Science

Healthy babies, to be specific.  Because worldwide, infant and child mortality has fallen greatly; and is still falling; and will almost certainly continue to fall.  

In premodern societies, meaning pretty much the entire world before 1820 or so, between a fifth and a quarter of all kids died before their first birthday.  Then, of the survivors, roughly about another fifth-to-a-quarter died before their fifth birthday.  Then, of those survivors, about 10% died before their 20th birthday.  If you do the math, that means that every baby had roughly a coin-flip chance of living to adulthood.  The exact numbers varied by place, time, and circumstances.  But worldwide, that was the general state of affairs.




Today, worldwide about 96% of babies survive their first birthday.  Of all babies born worldwide, about 90% live to reach age 20. 

That’s a worldwide average.  In developed countries, those numbers are “over 99%” and “around 99%”.  In the most dangerous, backwards and unhappy corners of the world the numbers are much lower, but they’re still high by historical standards.  A baby born in Afghanistan or Niger or the Democratic Republic of the Congo today, in 2026?  Has better odds than a baby born in the England of George III and Pitt the Elder.

Nigeria today has an infant mortality rate about what the US had in 1946, when the Baby Boom got started.  The Boom peaked around 1952.  The infant mortality then (a bit over 3%) is about what you find in current-day Bangladesh. Pretty much the entire human race today faces a lower rate of infant mortality than that faced by our parents and grandparents. 

This doesn’t get much discussed, perhaps because it’s a “what about all the planes that land safely” kind of story.   Also, when one discusses long-term positive trends, academic friends may become restive and start murmuring about teleological errors and Whig History. 

But I think it’s really interesting.  That’s partly because it really is very good news, but also — putting my nerd hat on — because this almost certainly represents a permanent and irreversible change in the human condition.

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Bit of a joke there. What the paper is about is, we found a new planet, about 18.2 light years away. That means that we’re seeing the planet as it appeared 18.2 years ago, in the summer of 2007.

Summer 2007: the first iPhone had just hit the market, the last Harry Potter book was fresh on the bookshops, Rihanna’s “Umbrella” was all over the radio, and “The Big Bang Theory” was about to premiere on TV. Britain’s Tony Blair had just handed off to Gordon Brown, while in the US a freshman Senator named Barack Obama was quietly preparing his Presidential bid. And the world economy was sliding inexorably towards the Great Recession.

Anyway, the planet. The planet is a “Super-Earth“. That means it’s basically the same sort of planet as Earth: a ball of rock, probably with an iron core, possibly with an atmosphere. But it’s bigger than Earth, hence the “Super”.  Like, if the Earth was a golf ball, this planet would be more like a cricket ball or a baseball. Definitely bigger, but not so much bigger that it’s a different sort of thing.

Okay, so we’ve found lots of planets around other stars. Like, literally thousands of them.  And we’re finding more new planets every day. So what’s interesting about this one?


[this shows something like one quarter of the currently known planets. and yes, that lower right one is not a proper sphere.]

Well… maybe a couple of things. But first, a brief digression!

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I seem to have become CT’s resident moderate techno-optimist. So let me push back a little: here are five things that we’re not going to see between now and 2050.

1) Nobody is going to Mars. Let me refine that a little: nobody is going to Mars and coming back alive.  A one-way suicide mission is just barely plausible.


[spoiler:  he does get home]

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I do these occasional posts about science papers.  Some are just for fun.  But sometimes — honest! — there’s an underlying connection to the greater Crooked Timber project.

This post is one of that sort, because it’s about the limits of understanding.  Unsurprisingly, it involves biology. 

So we all learned back in high school that our nerves are sheathed in a coating, like insulation on a copper wire. The coating is made of a special substance called myelin.  If your tenth grade biology text mentioned myelin, it probably said something like “myelin allows impulses to flow along the nerves faster and more efficiently”.   Which is true!  It may also do some other things, but “myelin = faster and more efficient transmission” is what we all learned in sophomore biology back when, and it’s basically correct.



Occasionally something goes wrong, and either the myelin sheath doesn’t form right, or the body’s immune system gets confused and attacks it. This can lead to serious problems, conditions like multiple sclerosis and muscular dystrophy. Also, newborn babies haven’t finished forming their myelin sheathing yet.  That’s why newborns are so very weak and uncoordinated. That magic moment, around the three month mark, where the kid suddenly starts holding up their head, looking around, and intentionally reaching for stuff?   That’s when “myelinization” is complete.

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So a few days ago I posted about newts, and I mentioned that there was an American newt that was ridiculously toxic. But then (I said) there wasn’t space or time to go into why.  And of course I was immediately bombarded by many* comments and e-mails asking why. 

*three

Well, fine.  The world’s most toxic newt is Taricha granulosa, the Rough-Skinned Newt, a modest little amphibian native to the North American Pacific Northwest, west of the Cascades from around Santa Cruz, CA up to the Alaska Panhandle.

It’s so toxic that the poison from a single newt can easily kill several adult humans. You could literally die from licking this newt, just once.

(But note that the newt is toxic, not venomous. It doesn’t bite or sting. You could handle one safely, as long as you washed your hands thoroughly afterwards. Very, very thoroughly.)

Okay, but… why?  Lots of newts are mildly toxic.  Why is this particularly newt so extremely toxic?

Turns out this is a fairly deep rabbit hole!  I’ll try to teal deer it.

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So a few days ago I posted about newts, and I mentioned that there was an American newt that was ridiculously toxic. But then (I said) there wasn’t space or time to go into why.  And of course I was immediately bombarded by many* comments and e-mails asking why. 

*three

Well, fine.  The world’s most toxic newt is Taricha granulosa, the Rough-Skinned Newt, a modest little amphibian native to the North American Pacific Northwest, west of the Cascades from around Santa Cruz, CA up to the Alaska Panhandle.

It’s so toxic that the poison from a single newt can easily kill several adult humans. You could literally die from licking this newt, just once.

(But note that the newt is toxic, not venomous. It doesn’t bite or sting. You could handle one safely, as long as you washed your hands thoroughly afterwards. Very, very thoroughly.)

Okay, but… why?  Lots of newts are mildly toxic.  Why is this particularly newt so extremely toxic?

Turns out this is a fairly deep rabbit hole!  I’ll try to teal deer it.

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Unemployed, I spent a week in April digging a small pond in our back yard. At the time, it was a distraction. Now it is… actually, a different sort of distraction.

Because although it’s not a very big pond — about 3 meters by 2, maximum depth about 70 cm — it has very quickly and suddenly filled up with life. The first water skater appeared literally on day one. Now there are about a dozen of them. We’ve also picked up water beetles, a couple of aquatic snails, some little swimming shrimp-like things, and several of these guys:



Ichthyosaura alpestris, “fish-lizard of the Alps”, aka the Alpine Newt.

But how did they get there?
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And then the light of an older heaven was in my eyes
and when my vision cleared, I saw Titans.

— Alan Moore

Today’s Occasional Paper comes to us from the James Webb Space Telescope.

So let’s start with some basics:  nothing can travel faster than the speed of light.  So when a telescope looks out into space, it’s also looking back into time.  Look at the moon?  You’re seeing it as it was when the light left it’s surface about 1.5 seconds ago.  Look at the Sun?  You’re seeing it as it was 8 minutes ago.  The Sun could have exploded 5 minutes ago, and there’s no way you could possibly know about it until 3 minutes from now.

Okay, so keep going.  Look at the nearest star?  You’re seeing it as it was about four years ago.  Look at the center of our galaxy?  30,000 years.  The light from there left around the high point of the last Ice Age.  Look out of our galaxy, at our neighbor galaxy Andromeda?  About 3 million years.

Now it starts to get weird and interesting.  Because as we start to look at things that are billions-with-a-b light years away — very distant galaxies — things start to change.  That’s because we’re looking back into the distant past of the Universe.  And the Universe is only 13.5 billion years old, so… yeah.  In theory, if you had a strong enough telescope, you could see back to the Big Bang and the beginning of everything.

Of course it’s not that simple.  The Universe is expanding.  Distant galaxies are receding from us.  More distant galaxies are receding faster, often at significant fractions of the speed of light (from our perspective).  This means that the distance to them is greater than you might expect.  It also means that their light is “red shifted” by the Doppler effect.  Also, while the Big Bang was very bright, once it cooled down the Universe was just a hot dark cloud of gas, mostly hydrogen with a bit of helium mixed in.  In that earliest pre-dawn epoch, there was not much to see, and no light to see with… until the first stars switched on.

And now for a brief historical digression.

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The blue-ringed octopus! An elegant little creature, native to the southwest Pacific, particularly the waters around Australia. Pretty to look at… but mostly famous for being very, very venomous. The blue-ring’s bite is deadly.  A single sharp nip can kill an adult human in minutes.

But why? The blue-ring is a modest little creature that lives in shallow water, preying on small fish and crustaceans. A bite that can paralyze a 10 gram fish or a 20 gram crab, sure. A bite that can kill a 70 kilogram human dead? What’s the point of that?

Well: the good news is, a recent paper has discovered just why the blue-ringed octopus is so deadly. The bad news is… um, it’s kind of disturbing.

Trigger warning for sexual assault, cannibalism, and existential horror. I am not kidding.

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There’s been a a certain amount of negativity floating around lately. So, let’s talk about a toxic, venomous freak of nature and the parasite that afflicts it.

Biology warning, this gets slightly squicky. [click to continue…]

So my wife took this picture in our garden yesterday, here in Kigali, Rwanda:



Take a close look.  This little bird — about the size of an American cardinal, or a European robin — is facing us.  It’s also facing the sun, though you can’t see that.  It is holding two twigs with its little claws, and… it’s puffing out its breast feathers in a very weird way.  It looks like a breeze is ruffling them.  But there is no breeze.

So we did a quick look-up and found: this is Colius Striatus, the Speckled Mousebird.  Long tail, “scruffy” crest, check.  Thin, rather hairlike breast feathers, check. Very common across tropical Africa, okay.  And then this:  

“Speckled mousebirds… can often be spotted roosting in groups where they’ll buff up their feathers. They do this to allow more sunlight to hit their bodies which helps speed up the fermentation process.”

Wait, what?

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So in the last couple of decades we’ve discovered that many plants rely on networks of soil fungi to bring them critical trace nutrients. This is a symbiotic relationship: the fungal network can access these nutrients much better than plants can, and in return the plants provide the fungus with other stuff — particularly energy, in the form of glucose sugar, made from photosynthesis.

It turns out this relationship is particularly important for large, long-lived trees. That’s because trees spend years as seedlings, struggling in the shade of their bigger relatives. If they’re going to survive, they’ll need help.

The fungal network gives them that help. The fungus not only provides micronutrients, it actually can pump glucose into young seedlings, compensating for the sunlight that they can’t yet reach. This is no small thing, because the fungus can’t produce glucose for itself! Normally it trades nutrients to trees and takes glucose from them in repayment. So it’s reaching into its own stored reserves to keep the baby seedling alive.

Gosh that’s beautiful isn’t Nature great! Well… yes and no.

Because the fungus isn’t doing this selflessly. The nutrients and glucose aren’t a gift. They’re a loan, and the fungus expects to be repaid.

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“You’re always building models. Stone circles. Cathedrals. Pipe-organs. Adding machines. I got no idea why I’m here now, you know that? But if the run goes off tonight, you’ll have finally managed the real thing.”

“I don’t know what you’re talking about.”

“That’s ‘you’ in the collective. Your species.”

— William Gibson, Neuromancer


Sometime in the next 100 days, a star will explode.

The star’s name is T Coronae Borealis, and normally you can’t see it without a telescope: it’s too far away. But when it explodes, you’ll be able to see it just fine. It won’t be the brightest star in the sky, or anything like that. But it will be a reasonably bright star — “second magnitude”, if you’re an astronomer or a nerd — in a place where there was no star before.

It won’t last, of course. The new star — “nova” is the term, which of course just means “new” in Latin — will shine for a few days, then gradually fade back into obscurity.

Maybe you’ve heard of a supernova? Okay, so this isn’t that. This is it’s less spectacular little cousin, the plain and simple nova. A nearby supernova would light up the sky, potentially glowing as bright as the full Moon. This will just be a middling bright star that will (to our eyes) appear from nowhere and then, over a few days or weeks, fade away.

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Here’s a metaphor. There’s an elderly person you’ve known for years.  Not a close relative, no, but someone whose career you’ve followed.  You feel tremendous respect for them, maybe some affection. They’re getting old and frail, but they’ve kept active.  Now and then you might see an article or something, and you’ll think, huh: still with us.

And then something terrible happens, and they’re incapacitated, helpless, unable to speak anything but gibberish. Death seems imminent.

So the family rolls the dice on high risk, experimental brain surgery. And to everyone’s surprise, it works! 

Mostly works. Your friend is still very frail, and they’ve definitely lost a step. The inevitable end has only been delayed.

But — they can speak, slowly but clearly. They can take care of themselves and carry out basic functions. They’re alive. You can talk to them.  They’re even still able to work!  At least, a little.  So you maybe haven’t seen the last article.  It’s an unexpected, surprise reprieve: you have them for a bit longer, another year or two or three.

That’s what it feels like.

So about five hundred million years ago, give or take, there was this little creature called Plectronoceras.  It was about 2 cm long — just under an inch — and it had a conical shell with a bunch of tentacles sticking out.  It was a cephalopod, an early member of the group that includes octopuses and squid.  And it was an /armored/ cephalopod, with most of its soft body protected by that hard little shell.

Let’s pause here and rewind:  this was five hundred million years ago.  That’s the late Cambrian, if you’re a geology nerd.  It’s before the dinosaurs.  It’s before sharks or cockroaches or ferns.  This is *old*.  Complex life had barely gotten started.  Life in general was pretty much confined to the oceans.  But there were no fish yet — just invertebrates.   Half a billion years, yeah?  Long, long time.

And a lot of the stuff swimming around was weirdly alien.  Again, if you’re a geology nerd, you know about stuff like Opabinia, Anomalocaris, or Hallucigenia.  If you don’t, then let’s just say that you wouldn’t have recognized much from those ancient seas.  Not just “no fish”.  There were no clams or lobsters, no starfish or barnacles or crabs or anemones, no coral or kelp.  The world was new.  Those things hadn’t evolved yet.

But almost from the beginning, there was this thing: shell, plus tentacles.

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