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.

We’re all familiar with the Google home screen, yes? That minimalistic, simple page with essentially nothing but the search box and the search button—seems like great design, doesn’t it? It seems like a well-thought-out decision on what should and should not be on the home page.

Well, guess again:

“We didn’t have a webmaster and I don’t do HTML.”

That’s what Sergey Brin, Google cofounder, is said to have explained.

“He put together the simplest web page he could to test out the search engine back when he was Ph.D. student,” Mayer told a Q&A audience at the 92nd Street Y in Manhattan. “The first version didn’t even have search button because the return button worked just fine. We just kind of stumbled into it.”

That iconic page design—and all because Sergey Brin didn’t care about HTML. (The article has some more tidbits; go read.)

This is an amazing discovery. It’s been known, of course, that some birds (and other animals) are capable of detecting the earth’s magnetic field. This is what gives them a sense of direction, and they seem to know exactly where they are going. Until now, exactly how this detection happened was not completely known, although it was guessed that vision was involved.

Here’s the latest:

This ‘compass’ sense must be associated with the eyeball, because the birds cannot detect magnetic fields in darkness.

But now Oxford University and National University of Singapore scientists have shown that birds may really ‘see’ the invisible force of magnetism, giving them a compass on top of their normal vision: rather like aircraft ‘head up displays’ which overlay crucial navigation information on a transparent screen in front of the pilot.

The ‘technology’, so to speak, involves a special molecule in the eye. When a photon of light enters the eye and hits the molecule, it causes an electromagnetic effect in the eye—and since this effect also depends on the surrounding magnetic field, the effect translates into a ‘map’ of the earth’s magnetic field. All this, right in the eye of the bird!

The next question, I guess, ought to be: is the absence of light the only reason that the birds can’t navigate at night? Would they do fine if there was artificial ambient light at night? What happens if they are fitted out with a ‘headlamp’ of sorts, that reflects light back into their retinas? Is there a minimum amount of light that would be the threshold? This is all very exciting.

In related news, a protein in the human retina has previously been found to possess magnetic properties. This is possibly remnants of the same system—which poses the question: did humans ever have the capacity to detect magnetic fields? Is this a rudimentary evolutionary leftover, or did we shed our sensing capabilities as we gave up our migratory habits and settled down to a life of agriculture?

Really—the more we find out about nature, the more amazing it all is. (Well, granted—the Earth has had a few million years to test and improve new technology, but you’ve got to admit, this is pretty cool.)

Remember the Russian spacecraft—headed for Mars—that failed mysteriously recently not long after takeoff? There were a few suggested reasons for the failure—such as effects due to cosmic rays from the sun, and the result of exposure to US radars

Well, turns out the reasons were more prosaic than that–the craft failed due to a programming error! Two channels of the onboard computer rebooted simultaneously—which evidently they were not supposed to do.

Amazing how the most complex missions can be undone by relatively simpler errors—remember the NASA Mars mission that failed due to a mistake in the units used?