I know this is a horrible photo — I just snapped a picture of the journal hardcopy, which I own, instead of grabbing a PDF from the web, because it’s from 1985 and I’d have to pay to get a copy of my own paper — but this is what I was doing in grad school. I started as somebody who was interested in neurons and the nervous system, so what you’re seeing is a transverse section of the spinal cord of a zebrafish, with a couple of motoneurons labeled black with a tracer enzyme. I spent most of my time teasing apart how those cells grew and made connections.

But all the while there was this one prominent feature of the animal that kept trying to distract me. See that big clear white space below the spinal cord? That’s the notochord. It’s huge, a long transparent cylinder built like a stack of glass coins, running from the neighborhood of the hindbrain all the way back to the tip of the tail. The image from Stemple below is much clearer, since the notochord has been painted pink.

Its superficial function is obvious: it’s a springy rod that the muscles of the fish’s body act upon for swimming and escape behaviors. While I was just doing neural circuitry work, that was sufficient — it’s part of the motor apparatus. Neurons make muscles twitch which flexes the notochord and generates the back and forth motion that propels the animal through the water. Case solved.

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It’s my first completely free day of Christmas break! Grades are all submitted, nothing is hanging over my head, but I still got up at 5:30am and needed to do something, so I learned about spider gastrulation.

This was a disgraceful gap in my knowledge — I’ve worked on insects and on vertebrates, and am fairly familiar with gastrulation in those kinds of organisms, but one thing I did know is that there’s a lot of variation in the details of gastrulation, so every new clade seems to exhibit some novel way of tucking cells in to the early embryo. Spiders do it in a cool way.

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That’s a direct quote from Minnesota’s own Powerline Blog, and I don’t think they were aware of the irony. I think they think they were referring to this chart, which demonstrates the correlation between CO₂ levels and global temperature change over the last century or so.

Thats actually good chart design: axes are appropriate, a lot of data is packed into it very cleanly, and you can see the relationships clearly. Powerline doesn’t like that.

Looks pretty persuasive, doesn’t it? The casual observer would think that we are looking at record levels of CO2–which is not a pollutant, but rather makes like on Earth possible–and record high temperatures. How can anyone dispute the causal connection?

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He’s very concerned about World War III…but not because of the horrific loss of life or the destruction of civilization, but because it might set back plans to colonize Mars. Therefore, we have to hurry up and get humankind into space before we blow ourselves up.

I don’t think we can discount the possibility of a third World War. You know, in 1912 they were proclaiming a new age of peace and prosperity, saying that it was a golden age, war was over. And then you had World War I followed by World War II followed by the Cold War. So I think we need to acknowledge that there’s certainly a possibility of a third World War, and if that does occur it could be far worse than anything that’s happened before. Let’s say nuclear weapons are used. I mean, there could be a very powerful social movement that’s anti-technology.

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Everyone is talking about that stupid town that voted against solar energy because it would suck up the energy of the sun. So I read the story from the local paper, and hey, it wasn’t as stupid as it was made out to be, and there are actually valid arguments against solar farms.

I’m entirely in favor of more wind and solar power, but let’s not pretend there are no problems with them. The residents of Woodland, NC brought up real concerns.

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