Isn’t pleiotropy handy?

Look at the interesting snake found in China — it’s got a leg.

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How can this happen? Genes are pleiotropic — they tend to have lots of different functions. The genes involved in making a limb are also expressed in other places; for instance, the Hox genes that specify identity along the length of the body are also reused in specifying identity along the length of the limb. What that means is that when the snake evolved limblessness, it didn’t do so by simply throwing away a collection of leg genes — it couldn’t, not without also destroying genes that functioned in generating its body plan. Instead, it evolved genes or modified the regulation of genes to actively suppress limb development…but the genes to build a limb are still in the genome, and still functional, and still actively working in other ways.

What most likely happened here is that some environmental agent suppressed the suppressor, allowing the old developmental program for a limb to be re-expressed. The retention of such programs is, of course, evidence that this animal evolved from limbed ancestors.

It would be interesting to know what triggered this change. It’s not likely to be genetic (the asymmetry suggests that), but is probably a consequence of some pollutants that disrupt development. It’s not a good sign, anyway.


Some good suggestions from the comments: it may not even be a teratogenic deformity. It could just be a poor lizard that punched a claw through the abdominal wall as it was being digested, and the snake was briefly trundling about in pain from the injury.

We need to do a dissection!

How to save the California Condor

We just have to make the practice of sky burial popular! Maybe this photo set of a Tibetan funeral will help. (WARNING! Those photos show a large flock of vultures stripping a human body of flesh, with the assistance of some helpful Tibetans who break up the larger bones with hatchets. Don’t click on the link if you are at all squeamish.)

Boy, those are some happy vultures. I think I’d like to bring a little joy into the life a few carrion-feeders after I die, too.


Ooops, another warning: I’d looked at it with an adblocker, so I hadn’t noticed the very in-your-face porn ads on the page, so my apologies. I wouldn’t have thought it worth worrying over if it were just pictures of naked people, but ads that treat women like pieces of meat are far more revolting than corpses getting eaten by big birds.

Inspiration for student groups

Someone needs to start an organization with this name just so they can use this logo that I got from Glynn Lane:

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Students could join, and then they could all run out and get these t-shirts:

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Unfortunately, there’s pretty much nothing we could do to be even creepier than that other, better known Campus Crusade for some guy.

God works in mysterious ways

A very devout Catholic was trapped on an elevator for a while, and after it was working again, rushed to church to thank God. Then, something unfortunate happened:

He seems to have embraced a stone pillar on which the stone altar was perched and it fell on him, killing him instantly. We have found his fingerprints on the pillar. We are now investigating the case further.

Now, you see, if he’d rushed off to thank the elevator repairman, that wouldn’t have happened. Given his bad luck, the repairman might have been a demented homicidal maniac who would have clubbed him to death with a spanner, but no altar would have fallen on him. Therefore, religion is bad for your health.

Fairies and Bigfoot

Speaking of being underwhelmed by the arguments, we’ve actually got people arguing for the existence of fairies and bigfoot. They even say they’ve got evidence: here’s the Croydon photo:

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Looks like an ugly flash artifact of an insect caught in flight.

Some guy in Kentucky had a video camera set up to monitor his backyard, and it caught this frame of a purported Bigfoot:

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I have no idea what that blurry blob is…somehow, whenever one of these mysterious creatures is seen, the lucky witness is always either a really awful photographer or is using garbage equipment.

There are some real mysteries here, though. Why was that woman going out to take pictures of her ugly lawn furniture at night, and why does that guy need constant video surveillance of his weedy back yard?