A Silk Road stopover might have been the epicentre of one of humanity’s most destructive pandemics.

People who died in a fourteenth-century outbreak in what is now Kyrgyzstan were killed by strains of the plague-causing bacterium Yersinia pestis that gave rise to the pathogens responsible several years later for the Black Death, shows a study of ancient genomes.

“It is like finding the place where all the strains come together, like with coronavirus where we have Alpha, Delta, Omicron all coming from this strain in Wuhan,” says Johannes Krause, a palaeogeneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who co-led the study, published on 15 June in Nature.

Fascinating read on new research on the origins of Black Death. As you can imagine, it’s not an easy task to find genomic data from the plague bacteria, several centuries after the pandemic. Then, like now, how the pandemic spread mattered quite a lot of how and where a lot of humans came together and then dispersed, carrying the deadly disease with them.

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Today, a startling new discovery: prodding the brain with light, a group of scientists got an unexpected surprise – they were able to turn back on a part of the brain that had been shut down by Alzheimer’s disease. This new science is not a cure, and is far from a treatment, but it’s a finding so … simple, you won’t be able to shake it. Come join us for a lab visit, where we’ll meet some mice, stare at some light, and come face-to-face with the mystery of memory. We can promise you: by the end, you’ll never think the same way about Christmas lights again.

I’ve been meaning to post about this particular episode ever since I listened to it. This is the Nature paper about this study. They found that simply flashing light of a certain frequency at a certain interval helps with some of the brain waves that are diminished in mice with Alzheimer’s. It’s absolutely fascinating.

(I’m not going into too much technical jargon here; go listen to the episode!)

If you don’t listen to Radiolab in general, you definitely should; it’s one of the best podcasts there are.

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This is from the BBC:

A German biologist who offered €100,000 (£71,350; $106,300) to anyone who could prove that measles is a virus has been ordered by a court to pay up.

Stefan Lanka, who believes the illness is psychosomatic, made the pledge four years ago on his website.

The reward was later claimed by German doctor David Barden, who gathered evidence from various medical studies. Mr Lanka dismissed the findings.

The guy is a biologist? I can understand a non-scientist being deeply skeptical of journal articles and medical findings… but a biologist?

The institution that gave him his degree(s) should consider rescinding whatever degree(s) he has, because:

(a) he clearly cannot review scientific literature and gain an understanding of a subject by himself.

(b) he clearly cannot follow a trail of logic and scientific understanding through published medical research even when it is presented to him by someone else.

Here’s how human society works — we all have our own specializations, and it’s part of our responsibility as specialists to help out others who aren’t knowledgeable in, and cannot tell good from bad, or even have an understanding of, our area of expertise. This isn’t just for “scientists”, of course, but for everyone.

Imagine how little we in general know about the inner workings of our automobiles compared to the expert (mechanic) who’s in charge of fixing them. Now imagine a person who calls himself a mechanic, but (a) doesn’t understand how a certain system in the car works, and (b) cannot follow the logic, and doesn’t believe it when another mechanic shows it to him! Would you ever go solicit this person’s expertise again?

This ‘biologist’ is like our hypothetical mechanic.

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One of my pet peeves with scientific journalism is the propensity to confuse correlation with causation. The idea is that just because two things are observed to happen at the same time (or before, or after, one another), does not imply that one causes the other.

In the latest example of this, the link between chocolate and good health is revisited.

The article opens with:

People who eat chocolate regularly tend to be thinner, new research suggests.

… which implies that a causation has been observed. The article goes on to make the following points:

[…] those who ate chocolate a few times a week were, on average, slimmer than those who ate it occasionally.

The link remained even when other factors, like how much exercise individuals did, were taken into account.

[…] it is how often you eat chocolate that is important, rather than how much of it you eat. The study found no link with quantity consumed.

So… I’d still lose weight if I ate a tonne of chocolate very frequently? Really?!

The most important statement, however, comes a little later:

But the findings only suggest a link - not proof that one factor causes the other.

… and,

And if you are looking to change your diet, you are likely to benefit most from eating more fresh fruits and vegetables.

Now guess what the headline of this article, which itself says that it’s only a link, and talks about maintaining an overall good diet, reads.

Chocolate ‘may help keep people slim’

Perfect, isn’t it?

Most of us have heard of tapeworms, the parasitic creatures that find their way into the human digestive system, and can grow very long indeed. They can cause quite a bit of trouble, but I had no idea how extreme the trouble can sometimes be.

Theodore Nash sees only a few dozen patients a year in his clinic at the National Institutes of Health in Bethesda, Maryland. That’s pretty small as medical practices go, but what his patients lack in number they make up for in the intensity of their symptoms. Some fall into comas. Some are paralyzed down one side of their body. Others can’t walk a straight line. Still others come to Nash partially blind, or with so much fluid in their brain that they need shunts implanted to relieve the pressure. Some lose the ability to speak; many fall into violent seizures.

Underneath this panoply of symptoms is the same cause, captured in the MRI scans that Nash takes of his patients’ brains. Each brain contains one or more whitish blobs. You might guess that these are tumors. But Nash knows the blobs are not made of the patient’s own cells. They are tapeworms. Aliens.

This is scary—they can find their way into the bloodstream, and in the human brain, where they happily live and grow as cysts.

Well, let’s back up a bit. I didn’t know that the tape worm life cycle involves humans and pigs, and that the normal life cycle can only be completed via undercooked pig meat. There you go, I thought, that’s why you should avoid undercooked meat.

But—no. That’s not the half of it.

The more serious trouble (of the brain cyst kind) happens when the normal tapeworm cycle is disrupted. Instead of finding their way inside a pig, tapeworm eggs sometimes find their way straight back inside humans, and the confused eggs behave as they would in a pig—reach for the blood stream. And that’s the recipe for disaster. You could be having tapeworm cysts in your brain, without ever having had raw or undercooked meat.

I won’t give everything away; go read the whole article. It’s excellent, informative, and as I said, a little scary.