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.

Comment problems

As an unexpected and unintended consequence of FreeThought Blogs kicking our old hosting service to the curb, apparently our commenter whitelists have been lost. Fierce Roller is set that I have to approve your first comment, but after that your comments post automatically.

At least that’s the way it’s supposed to work. Without the whitelist, though, WordPress thinks everyone is a first-time commenter (I had to approve a comment from Aeravi yesterday!). So I’m sorry for the inconvenience, but even if you’ve commented before, your next comment is likely to be held in moderation until I see it. So far, I’ve never blocked a comment that wasn’t straight-up spam, so comment away!

Get your story straight, will you?

Here are a few of the things that would or do support intelligent design, according to various authors on Evolution News & Views:

If evolving multicellularity is complicated. — Cornelius Hunter, Anne Gauger

If evolving multicellularity is simple. — Unsigned Evolution News & Views article

If the human and chimpanzee genomes are very different. — Denyse O’Leary, Casey Luskin, David Klinghoffer, Anne Gauger

If the human and chimpanzee genomes are very similar. — Cornelius Hunter

If life is uncommon in the universe. — David Klinghoffer

If life is common in the universe. — David Klinghoffer

So intelligent design is in the enviable position of being supported equally well by mutually exclusive predictions. Heads I win, tails you lose! Now we can add Kirk Dunston to that last entry (“Could Atheism Survive the Discovery of Extraterrestrial Life?“):

[Read more…]

Relief is in sight

For the past week or so, we (FreeThought Blogs) have been having server troubles. Pages often won’t serve, and here in the WordPress interface I often can’t save drafts or add images. Apparently the problem is with our hosting service, which the powers that be are consequently kicking to the curb. According to PZ Myers,

This’ll be mostly invisible and painless, but there might be a brief lockout tomorrow or the day after as the transition is made. The pattern of glitchy interruptions should end early this week.

The sooner the better.

Maybe the dumbest thing I heard this week

Uncommon Descent

And remember, this is the week we learned ‘covfefe‘.

I don’t usually pick on Uncommon Descent. Their posts are too often incoherent; it’s about as sporting as fishing a hatchery pond. As much as I criticize Evolution News and Views, their posts are generally at least understandable. But I can’t resist on this one. A new post from ‘News’ (which I THINK means Denyse O’Leary; that’s never been completely clear to me) complains about a Nature editorial arguing that

As political leaders on either side of the Atlantic set out contrasting positions on science funding, researchers everywhere need to ensure that their voices are heard.

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Ehrenberg on Eudorina

Eudorina elegans, from Ehrenberg 1832.

Eudorina elegans, from Ehrenberg 1832.

Eudorina elegans was described by the German biologist Christian Gottfried Ehrenberg in his Lectures at the Academy of Sciences in Berlin in the years 18301836 (Vorträge in der Akademie der Wissenschaften zu Berlin im Jahre 1830-1836). With the help of Google Translate, here’s what he had to say about it (page 17):

I have also found an eye-shaped form in the family of the epigones, or of the mucous, intestinal infusoria, which have a hairy body. This form of infusoria is also undefined, but it is confused by me, and probably by all previous observers, with Pandorina Morum (Volvox Morum Müller); Less accurate observers also thought they were probably Volvox Globator. I found them in the basin of the animal garden in the spring of this year between conferences. It is quite consistent with the same form, as I see from my drawing made in the Ural, that the animal which I, as Pandorina Morum, from Kyschtym, have doubtless listed in my list of the Russian Infusoria, and I am of the opinion that I had at that time only overlooked the unsuspected eye. The body consists of a gelatinous, globule-shaped sphere, in which a certain number of spherical, green-colored animals are enclosed, each showing a beautiful red, round but small eye, and a simple, long, whirling, or supporting eyelash through the water. The whirling is seen very clearly as soon as a fine, turbid substance is added to the water. To this animal, which is one of the most beautiful infusoria, I have given the generic name Eudorina, in consideration of the closely related eyeless genus Pandorina. The only known species I have called Eudorina argus (beautiful green eye ball).

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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.

[Read more…]