It’s symbiosis week!

Yesterday’s lecture began with a dilemma. The topic this week is all about symbiosis, so of course I had to talk about Lynn Margulis, a very complicated person. I have a lot of respect for her contributions to the field, but also had to mention some of her wrong ideas, like that 9/11 was a false flag operation, and that AIDS was caused by a spirochete. It was also a dilemma back in 2007, when Margulis was a guest on this blog and also on our IRC channel. Whew, that was awkward. There might be a few old timers here who remember that.

Also awkward: most of the students had never heard of Margulis until now (they also had no idea what IRC was). At least I got to expose them to a little significant scientific history, which is my job, even when Margulis expressed the opinion that “I believe at all zoologists are intrinsically poorly educated in biology and that medical people are misinformed.” Ouch. There’s a grain of truth there, but mainly my students got to learn that some famous scientists can be colossal dicks. I did tell my students that if she were alive today she’d be a popular guest on Joe Rogan’s awful show.

Anyway, duty done, I lectured on mycorrhizae and gut microbiomes and a lot on Wolbachia. The paper of the week that the students will be telling me all about on Friday is “Eco-Evo-Devo: developmental symbiosis and developmental plasticity as evolutionary agents” by Gilbert, Bosch, and Ledón-Rettig, which you can read if you want to catch up on the course.


  1. chrislawson says

    Wolbachia are amazing. Are you going to talk about them inducing parthenogenesis in certain wasps?

  2. chrislawson says

    It’s sad that Margulis is not better known. I think Sagan said that her key trait was unwavering persistence, which was good for theories like endosymbiosis but not so good for theories like AIDS being due to a spirochete.

    I found this interesting paper on the history of endosymbiosis theories. The authors are spruiking for a ‘hydrogen hypothesis’ which I don’t know enough about to judge. If their history is correct, the first solid intimation of endosymbiotic theory was in 1883, and the first well-developed theory was in 1905! The killer evidence wasn’t available until decades later, specifically that mitochondria have their own genome, closer to prokaryotic bacterial genomes than the nuclear genome of eukaryotes, and reproduce within cells by binary fission.

    Another great paper on a different kind of endosymbiosis: viral capture by parasitic wasps. The wasp and the virus mutually benefit by impairing the immune response of caterpillars to the point that the virus is now incorporated directly within the wasp’s genome. (Content warning for a grotesque image of a caterpillar swarming with wasp pupae.) The original viral integration seems to have happened over 100 Mya, followed by a speciation event about 17 Mya that has led to increasing divergence in the integration and expression of the viral genes.

  3. raven says

    Someone already beat me to it.

    Lynn Margulis/Carl Sagan/Marriage
    June 16, 1957 – 1964
    Margulis was raised in Chicago. Intellectually precocious, she graduated with a bachelor’s degree from the University of Chicago in 1957. Soon after, she married American astronomer Carl Sagan, with whom she had two children; one, Dorion, would become her frequent collaborator. The couple divorced in 1964.

    Lynn Margulis | American Microbiologist & Evolutionary Biologist
    Britannica › Science › Chemistry

    Lynn Margulis was married to Carl Sagan. Yes, that Carl Sagan.

    At least you can say that her life was a wild ride.
    And both very right and very wrong.

  4. birgerjohansson says

    Symbiosis… have you paid any attention to the recent discovery of small viroid-like objects (but not viroids) in humans?

  5. Artor says

    Now I am imagining what a parasitic kitten infection might be like. My mind is going weird places.

  6. Walter Solomon says

    Her Gaia hypothesis is interesting.

    She also made a great point that if humanity ever accomplishes long-term space travel, the interior of the space ships would likely bare little resemblance to those shown in film/TV space operas.

    There would likely be far more plant life onboard, she explains, to provide and food and oxygen.

  7. Jennifer Monroe says

    To add to the comment from @Raven – Margulis also said “I quit my job as a wife, twice. It’s not humanly possible to be a good wife, a good mother, and a first-class scientist; no one can do it. Something has to go.”

    Her persistence in proving what was considered a fringe theory during a time when women weren’t even allowed to take genetics at some major universities is still remarkable all these years later.

    She wasn’t perfect, but she’s no Mereschkowski. :)

Leave a Reply