If you’re not an activist, you must be a do-nothing passivist

A True Scientist is supposed to be aloof, objective, dispassionate, and unemotional. This isn’t just a stereotype, it’s part of a set of social mores that are imposed on individuals who belong to this community of scientists.

And yet, at the same time, we’re part of a larger society that sometimes has serious problems that scientists are among the first to see. Should climate scientists be dispassionate about global climate change? Should medical doctors be unemotional about dishonest tobacco advertisements? The best scientists I’ve known have also had causes: for instance, George Streisinger, the fellow who started this whole business of zebrafish as a model system, was also a peace activist who was very concerned about nuclear war.

So when Shiv writes about the use of the word “activist” to demean scientists, I know exactly where that’s coming from. I’ve seen it way too many times.

Being an activist means you are aware and working to change the world. There’s nothing in that that implies you are cavalier with the evidence — often, it means you are acutely conscious of the facts, and passionate about the truth.

Watching zebrafish make stripes

Our summer research program is winding down, and preparation for the fall semester teaching is winding up. My student, Katrine Sjovold, and I have been trying to figure out what early melanocytes are doing — it’s a very simple and accessible system to observe cell motility, because the cells label themselves with melanin and we don’t need to do any of that persnickety cell injection stuff, or buy expensive dyes, or buy expensive cameras capable of detecting fluorescence (although we’ve tried a little of that here at the end of the summer, and I’ve been appropriately impressed that my research camera actually can see DiI fluorescence, even if it’s not designed for it).

Anyway, one of the things we’ve been doing is making time-lapse videos of melanocytes after they start making pigment and as they’re linking up and consolidating to form stripes. Here’s one example, a time-lapse where we take one image every 3 minutes over a day and an evening of growth.

You can see that we’re looking down on the dorsal side of the animal, in the region of the hindbrain (see the fourth ventricle, and the ears, deep and out of focus?). You may also notice that one of the melanocytes spontaneously decides to die and quickly breaks down into a few darkly pigmented blobs.

I’ve also uploaded a few other videos, but keep in mind these aren’t polished, perfect videos — these are bits and piece of our working data collection.

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Let’s all make chimeras

manbearpig

Government regulation of research to enforce ethical concerns is a good idea, and I support the general idea. I’d like them to be based on reasonable concerns, though. I’m actually glad that the NIH has ended a ban on research into human-animal chimeras, although I know some people are going to freak out over it, pointlessly.

Here’s the basic idea. Mammalian embryos are relatively plastic. If you take a mouse embryo at the blastocyst stage, when the embryo is just a small number of cells in a spherical capsule, and you take a few cells from a human blastocyst and inject them into the mouse embryo, those human cells will be readily incorporated into the developing mouse. They can then be incorporated into the mouse’s tissues, so you end up with an adult mouse that has a liver made up of human liver cells. Or a human pancreas. Or, what really scares some people, human-derived brain tissue. Or human-derived gonadal tissue — the mouse could be making human sperm or human eggs, and if a boy mouse with human testes meets a girl mouse with human ovaries…well, you can imagine the concerns.

One issue is that scientists might inadvertently create animals that have partly human brains, endowing them with some semblance of human consciousness or human thinking abilities. Another is that they could develop into animals with human sperm and eggs and breed, producing human embryos or fetuses inside animals or hybrid creatures.

That was the thinking that led to the moratorium on such experiments, now lifted. Which is good.

All of those troubling possibilities are rather easily prevented, and also rather unlikely.

The concerns about animals with “some semblance of human consciousness or human thinking abilities” is simply silly. They already do, and you could also argue that humans have some semblance of animal consciousness. Mice aren’t going to be able to construct whole human brains in their tiny little skulls, although maybe a pig chimera could; but even there, our brains have co-evolved with all kinds of circulatory adaptations, and I rather suspect that a chimera with a significant amount of human brain tissue isn’t going to be viable. And most importantly, the point of such research isn’t to make a human brain in an experimental animal — it’s to get human nervous tissue that will have human-like responses to, for instance, pharmacological treatments.

It’s the same with the reproductive tissue. Making male and female pigs with human reproductive organs would be cool and useful, but bringing them together to do something as mundane as producing a human baby is not — and would be a catastrophic result of the research that would probably lead to the shutting down of the lab and massive legal consequences, all to produce a totally useless result. These are labs that are interested in studying the mechanisms of human sperm maturation, or oocyte development, not the mad scientist nonsense of creating ManBearPig.

Of course, some people don’t like the idea of ending the moratorium.

But critics denounced the decision. “Science fiction writers might have imagined worlds like this — like The Island of Dr. Moreau, Brave New World, Frankenstein,” says Stuart Newman, a biologist at New York Medical College. “There have been speculations. But now they’re becoming more real. And I think that we just can’t say that since it’s possible then let’s do it.”

Let’s do what? That’s the crux of this disagreement — no one is interested in creating The Island of Dr. Moreau in reality. Moreau was an idiot who didn’t do anything practical or informative with his imaginary technology, and using dystopian science fiction as your counter-argument really says you don’t understand the motivations behind this research.

It adds a whole new meaning to the phrase, “The Eagles are coming!”

There’s a webcam that has been watching a nest full of ospreys growing up, and the birds were almost ready to begin their flying lessons. Then…they get a visitor.

Is there a metaphor somewhere in this comment about America’s national bird?

The predation of an Osprey nest by an eagle might come as a surprise to many, but eagles are the ultimate opportunists. “They take what’s around and what’s available,” Kress says. And while the activity from the Audubon Camp located nearby usually keeps them away, in the end, “there’s nothing you can really do.”

Interestingly counter-intuitive

There are a few people I might like to fire into the heart of the sun, but I hadn’t realized how difficult that was. Here’s a video and simple simulator that lets you try to fire a rocket right into the sun. It took me a few tries to figure out how to do it — you have to launch directly opposite to the direction of Earth’s travel, and cancel out its velocity…and then it will fall into the sun. If you’re a fair bit off, it flies off into a new orbit around the sun that intersects with Earth’s orbit, which is not good. If you’re a teeny tiny bit off, it just scarcely grazes the sun, and then something cool happens: it slingshots around at tremendous velocity and flies off the screen.

I mostly sent rockets off to Alpha Centauri, or something, which is not quite as spectacularly destructive as slamming into a giant radioactive ball of plasma. But still good.