Asanga, the founder of Yogachara Buddhism, was a renowned philosopher and teacher who lived in India during the 4th century CE. He is known for his significant contributions to the development and evolution of Buddhist philosophy, particularly in the Yogachara school.

At the beginning of his career, Asanga followed the traditional Theravada teachings and practices of Buddhism. However, he soon became dissatisfied with the limitations of this school and sought to explore new perspectives and approaches to understanding the nature of reality.

Asanga's teachings began to evolve as he delved deeper into the study of Buddhist scriptures and engaged in intense meditation practices. He became a disciple of the Mahayana master Maitreya, who is said to have appeared to Asanga in a vision and imparted the teachings of the Yogachara school.

Under the guidance of Maitreya, Asanga developed a deep understanding of the concept of shunyata or emptiness, which is a fundamental principle in Yogachara philosophy. He also studied the teachings of the Yogachara masters Vasubandhu and Dignaga, who had laid the foundations of this school.

Asanga's teachings continued to evolve as he incorporated his own insights and interpretations into the Yogachara philosophy. He emphasized the importance of the mind in understanding reality and believed that all phenomena are ultimately created by the mind.

One of Asanga's most significant contributions to the evolution of Yogachara teachings is the concept of the three natures – parikalpita, paratantra, and parinishpanna. These three natures explain the nature of reality and the relationship between the mind and the external world.

Asanga's teachings also evolved in response to the criticisms and debates from other Buddhist schools, such as the Madhyamaka and the Abhidharma. He engaged in lively debates and discussions with these schools, which helped refine and strengthen his teachings.

Asanga's teachings also had a significant impact on the development of Buddhism in other countries, particularly in China and Tibet. His works, such as the Mahayanasamgraha and the Abhidharmasamuccaya, were translated into Chinese and Tibetan, and his ideas influenced the development of Mahayana Buddhism in these regions.

In conclusion, Asanga's teachings evolved significantly over time as he deepened his understanding of Buddhist philosophy and incorporated new insights and perspectives. His contributions to the development of Yogachara philosophy continue to be studied and revered by Buddhist practitioners and scholars around the world.