homologous chromosomes that accounted for the considerable recombination of traits during sperm or egg production. Morgan received the Nobel Prize in 1934 for his work. He moved to CalTech in 1928 and established it as a world class center for genetic research. Morgan made substantial contributions to embryology before he switched to genetics. He studied the regeneration of limbs and the production of twins and chimeras by experimental means. His switch to genetics came from his association with
E. B. Wilson and his visit to
Hugo DeVries in Holland who claimed he observed new species arising in fields of primroses (
Oenothera lamarckiana). In addition to Muller, Morgan’s PhD and postdoctoral students included
Fernandus Payne, A. H. Sturtevant, C. B. Bridges, C. C. Tan, Jack Schultz, George Beadle, and
Otto Mohr.
7Muller’s Mentor Lineage to Morgan Via H. Newell Martin
Note: Morgan had two mentors at Johns Hopkins, Henry Newell Martin and William Keith Brooks. The intellectual lineage of Martin leads to Charles Darwin and Isaac Newton. The intellectual lineage from Brooks leads to Galileo and the fifteenth century. After the discussion of Morgan to Darwin through Martin, we will shift to Brooks’ intellectual lineage which goes back to 1499. Thus, there are two branches that fed into Morgan at Johns Hopkins University.
H. Newell Martin (1848–1896) was born in Newry, Ireland, and died in London, England. His father was a Congregational minister. He was educated at University College in London and assisted Thomas Henry Huxley. He studied physiology with Michael Foster and made it his life’s work. He was especially interested in the effects of temperature and exercise on heart beats. Cardiac physiology was Foster’s specialty. In 1876 he was hired by President Daniel Coit Gilman for the new university named for Johns Hopkins on recommendation from William Keith Brooks. At Johns Hopkins he introduced students to experimental methods and Thomas Hunt Morgan viewed his approach as more satisfactory than that of Brooks, who was his sponsor. Morgan found Brooks too philosophical in approach. Morgan, however, felt that the problems that Brooks championed, a search for experimental ways to study heredity and variation, were of far greater significance than those worked on by Martin. Martin married the widow of a Confederate General. He returned to England, however, because his wife died in 1892 and his health was impaired from alcoholism. He died young at 48.
Michael Foster (1836–1907) was born in Huntingdon, England. His father was a physician. Foster attended University College, London, where he studied with Thomas Henry Huxley. He became a physiologist and his two most famous students were H. Newell Martin and Charles Scott Sherrington. Sherrington won the Nobel Prize in 1932 for his work demonstrating synaptic communication among neurons in the brain and in muscle cells.
Thomas Henry Huxley (1825–1895) was born in Ealing, England, and died in Eastbourne, England. His father was a mathematics teacher and when the school failed, young Huxley had to drop out of his father’s school at the age of 10. He became an autodidact and taught himself Latin, Greek, and German and read widely. He served as an apprentice to surgeons and joined the Navy as an assistant surgeon. He was sent on the HMS Rattlesnake to an expedition to New Guinea and Australia. From his dredging at sea he collected numerous medusae and classified them. His surgical skills were exceptional, and he found these organisms had only two layers instead of three (they lacked mesoderm). His papers on what he called the Hydrozoa (today called Cnidarians) earned him election to the Royal Society at the age of 26. Huxley became friends with Charles Darwin and while he was initially skeptical of evolution and natural selection (which Darwin confided to him), he was won over by the evidence and became a strong supporter when Darwin’s theory came out. Huxley taught at the London School of Mines and there he developed a theory of liberal arts education which was influential in Europe and North America. His essay “A liberal education and how to get it” was published in 1868. His essay “On a piece of chalk” is one of the most captivating public lectures ever given on the significance of evolution. Huxley rejected formal religious belief and coined the term agnostic to represent his views that if a belief lacks scientific demonstration it can neither be proven nor disproven. His major students were Henry Newell Martin and Michael Foster.
Charles Darwin (1809–1882) was born in Shrewsbury, England, to a wealthy family. He died at his home, in Downe, England. His father was a physician and his mother was from the Wedgwood family of the pottery industry. His grandfather, Erasmus Darwin, was a member of the Lunar Society that brought the Enlightenment to England. Charles Darwin was sent to Edinburgh to learn medicine but did not like it. He transferred to Cambridge to study for the ministry and there enjoyed geology with Adam Sedgwick and botany with John Stevens Henslow. Henslow recommended Charles Darwin for the position of ship’s naturalist for the voyage of the HMS Beagle (1831–1836). Darwin’s account of the round the world trip established him as an appealing writer and a scientist of first rank. His letters to Henslow while on the trip were published and thus Darwin found himself well known to scientists on his return. Darwin developed a theory of evolution. First, he amassed evidence that evolution occurred using the fossils he found and his analysis of the distribution of life in the places he explored. Second, he proposed a theory of natural selection in which life is modified each generation by the survival or loss of competing individuals within and among species. He did not publish his theory until 1858. In 1859 a summary of some 300 pages was published as the Origin of species. It made Darwin one of the most controversial scientists of all time. It also transformed the life sciences. Darwin did not teach at universities. He used his inherited wealth to become a full-time scholar and he wrote at his home near London. He contributed to the careers of Joseph Hooker and Thomas Henry Huxley. He was influenced by the writings of Thomas Malthus and Charles Lyell. Malthus’s essay on population gave him the idea of natural selection. Lyell’s geology suggested a relatively similar climate and geological processes occurring over long periods of time, a theory called uniformitarianism.
Adam Sedgwick (1785–1873) was a British geologist. He was born in Dent, England, and died in Cambridge, England. He was educated at Cambridge and taught geology there. He identified the Devonian era as one that followed Cambrian rock formation and believed there was a series of floods followed by new creations by God. In 1831 he invited Darwin to do a geological study of Scottish rock formations when Darwin was a student at Cambridge. Although they remained friends, Sedgwick vehemently rejected Darwin’s evidence of evolution and its mechanism of natural selection.
Thomas Jones (1756–1807) was a mathematician and gifted teacher. He taught at Cambridge. He mentored Adam Sedgwick.
Thomas Postlethwaite (1731–1798) was a mathematician at Cambridge who mentored Thomas Jones. Postlethwaite was mentored by Stephen Whisson.
Stephen Whisson (1710–1783) was a mathematician at Cambridge who taught mathematics for physicists. He mentored Thomas Postlethwaite. He was mentored by Walter Taylor.
Walter Taylor (1700–1743) (no photo available) taught mathematics and Greek. He taught Stephen Whisson.
