Muslim physicians contributed to the field of medicine, including the subjects of anatomy and physiology: such as in the 15th century Persian work by Mansur ibn Muhammad ibn al-Faqih Ilyas entitled Tashrih al-badan (Anatomy of the body) which contained comprehensive diagrams of the body's structural, nervous and circulatory systems; or in the work of the Egyptian physician Ibn al-Nafis, who proposed the theory of pulmonary circulation. Avicenna's The Canon of Medicine remained an authoritative medical textbook in Europe until the 18th century. Abu al-Qasim al-Zahrawi (also known as Abulcasis) contributed to the discipline of medical surgery with his Kitab al-Tasrif ("Book of Concessions"), a medical encyclopedia which was later translated to Latin and used in European and Muslim medical schools for centuries. Other medical advancements came in the fields of pharmacology and pharmacy.
Try to answer this question if possible (otherwise reply "unanswerable"): Who first established the fields of anatomy and phusiology?
unanswerable