Updates to the Volvox carteri Wikipedia page

The last time I looked at the Volvox carteri page on Wikipedia, it was pretty sad:

V carteri

Volvox carteri Wikipedia page as of December 12, 2018.

That was it; just a short intro and a section on sexual reproduction. I also had an undergraduate researcher, Sophia Sukkestad, who needed an end of semester project. I thought that if she worked on the V. carteri page, she’d learn a bit about Volvox, gain some familiarity with the relevant literature, and improve this resource for everyone.

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Volvox: a colony of cells

In 1950, a young assistant professor at Princeton University published an essay about Volvox in Scientific American, “Volvox: a colony of cells.” The essay touches on several themes that will be familiar to regular readers of Fierce Roller, including cellular differentiation, inversion, and what it means to be an individual.

The author was John Tyler Bonner, whose (much) more recent work I’ve written about previously (“Chance favors the minute animalcule: John Tyler Bonner on randomness“).

John Tyler Bonner

John Tyler Bonner, ca. 1957. Image from the Guggenheim Foundation.

Among many other contributions, Bonner was a pioneer in the development of the social amoeba (or cellular slime mold) Dictyostelium discoideum as a model system for multicellular development and cell-cell signaling. A member of the National Academy of Sciences and a fellow of the American Association for the Advancement of Science, he has published over twenty books and mountains of peer-reviewed papers.

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Volvox wall art giveaway!

I had eight prints made (on canvas) of a micrograph I took in grad school of Volvox aureus. They turned out much better than I expected…it’s really hard to know how the color balance of something you’re looking at on a computer screen will look when it’s printed out. I’m going to give one away by random drawing. All you have to do to enter is leave a comment identifying your favorite species (of anything; rules below).

Volvox aureus

Volvox aureus by me

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Volvox email

I got an email from a science teacher in India. This is the internet being what we thought it would be in the 1990s. I did my best to answer, but feel free to weigh in in the comments.

Dear Matthew,

This is Subhashini, I am a science teacher and a content writer for higher secondary school in India. I have gone through your research papers about Volvox. I still have few questions about Volvox. As I do not want children to get confused need some clarification. I would appreciate if you can help me in answering few questions regarding the same.

Q.1 Is Volvox unicellular, multicellular or colonial organism? Why? (I understand the evolutionary process and the relation of the same but need the explanation about specific cellularity.)

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David Kirk obituary from WUStL

David Kirk

David Kirk. Image from schoolpartnership.wustl.edu.

Washington University in St. Louis’s The Source has published an obituary of Dr. David Kirk, who died November 1, by Myra Lopez:

Kirk, who was an active and passionate member of the university community for nearly 50 years, spent a lifetime teaching developmental biology and researching the evolutionary origins of multicellular organisms. He was internationally known for his research on the spherical green alga known as Volvox carteri.

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This awkward condition

I’ve written several times about the process of inversion that occurs during the development of algae in the family Volvocaceae. Today I was going through a paper I’d read (and even written about) before, and I came across a turn of phrase I appreciated regarding inversion:

The fully cleaved embryo contains all of the cells of both types that will be present in an adult but it is inside out with respect to the adult configuration. This awkward condition is quickly corrected by a gastrulation-like inversion process.

The quote is from Benjamin Klein, Daniel Wibberg, and Armin Hallmann’s 2017 paper, “Whole transcriptome RNA-Seq analysis reveals extensive cell type-specific compartmentalization in Volvox carteri.” Setting aside that animal gastrulation and Volvox inversion may not be as similar as they are often portrayed, I love the description of inside-out colonies as “awkward”. As if they just realized they left the house with their shirt half tucked in and inversion is their way of saying “Excuse me while I get myself sorted out here.”

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Waltzing Volvox

I can’t believe I haven’t already blogged about this, but if I have it isn’t turning up in my searches. Ravi Balasubramanian’s preprint about “flocking” behavior in Volvox barberi mentioned that

V[olvox] carteri is capable of using fluid forces created by flagellar beating to form waltzing pairs.

He’s referring to a 2009 paper by Knut Drescher and colleagues in Physical Review Letters. Drescher and colleagues analyzed the physics that cause Volvox colonies to enter a hydrodynamically bound state in which two or more spheroids orbit each other in close proximity:

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Alternative patterns of explanation for major transitions

The Major Transitions in Evolution Revisited

One reason to study green algae is because they can teach us something about the evolution of multicellularity. A number of related species in the Volvocalean family form a gradation of complexity between single-celled and simple multicellular organisms. The members of this family of algae differ in size, the number of cells they produce, and whether or not there is a split between germline and somatic cells. This split is thought to be central to understanding how a new level of individuality has evolved. — Calcott 2011, p. 39.

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