Sperm in action

This is a beautifully done movie, although it does get a bit silly in the end.

One point this brought to mind: have you ever looked at sperm? They’re amazing. We humans do go through a single-celled haploid stage which is the focus of some very intense selection pressure, and humans in their haploid phase possess some impressive abilities. No brains, but the sperm are motile and exhibit seeking behavior. Eggs are also wonderful — they are precisely balanced on the edge of criticality, ready to erupt into a cascade of changes with a single stimulus. It’s easy to dismiss gametes as blobs and slime, but they have all the charm and complexity of bacteria … and I say that completely non-ironically.

(via Street Anatomy)

Physics of the Sandman

James Kakalios gets to use the latest Spider-Man movie as an excuse to explain the physics of granular materials in the New York Times. Good thing they didn’t ask a biologist about Sandman … all I could think about was that there was no way a loose aggregate of coarse sand would be able to mimic the function of the human brain, which is built upon the sub-micron-scale specific organization of diverse molecules. I would be such a wet blanket.

No, wait, I did think of another thing: could you incapacitate Sandman by dumping your cat’s litterbox on him? I’d think he’d go running off to do some emergency particle segregation right away.

I will say that the Sandman special effects were the best part of the movie. The rest — plot, acting, dialogue — eh, not so much.

An encyclopedia of life?

I wish I could be more enthusiastic about the Encyclopedia of Life project. It’s to be an online encyclopedia with a substantive page dedicated each species on the planet, and it’s endorsed by E.O. Wilson, with sponsorship from some of the most prestigious museums around. It’s a fantastic idea that would be incredibly useful.

But then …

The demonstration pages are beautiful, maybe too beautiful. There’s the promise of a colossal amount of information in each one, although at this point all they’ve got are very pretty but nonfunctional images of what the page will look like — but you can see that the content is not trivial and the organization is detailed. I browsed the FAQ to see how they’re going to do it, and it’s awfully vague. “Mashups” of existing databases? Recruiting sources from existing online collections? They were inspired by Wikipedia? (No, please no…if it’s wikified it will be useless as a source of technical information.) I look at the money they’ve got — $12 million — and the number of species they aim to catalog — 1.8 million — and it just doesn’t add up to me. Aren’t they going to burn through that much money in just paying for the emergency room visits for the brawling systematists fighting over the ontological issues?

I don’t mean to sound so negative, since I think it’s an eminently laudable goal, but I get very, very suspicious when I see all the initial efforts loaded towards building a pretty front end while the complicated core of the project is kept out of focus. I’d be more impressed with something like NCBI Entrez, which, while not as attractive as the EOL mockups, at least starts with the complicated business of integrating multiple databases. I want to see unlovely functionality first, before they try to entice me with a pretty face.

(via John Logsdon)

Apocryphal elements

If you’re trying to come up with names for an exotic element with amazing properties for that comic book, fantasy novel, or role-playing game you’re writing, here’s a list of apocryphal elements (there’s also a similar list with more details). These are all genuine false alarms from the world of science, guaranteed to have been generated from the twisted minds of actual chemists and physicists.

We really need elements called Ultimium and Extremium. Neokosmium isn’t bad, either.

We have the brains of worms

Way back in the early 19th century, Geoffroy St. Hilaire argued for a radical idea, that vertebrates and most invertebrates were inverted copies of each other. Vertebrates have a dorsal nerve cord and ventral heart, while an insect has a ventral nerve cord and dorsal heart. Could it be that there was a common plan, and that one difference is simply that one is upside down relative to the other? It was an interesting idea, but it didn’t hold up at the time; critics could just enumerate the multitude of differences observable between arthropods and vertebrates and drown out an apparent similarity in a flood of documented differences. Picking out a few superficial similarities and proposing that something just looks like it ought to be so is not a persuasive argument in science.

Something has changed in the almost 200 years since Geoffroy made his suggestion, though: there has been a new flood of molecular data that shows that Geoffroy was right. We’re finding that all animals seem to use the same early molecular signals to define the orientation of the body axis, and that the dorsal-ventral axis is defined by a molecule in the Bmp (Bone Morphogenetic Protein) family. In vertebrates, Bmp is high in concentration along the ventral side of the embryo, opposite the developing nervous system. In arthropods, Bmp (the homolog in insects is called decapentaplegic, or dpp) is high on the dorsal side, which is still opposite the nervous system. At this point, the question of whether the dorsal-ventral axis of the vertebrate and invertebrate body plans have a common origin and whether one is inverted relative to the other has been settled, and the answer is yes.

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True confessions

Oh, I hate these difficult questions.

If you’re a professor and you want to change the world, what do you do? In 1993–quit and become an activist. In 2007—start a blog.

Or so it seems. PZ Myers blogging at Pharyngula is probably doing more for evolution than PZ Myers publishing papers in scientific journals. Is that true PZ?

No.

Hmmm, I guess it wasn’t so difficult after all!

[Read more…]

Twisty maze of duck oviducts

I’m sure you’ve already heard about it, so I’m a little redundant to bring it up — Carl Zimmer has a spiffy article in the NY Times about duck phalluses. No, that’s not quite right; the most interesting part of the story was the bit about duck oviducts. Female ducks have been evolving increasingly convoluted oviducts to baffle the efforts of duck rapists to inseminate them, and male ducks have been evolving concomitantly long phalluses to thread the maze and deliver sperm to the ovaries.

I’d heard about these huge intromittent organs in ducks before, but this is another fascinating revelation: it took a woman scientist to suggest that maybe, just maybe, they also ought to look at what’s going on in the female ducks, and then the whole wonderful story of coevolution of these structures emerged. It’s actually a rather embarrassing instance of a scientific blind spot, where the biases of the investigators led them to overlook an important component of the story.