort of movement background. Modern physical theatre also has strong roots in more ancient traditions such as "Commedia dell'arte", and some suggest links to the ancient greek theatre, particularly the theatre of Aristophanes.