Thomas Hunt Morgan: biography of this researcher

Thomas Hunt Morgan was a great man of science, whose research has been considered the cornerstone essential for understanding genetics as we understand it today, along with Gregor Mendel.

This American was an evolutionary biologist, embryologist, geneticist and author of several papers who had the honor of receiving a Nobel Prize for his active scientific career. Let's take a deeper look at his story through this short biography of Thomas Hunt Morgan.

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Biography of Thomas Hunt Morgan

Next we will see in depth the life of Thomas Hunt Morgan, his relationship with various institutions Americans and their position regarding the main evolutionary ideas of the late 19th century and beginning of the XX.

Early years and training

Thomas Hunt Morgan was born on September 25, 1866 in Lexington, Kentucky. At the age of sixteen he attended the State College of Kentucky, now the University of that state. In that center he focused above all on science, especially natural history. During his vacation time, in the summer, he dedicated himself to working for the United States Geological Survey.

He graduated in 1886 with a Bachelor of Science degree. the following summer he attended the Marine Biology School in Annisquam, Massachusetts, where he would become interested in zoology at John Hopkins University..

After two years working and publishing various publications, Morgan was chosen to receive a master of science from the State College of Kentucky in 1888. This same institution offered Morgan a job as a professor, although he ultimately chose to continue at John Hopkins.

It was at this time that he finished his thesis on the embryology of sea spiders (pycnogonida), to determine its phylogenetic relationship with other arthropods. Based on his embryonic development, he established that they were more related to terrestrial spiders than to crustaceans. His publication was awarded a doctorate in 1890. With the money he earned as a prize for the publication of the thesis, Morgan took the opportunity to travel through the Caribbean and Europe to continue his research in zoology.

Professional career and research

In 1890 Thomas H. Morgan he was hired as a professor in charge of courses on morphology at the Bryn Mawr school, a sister institution with John Hopkins University.

His working life at the institution was very intense. He gave lectures five days a week, twice a day, mainly oriented to biology in general terms. However, despite being a good teacher, he wanted to focus on research.

stay in Europe

In 1894 he traveled to Naples to carry out research in the laboratories of the Stazione Zoologica in the city. There he completed a study on the embryology of ctenophores, an almost microscopic life form.

Being in Naples he had contact with German researchers, who taught him the ideas of the Entwicklungsmechanik school or developmental mechanics. This school was reactionary to the ideas of naturphilosophie, which until then had been the benchmark in the science of morphology during the 19th century.

At that time there was a great debate about how embryos were formed. One of the most popular explanations was the mosaic theory., which held that the hereditary material was divided between the embryonic cells, which were predestined to become specific parts of the organism once it was mature.

Others, being the case of Morgan at that time, thought that the development was due to epigenetic factors, where the interactions between the protoplasm and the nucleus of embryonic cells affected the way in which they were they developed.

When Morgan returned to Bryn Mawr in 1895 he was taken on as a full-time teacher. There he addressed in his research aspects such as the development of larvae and their regeneration. It was also then that he wrote his first book. The Development of the Frog's Egg (1897).

At the beginning of the 20th century, Morgan began research on sex determination, by which time Nettie Stevens, another great researcher, had discovered the impact of the Y chromosome on determining the male sex in humans.

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columbia university

In 1904, Morgan he was invited by E. b. Wilson to join Columbia University, where he could carry out his investigative work full time. A year earlier he had written Evolution and Adaptation, where he explained that, like other biologists of the time, he had found evidence of the biological evolution of the species, but not being in favor of the mechanism of natural selection darwinian. However, years later, after the rediscoveries of the findings made by Gregor Mendel, Morgan would change his position.

Although he was initially skeptical of Mendelian laws, since he was being given enough importance as a theory to explain the postulates of Charles Darwin, Morgan realized that they made a lot of sense and evidence behind.

Studies with the fruit fly

In 1908 Morgan he started working with the fruit fly (Drosophila melanogaster). He mutated, through the use of chemicals, physics and radiation, specimens of this common fly.

He began to cross the specimens to find mutations that were heritable, but at first he did not achieve significant results. In addition, he had some trouble detecting which mutations were actually hereditary. Subsequently, when he detected the mutations, he saw that they followed the laws proposed by Mendel.

Morgan found a male fly with white eyes that stood out among its red-eyed conspecifics. When the white-eyed flies mixed with the red ones, their progeny had red eyes. However, when the second generation, that is, the daughter flies, was crossed between them, white-eyed flies arose.

Based on his research with flies, he published an article in 1911 in which he explained that some traits were inherited. in a sex-linked way, plus it was likely that the particular trait was stored on one of the chromosomes sexual.

Based on these investigations, Morgan published in 1915, together with other prestigious scientists of the time, the book The Mechanism of Mendelian Heredity, which is considered the fundamental book to understand genetics. After the studies with the insect, Morgan returned to the field of embryology, in addition to addressing the heritability of genes in other species.

In 1915 he was critical of a new movement that had emerged from science, eugenics, especially when it defended racist ideas.

Last years

Several years later, in 1928, Thomas Hunt Morgan moved to California to take charge of the biology section of the California Institute of Technology (CALTECH). Over there he researched on embryology, biophysics, biochemistry, genetics, evolution and physiology. He would work at CALTECH until 1942, when he would retire and become a professor emeritus. However, even in retirement, he would continue to investigate sexual differentiation, regeneration and embryology.

Finally, Thomas Hunt Morgan would die on December 4, 1945 at the age of 79 after suffering a heart attack.

evolutionary stance

Morgan was interested in evolution all his life.. Already as a young man he wrote his famous thesis on the phylogeny of sea spiders, in addition to writing up to four books in which he explained his position on Darwinian evolutionary ideas and lamarckistas.

in his book Evolution and Adaptation (1903) he is critical of the postulates of Charles Darwin. According to Morgan, selection could never produce an entirely new species solely by acting on merely perceptible differences between individuals.. He also rejected the idea of ​​acquired characters postulated by Neo-Lamarckism.

It must be said that Morgan was not a scientist who went against the grain. In fact, the years between 1875 and 1925 are known as 'the eclipse of Darwinism', since the scientific advances of the time, together with changes in positions within the natural sciences, made some of Darwin's original ideas waters.

However, after studying him with Drosophila melanogaster, Morgan changed his position. Mutations are important for evolution, given that it is those characters that are inherited that significantly affect the anatomical and behavioral changes of the species. These characters are inherited following, many times, the laws proposed by Mendel.

Honors

Among the distinctions that Thomas Hunt Morgan obtained, we find the following:

• Thomas Hunt Morgan received several honors in life, the most notable being the following:
• Ph.D. from the University of Kentucky.
• Elected to the National Academy of Sciences (1909).
• Elected member of the British Royal Society (1919).
• He received the Darwin medal (1924).
• He received the Nobel Prize in Medicine and Physiology (1933).

In addition, several institutions have been founded named after him, such as the Thomas Hunt Morgan School of Biological Sciences at the University of Kentucky. Also, the American Genetic Society awards the Thomas Hunt Morgan Medal annually to members of the institution who have contributed to the field.

Bibliographic references:

• Allen, G. AND. (1978). Thomas Hunt Morgan: The Man and His Science. Princeton University Press.
• Allen, G. AND. (2000). "Morgan, Thomas Hunt". American National Biography. Oxford University Press.
• Kohler, R. AND. (1994). Lords of the Fly: Drosophila Genetics and the Experimental Life. University of Chicago Press.