You can’t meet Barry Arrington’s challenge, because he won’t let you

Barry Arrington posed a challenge to critics of intelligent design:

So, here is my challenge to our opponents: Do you understand ID well enough to pass the Ideological Turing Test? If you think you do, prove it by giving a one paragraph summary of ID in the comments below.

The “Ideological Turing Test” to which he refers is attributed to Bryan Caplan:

The Ideological Turing Test is a concept invented by Bryan Caplan to test whether a political or ideological partisan correctly understands the arguments of his or her intellectual adversaries. The partisan is invited to answer questions or write an essay posing as his opposite number; if neutral judges cannot tell the difference between the partisan’s answers and the answers of the opposite number, the candidate is judged to correctly understand the opposing side. [link in the original]

As I’ve mentioned before, I try to present my opponents’ arguments honestly, so I felt pretty up to the challenge:

screenshot-2016-11-29-13-04-46

Screenshot from http://www.uncommondescent.com/intelligent-design/ideological-turing-test/ at 1:04 pm EST.

Either Arrington doesn’t want his narrative spoiled, or he doesn’t want to be reminded of what he’s said in the past, because he deleted my comment:

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What is a (Volvox) species?

Hisayoshi Nozaki and colleagues have just described some Volvox samples from two lakes and a pond in Japan.

Figure 1A from Nozaki et al. 2016. Volvox sp. Sagami asexual spheroid with daughter colonies (d).

Figure 1A from Nozaki et al. 2016. Volvox sp. Sagami asexual spheroid with daughter colonies (d).

The newly collected strains have a lot in common with another recently described species, Volvox ferrisii, but there are some important differences as well:

…it could be clearly distinguished from all previously described monoecious species of Volvox sect. Volvox by its small number of eggs or zygotes (5–25) in sexual spheroids, with short acute spines (up to 3 μm long) on the zygote walls and elongated anterior somatic cells in asexual spheroids.

In spite of these differences, Nozaki and colleagues stop short of calling the newly collected strains a new species. Why?

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It’s not evolution, just adaptation

…”evolve” is not the correct term. The microbes adapted. – Cornelius Hunter

We heard several accusations during the recent Presidential campaign that one or the other candidate, or an interviewer, had taken a quote out of context. Of course, every quote is taken out of context. That’s what a quote is; otherwise it’s just the whole speech, or interview, or whatever. The important question is whether or not it’s taken out of context in a way that changes its meaning.

One thing I don’t do, and never have done, on this blog is intentionally misrepresent other people’s positions.  The quote above, from a recent post by Cornelius Hunter on Evolution News and Views, means just what it says. He really is arguing that microbial adaptation observed in Lenski-style experiments is not evolution.

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Initiation of cell division in Chlamydomonas

Deborah Shelton and colleagues have published a new article arguing that the reigning model of cell division initiation in Chlamydomonas reinhardtii needs to be revised [full disclosure: Dr. Shelton and I were labmates in Rick Michod’s lab at the University of Arizona]. The evolution of multicellularity almost certainly involved changes in cell cycle regulation; for example, there is good evidence that changes to the cell cycle regulator retinoblastoma were involved in the initial transition to multicellular life in the volvocine algae. So understanding cell cycle regulation is vital for understanding the evolution of multicellularity.

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Spheroids without inversion: Astrephomene development

Algae in the family Volvocaceae are (with one exception) little spheroids that swim around in freshwater lakes, ponds, and puddles. Volvox is by far the most famous of these algae, but there are a number of smaller genera, including Eudorina, Pleodorina, and Pandorina:

Fig. 1 from Herron 2016. Examples of volvocine species. (A) Chlamydomonas reinhardtii, (B) Gonium pectorale, (C) Astrephomene gubernaculiferum, (D) Pan- dorina morum, (E) Volvulina compacta, (F) Platydorina caudata, (G) Yamagishiella unicocca, (H) Colemanosphaera charkowiensis, (I) Eudorina elegans, (J) Pleodorina starrii, (K) Volvox barberi, (L) Volvox ovalis, (M) Volvox gigas, (N) Volvox aureus, (O) Volvox carteri. Figure Credit for A and B: Deborah Shelton.

Fig. 1 from Herron 2016. Examples of volvocine species; D-O are in the family Volvocaceae. (A) Chlamydomonas reinhardtii, (B) Gonium pectorale, (C) Astrephomene gubernaculiferum, (D) Pandorina morum, (E) Volvulina compacta, (F) Platydorina caudata, (G) Yamagishiella unicocca, (H) Colemanosphaera charkowiensis, (I) Eudorina elegans, (J) Pleodorina starrii, (K) Volvox barberi, (L) Volvox ovalis, (M) Volvox gigas, (N) Volvox aureus, (O) Volvox carteri. Figure Credit for A and B: Deborah Shelton.

All of the members of this family have a problem: at the end of cell division, they find themselves in an awkward configuration, with their flagella on the inside. Each cell has two flagella, and the algae need them on the outside to be able to swim. They achieve this through a developmental process called inversion, essentially turning themselves completely inside-out during embryogenesis. Even the one member of the family that is not spheroidal, Platydorina (F in the figure above), undergoes inversion before flattening into a horseshoe shape. The ways in which they do this are complex and diverse (see for example “Pleodorina inversion” and “The most important time of your life“), but not the topic of this post.

The sister group to the Volvocaceae, the Goniaceae, also includes a spheroidal genus, Astrephomene (C in the figure above). Although Astrephomene looks a lot like some of the Volvocaceae, say Eudorina (I) or Pleodorina (J), it doesn’t undergo inversion!

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Hapalochloris nozakii

Dr. Hisayoshi Nozaki catching a quick nap during the Second International Volvox Meeting in New Brunswick.

Dr. Hisayoshi Nozaki catching a quick nap during the Second International Volvox Meeting in New Brunswick.

University of Tokyo Professor Hisayoshi Nozaki and his colleagues are responsible for describing a large portion of the known diversity of the volvocine algae (see New Volvox species). He described a new species of Astrephomene when he was in high school, leading me to ask him if ‘high school’ meant something different in Japan (it doesn’t). Ironically, since Dr. Nozaki has named numerous species after other people (e.g. Richard Starr, David and Marilyn Kirk, Patrick Ferris, Annette Coleman…), there are, to my knowledge, no species named after him!

Until now, that is: a new paper by Takashi Nakada and Masaru Tomita in the Journal of Phycology introduces Hapalochloris nozakii. This is not just a new species but a new genus, and the bonus is the abbreviated form: H. nozakii.

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