Morphological embryology of a sea spider

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Tanystylum bealensis male, ventral view, showing eggs and instar 1 (protonymphon) on
ovigerous legs. in. 1, instar 1 (protonymphon); pa, palp; pr, proboscis; 1, first walking leg; 2, second
walking leg; 3, third walking leg; 4, fourth walking leg.

Surely, you haven’t had enough information about pycnogonids yet, have you? Here’s another species, Tanystylum bealensis, collected off the British Columbian coast. That’s a ventral view of the male, and those bunches of grapes everywhere are eggs and babies—males do the childcare in this group. These animals also live in relatively shallow water, in the lower intertidal zone, so it was possible to collect thousands of them and develop a complete staging series. Below the fold I’ve put some illustrations of the larvae, which are even cuter.

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Sea spiders in the news

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Pycnogonids really are fascinating animals and they deserve more attention. There’s a short news article on sea spiders that mentions their odd life style and their taxonomic awkwardness.

For over 100 years, scientists have been puzzling over how exactly to classify sea spiders or pycnogonids.

They crawl along the bottom of the sea floor, sometimes more than 6000 to 7000 metres down, where they live in the dark, feeding on slow-moving soft-bodied sponges and sea slugs.

The creatures are segmented and have an exoskeleton, which makes them an arthropod, the same grouping as crustaceans, insects, centipedes and spiders.

But they also have a very strange collection of features, including a unique feeding structure.

“They have a proboscis that’s like a straw that they insert into the animals and suck out the juices,” says Arango.

Such features make it difficult to fit them into any of the known groups of arthropods.

“They look like spiders, but they are not real spiders,” says Arango. “It’s been very hard to place them in a position within the tree of life.”

They really are hard to place—I’ve reviewed two articles on that subject, one that places them with the anomalocarids and another that groups them more conventionally, with the chelicerates (I’m going with that last one right now—patterns of Hox expression trump interpretations of innervation patterns, I think.)

Would you let Foucault or Derrida treat your cancer?

Martin Rundkvist has discovered a peculiar little paper. It’s titled “Deconstructing the evidence-based discourse in health sciences: truth, power and fascism”, and here’s part of the abstract:

Background Drawing on the work of the late French philosophers Deleuze and
Guattari, the objective of this paper is to demonstrate that the evidence-based movement
in the health sciences is outrageously exclusionary and dangerously normative with regards
to scientific knowledge. As such, we assert that the evidence-based movement in health
sciences constitutes a good example of microfascism at play in the contemporary scientific
arena.

Objective The philosophical work of Deleuze and Guattari proves to be useful in showing
how health sciences are colonised (territorialised) by an all-encompassing scientific research
paradigm — that of post-positivism — but also and foremost in showing the process by
which a dominant ideology comes to exclude alternative forms of knowledge, therefore
acting as a fascist structure.

It’s a paper that objects to the hegemony of EBM. That’s “Evidence Based Medicine” to you and me. The authors also resent the reliance on RCT—Randomized Clinical Trials. This is so strange that I had to read the whole thing.

Yes, I actually did.

And, you know, there actually is a teeny-tiny germ of a worthwhile idea imbedded in it. It’s sloshing about in the midst of a lot of impenetrable jargon, misplaced complaints about reliance on that horrid bug-a-boo, “evidence,” and worst of all, utterly outrageous accusations of fascism and references to Hitler and Mussolini, and talk about terror and totalitarian violence. It’s a bit overblown, but here’s one interesting point:

Of course, we do not wish to deny the material and objective existence of the world [that’s a relief, since he had just finished complaining about the people who are wedded to ‘evidence’], but would suggest, rather, that our relation to the world and to others is always mediated, never direct or wholly transparent. Indeed, the sociocultural forms of this mediation would play a large part in the way the world appears as full of significance. Empirical facts alone are quantities that eclipse our qualitative and vital being-in-the-world. For example, how should a woman assign meaning to the diagnosis she just received that, genetically, she has a 40% probability of developing breast cancer in her lifetime? What will this number mean in real terms, when she is asked to evaluate the meaning of such personal risk in the context of her entire life, a life whose value and duration are themselves impossible factors in the equation?

That’s actually useful to think about. Unfortunately, the ultimate grand failing of this paper is that it doesn’t present much thought about the questions, and proposes absolutely nothing to complement or replace that ol’ Evidence Based Medicine…the only message I got out of it was that the authors felt like complaining about those mean doctors and granting agencies that demand evidence for treatments.

I must be one of those evidence-demanding fascists, because my first thoughts on reading his question were that 1) evaluating the meaning of one’s entire life is something that can be done without demanding the suspension of evidence-based prospective treatments, and 2) isn’t this exactly the kind of situation that other ol’ fascist, Stephen J. Gould, found himself in when he was diagnosed with mesothelioma? He describes the process he went through in The Median Isn’t the Message, and it seems to me that he found the honest answers to his problem in the evidence, the data, and the assistance of modern medical care.

That’s a more productive and useful attitude than complaints about modern medicine as tools of 20th century totalitarianism, which is all this paper has to offer. There certainly isn’t any discussion of any alternatives.

Smacking down more lies about Plan B

It’s really not that hard to understand, but what’s blocking acceptance are the amazing lies people say about Plan B emergency contraception. Ema found a ghastly op-ed that got everything wrong; try reading my summary of Plan B, then the op-ed by Abby Wisse Schachter, and see if you can spot all the errors. You won’t be as thorough as Ema, though, who has posted a wonderfully detailed, complete annihilation of Schachter’s article.

Why does Teresa Nielsen Hayden hate America?

She’s full of advice for terrrarists on state of matter. Now in addition to confiscating our toothpaste, the security people at the airport are going to make us pee into a chromatograph before they let us on the plane.

Let’s just end the slow, lingering buildup and cut straight to the final requirement. Before we can fly, make us all strip naked, take a diuretic and laxative and purge ourselves, and then shackle us to our seats before takeoff.

Creationist genetics

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Reading through Good Math, Bad Math, I saw a classic example of creationist foolishness: a fellow who insists that math will vindicate the Bible by proving that π = 3. It reminded me of this old post where a creationist had the thread jumping in her need to prove that the story of Jacob and Laban actually demonstrated a valid form of biblical genetics. So here it is; the original comments are also amusing.

It’s not just the US that is infested with creationists; take a look at Canadian Christianity. Like their southern brethren, they seem to be greatly concerned about homosexuals and evolution; I’m always astounded at how much conservative Christian identity is tied to the denial of civil rights and opposition to science. There are several juicy tidbits of benighted ignorance there, but I’m going to focus on one incredible claim made in an interview with a Kirk Durston, who is apparently a director of some Campus Chrusade for Christ ministry…which, apparently, means he is now a fully qualified creationist biologist. In the interview, he’s asked this leading question:

As you know, evolutionists tend to use ‘evolution’ as a blanket term, without making the crucial distinction between ‘micro-evolution’ (physical changes within a single species) and ‘macro-evolution’ (transformation from one species into another). Because micro-evolution is scientifically provable, they can say that evolutionary theory is legitimate science—and by using the general term ‘evolution,’ they imply that macro-evolution is also legitimate science. Do you think there is sufficient awareness of the fact that there is no concrete evidence for macro-evolution? Are evolutionists simply afraid to admit this to the public—and perhaps to themselves?

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Joe Carter strings together some noise

Joe Carter is making a curiously convoluted argument. He’s trying to get at why the majority of the American public does not accept the theory of evolution, and he’s made a ten part list of reasons, which boils down to placing the blame on the critics of intelligent design creationism. We’re all bad, bad people who are doing a bad, bad job of informing the public and doing a good job of antagonizing them. There is a germ of truth there—I do think we all have to do a better job of educating American citizens—but what makes it a curious and ultimately dishonest argument is that Joe Carter is a creationist. It’s one thing for an evolutionist to complain that the facts are on our side and we’re doing a piss-poor job of communicating them, but it is a weird thing for a creationist to complain that we do a poor job of communicating the facts, while neglecting to mention that the facts are all against his personal view of life’s origins. The impression it leaves is that Joe Carter doesn’t like evolution because those dang ‘Darwinists’ are all poopy-heads.

Let’s go through each of Carter’s 10 complaints (which you can find in parts I, II, and III), and you’ll see that he even bungles the task of putting together a logical argument: it’s loaded with false premises and inconsistencies.

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