I’ve only just noticed that I have a fondness for food metaphors when talking about development — gastrulation is a peculiar way to make a jelly sandwich, neurulation is like rolling up a burrito, and somite formation is a meatball sub. They sort of illustrate the arrangement of the tissues involved, but of course they all have shortcomings…but then explaining how the metaphor doesn’t work can be just as informative as the metaphor itself.

For instance, early in its development, the vertebrate embryo consists of two epithelial sheets, the epiblast and hypoblast, pressed against each other like two slices of bread. That’s easy to visualize. It also allows me to explain the core idea of an epithelium — a layer of cells tightly linked to one another to form a continuous more or less two dimensional sheet. A lot of animal development is about epithelia folding and contacting other layers. But another important concept is that some cells are not in sheets — they’ve dissociated and are moving in a loose mass surrounded by an extracellular matrix. This is called mesenchyme. Mesenchyme would be the gooey jelly between the two sheet-like bread slices.

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Wasn’t it enough that I read Nessa Carey’s terrible Junk DNA book? It scarred me, it did. But there’s another one out, John Parrington’s The Deeper Genome: Why there is more to the human genome than meets the eye, and no, I REFUSE TO READ IT. I have been reading Larry Moran’s multi-part evisceration of Parrington, though. It’s spectacularly gory. There are bits of Oxford lecturer in pharmacology spattered all over the place.

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NASA has announced the discovery of a distant earth-like planet, Kepler-452b.

Kepler-452b is 60 percent larger in diameter than Earth and is considered a super-Earth-size planet. While its mass and composition are not yet determined, previous research suggests that planets the size of Kepler-452b have a good chance of being rocky.

While Kepler-452b is larger than Earth, its 385-day orbit is only 5 percent longer. The planet is 5 percent farther from its parent star Kepler-452 than Earth is from the Sun. Kepler-452 is 6 billion years old, 1.5 billion years older than our sun, has the same temperature, and is 20 percent brighter and has a diameter 10 percent larger.

“We can think of Kepler-452b as an older, bigger cousin to Earth, providing an opportunity to understand and reflect upon Earth’s evolving environment,” said Jon Jenkins, Kepler data analysis lead at NASA’s Ames Research Center in Moffett Field, California, who led the team that discovered Kepler-452b. “It’s awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; longer than Earth. That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet.”

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Ben Goldacre has once again produced some excellent writing on scientific data — he has written an article on data analysis and deworming trials, and it’s both interesting and important. I’ll be using it in my classes, because I do try to hammer home to my students the importance of an appropriate understanding of statistics.

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This is amusing. A simple study watched people playing the game Halo, and correlated skill at the game with how they treated other men and women players. It turns out that losers tend to be more disparaging of women.

As they watched the games play out and tracked the comments that players made to each other, the researchers observed that — no matter their skill level, or how the game went — men tended to be pretty cordial to each other. Male players who were good at the game also tended to pay compliments to other male and female players.

Some male players, however — the ones who were less-skilled at the game, and performing worse relative their peers — made frequent, nasty comments to the female gamers. In other words, sexist dudes are literally losers.

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SCREEEE SCREEEE SCREEEEEEEEEEE.