Not much information

GTENS alert

CNN has the story now, but no real details:

Georgia Tech police urged students to stay inside and lock their doors as violent protests erupted Monday on campus after the fatal shooting of a student by police over the weekend. There was a planned vigil for the slain student on Monday.

That’s really all there is that we didn’t already know.

By the way (in case my mom is reading) I’m at home, a mile from campus.

A confused mess, part 2

xkcd Wrong on the Internet

Comic by Randall Munroe, xkcd (of course).

Maybe by the time I have part 2 written up, someone will tell me in the comments why we evolutionary biologists shouldn’t just hang up our hats in light of pre-antibiotic antibiotic resistance.

I really didn’t mean to leave that hanging for three weeks. That was the end of part 1 of my look at Phillip Cunningham’s video, “Darwin vs. Microbes,” in which Cunningham argues that antibiotic resistance is not an example of evolution because (among other reasons),

…contrary to Darwinian thought, it is now found that antibiotic resistance, instead of being an ability that is new for bacteria, is an ability that is ancient.

Boom, game over, creationists win, right? I mean, how can antibiotic resistance have evolved millions of years ago if Alexander Fleming didn’t invent penicillin until 1928? [Read more…]

In which I agree with Michael Egnor

Can you be good without God? Of the various questions raised in the theist/atheist debate, this question has, I believe, occasioned more witless commentary than any other.

–Michael Egnor, Evolution News & Views 2017-09-05

I couldn’t agree more. And you’ll find no better example of that witless commentary than Egnor’s article itself.

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Another step toward understanding sex determination in Volvox

Volvox and its relatives are a great model system for understanding the evolution of multicellularity. Their simplicity (relative to most other multicellular groups) and the variety of ‘intermediate’ species (‘intermediate’ in terms of size and complexity) make them especially suitable for comparative studies of their morphology, development, genetics, genomics, and so on. David Kirk’s book on the topic thoroughly reviews the work done up through the late ’90s, and advances since then have only increased the pace of discovery.

But in the last ten years or so, I would argue that the volvocine algae have emerged as a leading model system for an entirely different set of questions related to the evolution of the sexes. Males and females are defined by the gametes they produce, and the sexes came into existence when their gametes diverged into two different types. The existence of different male and female gametes (sperm and eggs, in most cases) is called anisogamy, and the ancestral condition of similar gametes is isogamy.

In 2006, Hisayoshi Nozaki and colleagues reported that volvocine males evolved from the minus (isogamous) mating type. To the best of my knowledge, this is the only group for which we know this. Since then, more clues have been forthcoming, and these were competently reviewed last year by Takashi Hamaji and colleagues. A new paper in PLoS ONE, by Kayoko Yamamoto and colleagues, adds another piece to the puzzle.

Figure S2 from Yamamoto et al. 2017. Light microscopic images of Volvox africanus (homothallic, monoecious with males type) and V. reticuliferus (heterothallic, dioecious type). Scale bars = 50 μm. sp: sperm packet, e: egg. A-C. V. africanus strain 2013-0703-VO4. A. Asexual spheroid. B. Monoecious spheroid. C. Male spheroid. D, E. V. reticuliferus. D. Male spheroid in male strain VO123-F1-7. E. Female spheroid in female strain VO123-F1-6.

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Two university responses to Charlottesville

Is it fair to judge everyone who marched against the removal of a Confederate monument in Charlottesville? Surely not everyone involved self-identifies as a white supremacist or Nazi. When I marched for science in Washington, DC, I didn’t agree with every single thing that was said on stage or written on signs, but I marched anyway. Same thing, right?

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Volvox 2017 pictures

The Fourth International Volvox Meeting in St. Louis was everything I hoped. It was well organized, small enough to talk to everyone, and full of great talks. David Kirk was indeed there, briefly, though I failed to get a photo, and so was David Queller.

I thought I was pretty connected in the (relatively small) Volvox world, but there were several people there I’d never met and lots of research that was news to me. I’ll be blogging more about some of that research, but for now I’ll just share a few photos from the meeting.

Danforth Center

The Donald Danforth Plant Science Center is the perfect setting for a movie with scientist working on super high-tech stuff.

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