“In 2002, having spent more than three years in one residence for the first time in my life, I got called for jury duty. I show up on time, ready to serve. When we get to the voir dire, the lawyer says to me, “I see you’re an astrophysicist. What’s that?” I answer, “Astrophysics is the laws of physics, applied to the universe—the Big Bang, black holes, that sort of thing.” Then he asks, “What do you teach at Princeton?” and I say, “I teach a class on the evaluation of evidence and the relative unreliability of eyewitness testimony.” Five minutes later, I’m on the street.
A few years later, jury duty again. The judge states that the defendant is charged with possession of 1,700 milligrams of cocaine. It was found on his body, he was arrested, and he is now on trial. This time, after the Q&A is over, the judge asks us whether there are any questions we’d like to ask the court, and I say, “Yes, Your Honor. Why did you say he was in possession of 1,700 milligrams of cocaine? That equals 1.7 grams. The ‘thousand’ cancels with the ‘milli-’ and you get 1.7 grams, which is less than the weight of a dime.” Again I’m out on the street.”—
True story, I got called in for jury duty myself last month for the first time ever (because going to grad school and basically being a student for ten straight years got disqualified me before) and I was ready to give these exact answers so I could be all…
on the judge, and then they dismissed all the potential jurors without even going to selection and so I was all…
Is congenital myotonia found in non-domesticated animals?
This question comes from my video about GOATS! so you should watch that first to get an intro on fainting goats (congenital myotonia) and also just because goat science is awesome.
I just spent half an hour digging through scientific literature trying to find reports of congenital myotonia (“fainting syndrome”) in a wild animal and came up with exactly zilch, zero, and nada. We see it in goats, horses, dogs, cats, people… all of which are domesticated species (except for maybe people), but no reported cases in wild animals. Does that mean it’s impossible?
First let me summarize what should happen in a normal skeletal muscle contraction, then I’ll answer that question.
Muscle cells, like nerve cells, actively maintain different concentrations of ions on either side of their membrane. This resting membrane potential is super-interesting, but also pretty complicated, so instead of me turning this answer into a textbook chapter, all you need to remember right now is that the inside of a muscle cell is slightly negative compared to the outside. The ions we need to keep in mind right now are sodium (Na+, higher conc. outside), potassium (K+, higher concentration inside), and chloride (Cl-, higher concentration outside).
When a nerve impulse reaches a muscle fiber, the neurotransmitter acetylcholine opens a sodium-specific door on the muscle and lets some Na+ ions inside.
Sodium is a positive ion, so it makes the inside of the muscle more positive. Then that initial burst of Na+ leads to an even larger Na+ wave. Positivity breeds positivity, people!
This burst of positive charge into the muscle cell is essentially what makes it contract (although I’m leaving out a bunch of stuff, like how calcium comes into play, to dig into more detail on all this, check out these great illustrations from MDA.org)
Of course, muscles don’t usually stay contracted, unless you’re dead, diseased, or get a cramp. Why not? After a short amount of time, potassium ions flow out of the cell through their own special potassium doors (making the inside more negative again) and chloride ions move in through their special chloride doors (making the inside even more negative).
It’s the return to that original inside-negative state that makes the muscle relax (now maybe you can start to see why loss of salt/electrolytes can lead to cramps?)
Finally we come to the fainting goats. Congenital myotonia leads to a mutation in that chloride channel I mentioned up there (if you’re into gene and protein names, it’s called CLCN1), meaning that those muscle cells take longer to return to their normal negative-on-the-inside charge and stay locked in the “on” state.
That’s what we see in “fainting” goats, or any other creature with congenital myotonia. The muscles just lock up, and the “fainting” is really just “falling over thanks to suddenly obtaining the flexibility of a statue.”
So does this mutation exist in wild animals? Probably. There’s no reason a wild animal could gain a spontaneous mutation in its chloride channel gene and have particularly rigid offspring. Only these statue-creatures would be easy pickings for predators, as in “easiest meal evar,” and that mutation wouldn’t be able spread throughout the population. Since we can’t keep track of every single wild animal and their offspring, we probably never see it (although there might be isolated reports out there). Like, what’s happening with this panda? I don’t even know.
On the other hand, we inbreed the hell out of domesticated animals, and thanks to fences, sharp sticks, and sheepdogs, we tend to keep them fairly safe from predators (not to mention that humans don’t have any predators except each other). So whether or not they have the genetic misfortune of crumpling into a heap of myotonic hilarity every time we sneak up behind them, we’ve artificially (and accidentally) amplified this mutation in domesticated breeds (although breeders are often encouraged to not breed “fainting” animals).
So the answer to your question is almost certainly yes, although the Bad Wolves keep the Weeping Angels from taking over.
“There was a smell of Time in the air tonight. He smiled and turned the fancy in his mind. There was a thought. What did Time smell like? Like dust and clocks and people. And if you wondered what Time sounded like it sounded like water running in a dark cave and voices crying and dirt dropping down upon hollow box lids, and rain. And, going further, what did Time look like? Time looked like snow dropping silently into a black room or it looked like a silent film in an ancient theater, one hundred billion faces falling like those New Year balloons, down and down into nothing. That was how Time smelled and looked and sounded. And tonight - Tomás shoved a hand into the wind outside his truck - tonight you could almost touch Time.”—
Whew. I’ve been filming videos for It’s Okay To Be Smart all day today, and I’m tired, so my look at episode 3 of Frankenstein MD (“Anesthetics and Paralytics”) will have to wait until tomorrow! It’s the first time we get to meet Eli and Rory, who are adorbz. Being friends with Victoria seems like a really dangerous prospect.
I’m so excited for today’s premiere of Frankenstein MD that I think I’m going to post each of the first three episodes (which all premiered concurrently) in a row. Maybe with some science-y perspectives, since I am the science advisor for the show.