Thomas Hunt Morgan: biography of this researcher

This researcher performed experiments that demonstrated the fulfillment of Mendel's laws.

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

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

Biography of Thomas Hunt Morgan

We will now take an in-depth look at the life of Thomas Hunt Morgan, his relationship with various American institutions, and his position with respect to the mainstream evolutionary ideas of the late 19th and early 20th centuries.

Early years and formation

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 Kentucky. There he focused primarily on science, especially natural history. During his vacation time in the summer, he went to work for the U.S. Geological Survey.

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

After two years working and publishing several publications, Morgan was chosen to receive a master's degree in science at the State College of Kentucky in 1888. This same institution offered Morgan work as a professor, although he ultimately chose to remain at John Hopkins.

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

Professional career and research

In 1890 Thomas H. Morgan was hired as a professor in charge of morphology courses at Bryn Mawr College, a sister institution of John Hopkins University.an institution twinned with John Hopkins University.

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

Stay in Europe

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

While in Naples he had contact with German researchers, who taught him the ideas of the school of Entwicklungsmechanik or developmental mechanics. This school was reactionary to the ideas of naturphilosophie, which until then had been the reference 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 of the embryos was formed by the mosaic theory.which held that the hereditary material was divided among the embryonic cells, which were predestined to become specific parts of the organism once it was mature.

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

When Morgan returned to Bryn Mawr in 1895 he was hired as a full-time professor. There he addressed such aspects of his research as larval development and regeneration. It was also at this time that he wrote his first book The Development of the Frog's Egg (1897).

At the turn of the 20th century, Morgan began research on sex determination, at a time when Nettie Stevens, another great researcher, had discovered the impact of the Y chromosomeAt that time, Nettie Stevens, another great researcher, had discovered the impact of the Y chromosome in the determination of male sex in humans.

Columbia University

In 1904, Morgan was invited by E. B. Wilson to join Columbia University, where he could work full time as a researcher.where he could carry out his research work full time. A year earlier he had written Evolution and Adaptationin which he explained that, like other biologists of the time, he had found evidence for the Biological evolution of species, but not in favor of the Darwinian mechanism of natural selection. However, years later, after the rediscoveries of Gregor Mendel's findings, Morgan changed his position.

Although at first he was skeptical about the Mendelian laws, given that they were being given enough importance as a theory to explain Charles Darwin's postulates, Morgan understood that they had enough sense and evidence behind them.

Studies with the fruit fly

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

He started crossing 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 heritable. 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 congeners. When the white-eyed flies mated with the red-eyed flies, their progeny had red eyes. However, when the second generation, i.e., the daughter flies, were crossed with each other, white-eyed flies emerged.

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

On the basis of this research, Morgan published in 1915, together with other prestigious scientists of the time, the book The Mechanism of Mendelian The Mechanism of Mendelian Hereditywhich is considered the fundamental book for understanding genetics. After the insect studies, 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 advocated racist ideas.

Final 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). There he did research on embryology, biophysics, biochemistry, genetics, evolution and physiology.. He worked at CALTECH until 1942, when he retired and became professor emeritus. However, even in retirement, he would continue his research in sexual differentiation, regeneration and embryology.

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

Evolutionary position

Morgan was interested in evolution throughout 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 with respect to Darwinian and Lamarckian evolutionary ideas.

In his book Evolution and Adaptation (1903) he was critical of Charles Darwin's postulates. According to Morgan, selection could never produce a completely new species only by acting on merely perceptible differences between individuals..... He also rejected the idea of acquired characters postulated by Neolamarckism.

It must be said that Morgan was not a scientist going 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, caused some of Darwin's original ideas to fall into disarray.

However, after his studies with Drosophila melanogaster, Morgan changed his position. Mutations are important for evolutionThe mutations are important for evolution, since 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 during his lifetime, the most notable being the following:
• Ph.D. degree from the University of Kentucky.
• Elected member of the National Academy of Sciences (1909).
• Elected member of the British Royal Society (1919).
• Received the Darwin Medal (1924).
• Received the Nobel Prize in medicine and physiology (1933).

In addition, several institutions have been founded in his name, such as the Thomas Hunt Morgan School of Biological Sciences at the University of Kentucky. Also, the American Genetics Society annually awards the Thomas Hunt morgan medal to members of the institution who have contributed to the field.

Bibliographical references:

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