In their own words, part 2

Evolution News & Views

I previously pointed out that Casey Luskin’s “false, straw-man [version] of ID” bears a striking resemblance to intelligent design advocate Michael Behe’s actual definition:

Let me get this straight:

life is so complex, it could not have evolved” is a “false, straw-man version” of

Cells are simply too complex to have evolved.

I promised that I would get to the second part of Luskin’s “straw-man version,”

…therefore it was designed by a supernatural intelligence,

and that’s what I mean to address in this post. Maybe Luskin wasn’t claiming that ID critics mischaracterize the logic that leads ID advocates to reject evolution, but rather that they mistakenly (or deceitfully) portray ID advocates as inferring supernatural causation. If so, he’s not alone. Advocates of intelligent design frequently deny that their theory has anything to do with the supernatural, and they imply that efforts to portray it as such are deceitful or, at best, misinformed.

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Cells, colonies, and clones: individuality in the volvocine algae

Biological Individuality

As I mentioned previously, I have a chapter in the newly published book Biological Individuality, Integrating Scientific, Philosophical, and Historical Perspectives. The chapter was actually written nearly five years ago, but things move more slowly in the philosophy world than that of biology. Finally, though, both the print and electronic versions are now available; here is the electronic version of my chapter. The book currently has no reviews on Amazon, so if you want to give it a read, yours could be the first. If you’re interested in current and historical views on individuality, there is a lot of good stuff in here, including contributions by Scott Lidgard & Lynn Nyhart, Beckett Sterner, Andrew Reynolds, Snait Gissis, Olivier Rieppel, Michael Osborne, Hannah Landecker, Ingo Brigandt, James Elwick, Scott Gilbert, and Alan Love & Ingo Brigandt.

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Volvox 2017: David Kirk will be there

David Kirk

Dr. David Kirk, Professor Emeritus at Washington University in St. Louis.

I just found out from Jim Umen, who’s organizing the Fourth International Volvox Conference, that David Kirk is planning to attend. This is great news; we’ve been wanting Dr. Kirk to come since the first meeting in 2011, but it hasn’t previously worked out.

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Volvox 2017: early registration extended

Volvox 2017

Discounted registration for the Volvox 2017 meeting has been extended to June 16th. This is a pretty good deal as scientific meetings go: $550 for faculty includes registration, most meals, and a shared room. Registration for postdocs and students is $100 less, and there are travel grants available. If you’ve been debating whether or not to go, it’s decision time: prices will go up $100 after the 16th.

New review of green algal sex

Hiroyuki Sekimoto from Japan Women’s University has published a review of sexual reproduction in the volvocine algae and in the Charophyte Closterium in the Journal of Plant Research. In addition to a brief description of the Chlamydomonas sexual cycle, it includes a succinct review of the genetics of sex and sex determination. Unfortunately, the article is paywalled, and my inquiry to the author has so far gone unanswered.

Figure 1 from Sekimoto 2017. The life cycle of Chlamydomonas reinhardtii. Vegetative cells (V) di erentiate into mt+ and mt− gametes (G) during nitrogen starvation (−N). Mating types are restricted by mating-type loci (+ and −). When gametes are mixed, the plus and minus agglutinin mol- ecules on their agellar surfaces adhere to each other, and this adhe- sion results in increased intracellular cAMP levels. The signal trig- gers gamete cell wall release and mating-structure activation. Cells then fuse to form binucleate quadri agellated cells. Zygotes with thick cell walls germinate in response to light and nitrogen supple- mentation, and undergo meiosis to release four haploid vegetative cells

Figure 1 from Sekimoto 2017. The life cycle of Chlamydomonas reinhardtii. Vegetative cells (V) differentiate into mt+ and mt− gametes (G) during nitrogen starvation (−N). Mating types are restricted by mating-type loci (+ and −). When gametes are mixed, the plus and minus agglutinin molecules on their flagellar surfaces adhere to each other, and this adhesion results in increased intracellular cAMP levels. The signal triggers gamete cell wall release and mating-structure activation. Cells then fuse to form binucleate quadriflagellated cells. Zygotes with thick cell walls germinate in response to light and nitrogen supplementation, and undergo meiosis to release four haploid vegetative cells.

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Convergence falsifies evolution, according to Cornelius Hunter

Xerus princeps

Xerus princeps, the mountain ground squirrel.

Before I saw the light and switched to studying Volvox, I studied squirrels. With apologies to Iris Vander Pluym, squirrels are cool. If you grew up in the squirrel-deprived eastern U.S., you might not realize that there are over a hundred species. Chipmunks are squirrels. Marmots are fat squirrels. Prairie dogs are adorable squirrels.

Most of my squirrel work, and some of my Volvox work, has focused on understanding the evolutionary relationships among species. This fits in the subfield of evolutionary biology known as phylogenetics. Phylogenetics results are often visualized as trees and published in journals like CladisticsMolecular Phylogenetics and Evolution, and Systematic Biology. Phylogenetics is a vast subfield, with a huge number of papers devoted to developing methods that are theoretically and empirically sound.

Cornelius Hunter understands none of this. In a recent post over at Evolution News and Science Today (which used to be Evolution News and Views…when did that change?), he argues against the whole idea of common descent, the very foundation of phylogenetics. Dr. Hunter argues that convergence, similarities among distantly related species, falsifies evolution. The nature of his arguments shows pretty conclusively that he doesn’t understand the basic logic of what he’s criticizing.

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Rediscovered after two thirds of a century: Pleodorina sphaerica

Pleodorina sphaerica

Figure 1 from Nozaki et al. 2017. Pleodorina sphaerica.

There really aren’t enough people looking for volvocine algae. There’s a suspicious tendency for the geographical centers of volvocine diversity — southern Africa, central North America, southeast Asia — to include the home institutions of phycologists studying volvocine diversity — Mary Pocock, Richard Starr, Hisayoshi Nozaki, respectively. I find it much more likely that this is an artifact of sampling effort than that, for example, central Africa and Central and South America are depauperate of volvocine algae.

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Look what came in the mail yesterday!

Biological Individuality

A project started five years ago has finally borne fruit. In May, 2012 I joined a group of philosophers, historians, and biologists in Philadelphia for the Cain ConferenceE pluribus unum: Bringing biological parts and wholes into historical and philosophical perspective.” The meeting was organized by Lynn Nyhart and Scott Lidgard, with the goal

…to pursue the question: How can historians, philosophers, and biologists help each other to understand part-whole relationships in biology, both today and in the past?

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Volvox 2017: one week left for early registration

Volvox 2017 LogoJust what the headline says: early registration for The Fourth International Volvox Conference ends May 19th. After that, prices go up $100 for everybody. The registration fees sound a bit steep (up to $650), but when you consider that they include meals, lodging, and transportation between the hotel and the conference, they’re not bad at all:

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Devolution isn’t a thing

Devo

Yesterday I volunteered as a Meeting Mentor at the AbSciCon meeting. It’s not a big commitment; essentially all you have to do is hang out with a high school student for half a day, going to talks and enjoying the meeting as you normally would.

During a break, I was chatting with my mentee about Betül Kaçar’s research, and he surprised me by pointing out that (as he put it), “Devolution isn’t a thing.” The student I was paired with is interested in physics and space exploration, but his comment showed an insight that not even all professional biologists really own. From what I’ve seen, it’s an insight that very few creationists own.

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