Herbert McLean Evans (September 23, 1882 – March 6, 1971) was an American anatomist and
embryologist best known for co-discovering
Vitamin E.[2][3][4][5]
Evans became associate professor of anatomy at Johns Hopkins University. Evans moved back to California in 1915 and was made professor of anatomy at the
University of California, Berkeley, and held that position until his death.
His medical research at Berkeley addressed problems relating to human
nutrition,
endocrinology,
embryology, and
histology. In 1918, his research into the number of human
chromosomes led him to believe the number to be 48, when most people assumed the number to be much higher. It was only later discovered that the correct figure was 46. Evans had much greater success however with
hormones extracted from the anterior lobe of the
pituitary gland. He isolated
Human Growth Hormone, which is essential for human growth and development. In 1922 along with
Katharine Scott Bishop, during feeding experiments on rats, he co-discovered
Vitamin E which is needed for human reproduction.[6] Evans became director of the Institute of Experimental Biology at Berkeley in 1931. With
Gladys Anderson Emerson, he reported the isolation of the pure Vitamin E from wheat germ in 1937.[7][8] He also determined the formula C29H50O2.[9][10] 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 is also credited with developing
Evans blue, a method which determines
blood volume in humans and animals.
Evans took a strong interest in the history of science and was an active collector of rare books in the field. His collection was later acquired by the
Harry Ransom Center at the
University of Texas at Austin.
"No single feature of man's past equals in importance his attempt to understand the forces of Nature and himself."
Bibliography
Evans, H. McLean (1904) A New Cestraciont Spine from the Lower Triassic of Idaho. The University Press: Berkeley, California.
Evans, H. McLean and Scott, Katharine J. (1921) On the Differential Reaction to Vital Dyes Exhibited by the Two Groups of Connective-tissue Cells. Carnegie Institution of Washington.
Evans, H. McLean and Long, Joseph A. (1922) The oestrous cycle in the rat and its associated phenomena. Univ. of California Press: Berkeley, California.
Evans, H. McLean and Cole, Harold H. (1931) An Introduction to the Study of the Oestrous Cycle in the Dog. University of California Press: Berkeley, California.
Evans, H. McLean and Swezy, Olive (1931) Ovogenesis and the Normal Follicular Cycle in Adult Mammalia. University of California Press: Berkeley, California.
Evans, H. McLean and Becks, Hermann (1953) Atlas of the Skeletal Development of the Rat (Long-Evans strain): normal and hypophysectomized. American Institute of Dental Medicine: San Francisco.
Evans, H. McLean, ed. (1959) Men and Moments in the History of Science. University of Washington Press: Seattle.
ISBN0-8371-2458-1
^Evans, H. M.; Emerson, O. H.; Emerson, G. A. (2009). "THE ISOLATION FROM WHEAT GERM OIL OF AN ALCOHOL, α-TOCOPHEROL, HAVING THE PROPERTIES OF VITAMIN E". Nutrition Reviews. 32 (3): 80–82.
doi:
10.1111/j.1753-4887.1974.tb06280.x.
PMID4593257.