Species that reproduce sexually usually need two partners to reproduce, right? Right. What I didn’t know was, females of some species (that usually reproduce sexually) have apparently been observed to be able to reproduce without a mate—rarely, and when they’re in captivity and away from potential mates.

But now, virgin births have been observed in snakes–in the wild, with males present nearby!

They captured pregnant copperhead and cottonmouth female pit-vipers from the field, where males were present.

The snakes gave birth, allowing the scientists to study the physical and genetic characteristics of the litters. […]

“That’s between 2.5 and 5% of litters produced in these populations may be resulting from parthenogenesis.

“That’s quite remarkable for something that has been considered an evolutionary novelty,” he said.

No insights yet on how and why this happens, though, or what implications it may have.

But this is fascinating, nonetheless.

Found this article recently, where they wanted to check how microscopic worms would do in space. Turns out, they do fine—in fact, they actually live longer in space! Additionally:

“We identified seven genes, which were down-regulated in space and whose inactivation extended lifespan under laboratory conditions,” Szewczyk said in a press release. This basically means that seven C. elegans genes usually associated with muscle aging were suppressed when the worms were exposed to a microgravity environment. Also, it appears spaceflight suppresses the accumulation of toxic proteins that normally gets stored inside aging muscle.

They’re not sure what the biological mechanisms might be behind this phenomenon.

I wonder, though—how much of it can be simple chemistry and fluid dynamics? We know that at small enough length scales (such as those of microscopic organisms) viscosity is a much stronger agent than inertia (governed by mass, and to an extent, gravity). Often, gravitational effects are ignored when doing small scale analyses. How do things change in the actual biology when gravity is really zero, not just as an approximation?

Also from the article:

“Most of us know that muscle tends to shrink in space. These latest results suggest that this is almost certainly an adaptive response rather than a pathological one. Counter-intuitively, muscle in space may age better than on Earth. It may also be that spaceflight slows the process of aging.”

I’m not sure why this seems novel. My thought has always been that muscle atrophy in space is due to lack of use, i.e. adaptation. This is why astronauts take special care to exercise their leg muscles while at the International Space Station. The legs no longer need to support the considerable weight of the human body, and the body efficiently starts optimizing its resources!

But perhaps (and most likely) my lack of knowledge allows me to simplify a phenomenon that a physiologist would find many angles to! I’d love to know those angles though—anyone reading this who can help?

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.

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.)

Be careful what you do with your tap water:

The Louisiana Department of Health and Hospitals has issued a weird warning: if you have to irrigate your sinuses with water for some medical reason, don’t use tap water. The reason: your brains may get eaten by the Naegleria fowleri.

Water that you drink is quite all right—even if it contains the bacteria, it will be destroyed when it reaches the stomach and the body’s digestive juices.

But beware if you intend to put water up your nose! This channel is not intended for water (or other food), and does not have the same defense systems as our digestive system does.

The amoeba attacks your nervous system, and can pretty soon leave you dead! Fortunately, the way around is pretty simple: just boil the water to kill the bug!

(My gripe with the article: no source information! No links, whatsoever. Terrible.)