True Facts: The Self-Sacrificing Amoeba

Published 2022-08-04
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Thank you to:
The family of Dr John Bonner, Princeton University…

Dr Jitka Cejkova, University of Chemistry and Technology Prague

Dr Thomas Gregor, Princeton University

Dr Kathie Hodge, Cornell University

Dr Bernard Jenni, Mabritec

Dr Edvin Johannesen, Natural History Museum Oslo

Kent Loeffler, Cornell University…

Alberto Melappioni

Dr Fred Spiegel, University of Arkansas

Cornell Center for Fungal Biology

Education Development Center

TGLab, Princeton University

UMass Amherst Libraries


Bianchi, E., Doe, B., Goulding, D. et al. Juno is the egg Izumo receptor and is essential for mammalian fertilization. Nature 508, 483–487 (2014).

Bloomfield G, Paschke P, Okamoto M, Stevens TJ, Urushihara H. Triparental inheritance in Dictyostelium. Proc Natl Acad Sci U S A. 2019 Feb 5;116(6):2187-2192. doi: 10.1073/pnas.1814425116. Epub 2019 Jan 22. Erratum in: Proc Natl Acad Sci U S A. 2019 Feb 25;: PMID: 30670662; PMCID: PMC6369745.

Bonner, J.. (2008). The social amoebae: The biology of cellular slime molds. The Social Amoebae: The Biology of Cellular Slime Molds.

Dormann D, Weijer CJ. Imaging of cell migration. EMBO J. 2006 Aug 9;25(15):3480-93. doi: 10.1038/sj.emboj.7601227. PMID: 16900100; PMCID: PMC1538568.

Kurato Mohri, Ryodai Tanaka, Seido Nagano, Live cell imaging of cell movement and transdifferentiation during regeneration of an amputated multicellular body of the social amoeba Dictyostelium discoideum, Developmental Biology, Volume 457, Issue 1, 2020, Pages 140-149, ISSN 0012-1606,

Kuwana S, Senoo H, Sawai S, Fukuzawa M. A novel, lineage-primed prestalk cell subtype involved in the morphogenesis of D. discoideum. Dev Biol. 2016 Aug 15;416(2):286-99. doi: 10.1016/j.ydbio.2016.06.032. Epub 2016 Jun 29. PMID: 27373689.

Mori M, Yao T, Mishina T, Endoh H, Tanaka M, Yonezawa N, Shimamoto Y, Yonemura S, Yamagata K, Kitajima TS, Ikawa M. RanGTP and the actin cytoskeleton keep paternal and maternal chromosomes apart during fertilization. J Cell Biol. 2021 Oct 4;220(10):e202012001. doi: 10.1083/jcb.202012001. Epub 2021 Aug 23. PMID: 34424312; PMCID: PMC8404465.

Orvieto, Raoul & Shimon, Chen & Rienstein, Shlomit & Jonish-Grossman, Anat & Shani, Hagit & Aizer, Adva. (2020). Do human embryos have the ability of self- correction?. Reproductive Biology and Endocrinology. 18. 10.1186/s12958-020-00650-8.

Prabhakara, K.H., Gholami, A., Zykov, V.S., & Bodenschatz, E. (2017). Effects of developmental variability on the dynamics and self-organization of cell populations. New Journal of Physics, 19.

Smith TS, Pineda JM, Donaghy AC, Damer CK. Copine A plays a role in the differentiation of stalk cells and the initiation of culmination in Dictyostelium development. BMC Dev Biol. 2010 Jun 2;10:59. doi: 10.1186/1471-213X-10-59. PMID: 20525180; PMCID: PMC2890595.

Raper, Kenneth B., and Dorothy I. Fennell. “Stalk Formation in Dictyostelium.” Bulletin of the Torrey Botanical Club 79, no. 1 (1952): 25–51.

Uchikawa T, Yamamoto A, Inouye K. Origin and function of the stalk-cell vacuole in Dictyostelium. Dev Biol. 2011 Apr 1;352(1):48-57. doi: 10.1016/j.ydbio.2011.01.014. Epub 2011 Jan 21. PMID: 21256841.

All Comments (21)
  • CalderaMan
    My mom and I would always watch these when they came out and loved everyone of them. This is the first one I had to watch without her. I know she would have loved it too.
  • Sandra
    A couple of thoughts:
    1. Can you imagine learning biology in high school from a dude like this?! Would have spawned more scientists and/or improv comedians!
    2. How the heck did they figure this out? The tenacity and perhaps the tedium of all the hypotheses and experiments...I am amazed and humbled.
  • Chris Jeffries
    I did my senior project on Dictyostelium discoidium when I was a Biology major at the Air Force Academy. I got an A. The Biology Department professors loved it. Amazing how they differentiate and work together (the slime molds, not the professors). Thanks for this video. Brough back some great memories.
  • Josué B.A
    When I started watching this series I was in highschool. This year I got my bachelor in Biology! You are still making awesome, inspiring videos! Always a pleasure to watch.
  • Michael Watson
    There is a book, "a short history of nearly everything" that has a part where the author talks to a guy who studies slime molds. The author is somewhat bewildered by the man's interest, but this video totally makes the fascination obvious.
  • Dr. I. B. Safe
    I’m so glad that Jerry and I weren’t left in suspense about the pizza. It perfectly explained the mating habits of a single-cell organism.
  • Pi61
    It's so fascinating that a single-celled organism can have such a complicated herd-ish behavior.
  • Asdis Skagen
    I am old and have only today stumbled upon this goldmine of witty videos. This is almost as good as winning the lottery. I'm just sad that I am only discovering these now, but that's offset by knowing there are now more videos to binge watch. My hat is off to you, Sir - if all science teachers were as entertaining as you, the United States would be entirely made up of science hippies. Cheers!😂
  • Widget
    As always, the little off topic conversations with Jerry really just ties up the whole thing beautifully
  • Miss Bee
    Jerry is full of great questions. Also, “tube-like snot condom” is a series of words that will take the rest of my life to forget…😬
  • Jake Reich
    I spent a couple of years working with Dicty as a post-doc, and this was a good overview of much of their biology!

    One thing I think you missed: not only can they develop to a multicellular structure, but if this process is disrupted, the slug or mound cells will happily de-differentiate back to free-living cells. This is why Dicty are studied with respect to cellular reprogramming and stem cells etc.
  • Robungulus
    I took a class and one unit went very in depth about this species. Some cool follow up facts.

    1. When the “slug” eventually releases its spores, those spores usually carry bacteria in them to sort of “plant” into the new environment and than cultivate as a food source. It’s like a farmer bringing a herd of sheep to new ranch and it is wild.

    2. When two different clone groups create a slug the slug is called a “chimera”

    3. Cheating in this species in chimeras, as explained in the video, is actually one of the single craziest things in biology. The species has developed a handful of ways to combat cheating, for example some genes that result in a clone not helping produce the stalk cause it to adhere less to more altruistic clone types meaning it can’t “piggyback” as well and just falls off the slug. (There are A ton more crazy interactions for cheating and controlling cheating, but this is already too long)
  • S Reeser
    When I was in college, I had a professor who genuinely used True Facts videos in his lesson plans. Awesome teacher. I can already picture him practically jumping for joy about this one!
  • Taran Van Hemert
    Fascinating. It's like a bizzare mash up between single and multicellular life.
  • Damion Lee
    Over the years, these True Facts commentaries just keep getting better. Lots of great information, and some really cleverly constructed visualisations that are simply hilarious. I'll never look at the pizza boy the same way again!
  • Aaron Tobias
    I love how weird single cell organisms are. These guys make me me think that the first multi cellular entities were some of these ‘slugs’ that started to just stay as a slug and hunt bigger prey
  • Stacey Grahame
    “Runaway dog penis.” 😂😂 Just when I think ZeFrank has given us all the crazy yet genius comparisons that he can, he delivers more. 🤣🤣
  • Phoenix
    This system has better organization than a lot of companies I've worked for.
  • It's been amazing watching this series over the years. You started off as an affectionate parody of a Morgan Freeman narration, and you've turned it into your own thing that is both educational and hilarious.