The statues' physical traits also underwent reforms. Buddhas made in Yungang's early phase have a broad forehead, high, sharply-cut noses and elongated eyes and eyebrows. The look produces a feeling of solemnity, delivering a message of power, boldness and confidence from Northern Wei, a dynasty founded by nomadic Xianbei people in northern China.
Buddhist statues from the later stages look slim, gentle and elegant. This aesthetic conformed with a gesture prompted by the dynasty's new emperors, to take on Han conventions and achieve ethnic unity.
Noted architect Liang Sicheng and his team investigated Yungang Grottoes in 1933. In an article about this survey, he concluded that the introduction of Buddhist art brought no fundamental changes to the basic structures of Chinese architecture, but inspired the creation of sculptural styles.
He said: "The spirit, the soul and the taste (of Yungang) are essentially Chinese. Meanwhile, it produced a great deal of novel motifs, patterns and methods of sculpting that spread and have been preserved until today, which is a phenomenon worthy of recognition."