Herbert McLean Evans was born on September 23, 1882 in Modesto, California, the son, grandson and nephew of prominent physicians. In 1904 he received a B.S. degree from the University of California, Berkeley. After spending one year at the University of California School of Medicine, he completed his medical education at Johns Hopkins, where he studied with such distinguished individuals as Franklin P. Mall and William Stewart Halsted. Evans published papers as a student (including major contributions to Mall and Keibel's Manual of Human Embryology) and over a period of sixty-two years he authored, or co-authored, over six hundred papers. Following his graduation in 1908, Dr. Evans joined the staff of Dr. Mall's department.

In 1915 he was appointed chairman of the Department of Anatomy at the University of California. Here he embarked on experimental studies that gained for him and his associates worldwide recognition. In 1921 he and Joseph A. Long described the estrous cycle of the female rat, which eventually led to an interest in the influence of vitamins on fecundity and the discovery in 1926 of vitamin E. Also in collaboration with Dr. Long, he confirmed the pituitary gland's role in growth. In 1930 he was appointed Director of the Institute of Experimental Biology on the Berkeley campus. In 1939 he and co-workers separated the growth hormone from the total secretion of the anterior pituitary; in 1944 he and Drs. Cho Hao Li and M. E. Simpson crystallized a pure form. Later, with Drs. Li and Simpson, he separated and purified the pituitary's interstitial-cell-stimulating hormone. Following his retirement in 1952, Dr. Evans taught the histology course for medical students on the Berkeley campus.

Dr. Evans received numerous international honors, including horary doctoral degrees from leading educational institutions in Europe, South American and the United States. A Fellow of the American Academy of Arts and Sciences, Dr. Evans was also a member of the National Academy of Sciences, the Kaiserliche Leopoldinisch-Carolinische Deutche Akademie der Naturforscher, Societas Regia Medicorum Budapestinensis, American Physiological Society and the Society for Experimental Biology and Medicine. He was also past president of the American Association of Anatomists and an honorary member of many foreign medical and scientific societies. Dr. Evans was one of the founders of the History of Science Society, and as a lifelong bibliophile he amassed what was described in 1961 as "one of the world's great collections of scientific first editions." Dr. Evans died on March 5, 1971.