Herbert McLean Evans (September 23, 1882 – March 6, 1971) was an American anatomist and embryologist best known for co-discovering Vitamin E.[1][2][3][4] He was born in Modesto, California.

His medical research at Berkeley addressed problems relating to human nutrition, endocrinology, embryology, and histology.

In 1922 along with Katharine Scott Bishop, during feeding experiments on rats, he co-discovered Vitamin E which is needed for human reproduction.

[8][9] Evans was also instrumental in developing reproductive systems research with Miriam Elizabeth Simpson and Choh Hao Li, by studying the oestrus cycle of rats.

Evans took a strong interest in the history of science and was an active collector of rare books in the field.