Lynn Margulis: Biography and Contributions

Lynn Margulis , whose maiden name was Lynn Petra Alexander, was a scientist born in the United States in 1938. Her branch of specialization was evolutionary biology and her contributions in that field made her one of the most recognized researchers of the moment.

Among the most important works of Margulis stand out the theory of serial endosymbiosis and the theory of symbiogenetics. His contributions were received at first with skepticism; He received numerous rejections before being able to publish the results of his investigations, considered unorthodox.

Biography of Lynn Margulis

Margulis also adhered to the so-called Gaia hypothesis, developed previously by atmospheric scientist, scientist and chemist James Lovelock. Likewise, Margulis put a lot of interest in bringing science to the public, doing a great job of dissemination.

She was a university professor in many institutions and her achievements were recognized with awards such as the National Medal of Science, granted by the American President Bill Clinton in 1999; and for appointments as a doctor honoris cause in universities around the world.


Lynn Margulis was born on March 5, 1938 in the American city of Chicago. His first studies were conducted in a public school in the city. Given the potential that it demonstrated, her parents decided to transfer her to the Laboratory School of the University of Chicago, a rather elitist private center.

Being so young, Margulis began to show the personality that always characterized her and decided to return to her public school, since she was not comfortable in the private school environment.

University studies

The future scientist stood out very soon for her academic results and for her sharp intelligence. With only 16 years old he entered the program for advanced students of the University of the city; four years later he graduated.

According to his own words, in those years he obtained"a title, a husband (Carl Sagan) and a more lasting critical skepticism".

Margulis continued her training at the University of Wisconsin. There, with only 20 years, he started working on a Master in General Genetics and Population Genetics. At the same time, she worked as an assistant teacher.

His experience during those formative years, coupled with his interest in bacteria, were the basis of some of his most revolutionary theories.

Professional life

Two years later, in 1960, he finished his master's degree in science by presenting a study on RNA in the Amoeba proteus . His next step was to start preparing for the doctorate, this time at the University of California. His doctoral thesis, presented in 1965, was titled A pattern of unusual thymidine incorporation in Euglena .

From that moment it was very common to find his name in prestigious scientific journals, despite the fact that, on many occasions, his works clashed with the hegemonic theories of the moment. For example, your research On the origin of the mitotic cell It was rejected fifteen times before it was published in 1967.

Margulis divorced her first husband, the astronomer, cosmologist and astrophysicist Carl Sagan, in 1965. Two years later she remarried Thomas Margulis, a crystallographer who took the surname.

His first book completed saw the light in 1970, edited by Yale University. As with his articles, this publication was not simple either: the first publisher to which he had submitted it rejected the project after analyzing it for five months.

Other works

Lynn acquired more and more prestige thanks to research such as that carried out on the contribution of microorganisms to evolution. This recognition led her to travel around the world to participate in conferences and congresses. For example, in 1975 he participated in the International Congress of Botany held in the Soviet Union.

His endosymbiotic theory, one of the most important among those presented, was forged in those years. In this theory he studied the evolutionary consequences of symbiosis.

However, the work of Margulis encompassed numerous fields. As a sample of this diversity of interests, we can point out his studies on the possibilities of life on other planets, or the publication in 1984 of an article on the evolution of sexual reproduction.

Between 1984 and 1987 the biologist worked in Mexico, looking for evidence on how the biosphere interacts and the different geological systems.

Last years and death

Margulis' career was awarded with multiple awards. She was invited to be part of the National Academy of Sciences of the United States, and also of the Russian Academy of Sciences. He also received the National Medal of Sciences of the United States in 1999.

Besides, she worked as a mentor at the University of Boston and received numerous doctorates honoris cause of universities around the world.

Margulis never stopped working. In fact, he died on November 22, 2011 while in his laboratory in Amherst, Massachusset. He was trying to find the only piece he lacked to complete his endosymbiotic theory when he suffered a stroke.


Theory of serial endosymbiosis

It is one of the most important contributions of Margulis to science. According to their studies, eukaryotic cells (those of animals, plants or fungi) come from the incorporation of prokaryotic cells (bacteria).

According to Margulis, these prokaryotes become part of the mitochondria, chloroplasts and other organelles.

The researcher was not able to completely close her theory, since the hypothesis of the incorporation of spirochetes is not considered proven. It was precisely what he was trying to show when he died.

Theory of symbiogenesis

It is the other great theory proposed by Margulis and was quite controversial when faced with some of the approaches established by the students of evolution.

The author affirmed that the complex organisms that appear as the final steps of the evolutionary system are composed of communities of less complex and surviving beings.

Specifically, his hypothesis pointed to bacteria as responsible for the ultimate complexity of organisms.

While multicellular organisms (animals, plants, etc.) were traditionally considered as individual beings, Margulis affirmed that they were self-organizing communities of cells, being the true motor of evolution.

This theory came into contradiction with the most established studies on the evolutionary synthesis. Among the classical postulates that he criticized is gradualism, since for Margulis the symbiotic processes were abrupt and happened in relatively short periods of time.

Gaia hypothesis

Although not her creator Margulis, she supported and collaborated to extend the so-called Gaia hypothesis developed by Lovelock. In addition, he contributed his own vision pointing to the bacteria as the main responsible for the chemical type transformations that take place in the biosphere.

This hypothesis indicates that it is life itself that has modified the conditions of the Earth. Instead of following the classical approach that indicated that life had appeared because the planet had certain favorable characteristics, the followers of Gaia affirmed that living beings were responsible for the changes that make the Earth a unique case in the system. solar.

In this way, the hypothesis maintains that the environment and life are interacting continuously, forming a whole regardless of whether it is organic or inorganic matter.


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