arnabocean

— by Arnab Gupta

It doesn’t matter if global warming is man-made

January 12, 2013

Earth’s climate is changing. If you’re not wearing blinkers, and usually follow the news, this should no longer be a controversial statement to you. (Of course, climate change is a better descriptor than global warming. Earth’s temperatures will not literally rise everywhere all the time. Instead, extremes of climates will become more extreme, and the overall nature of Earth’s climate will shift dramatically.)

For example, from this great New York Times piece:

Especially lately. China is enduring its coldest winter in nearly 30 years. Brazil is in the grip of a dreadful heat spell. Eastern Russia is so freezing — minus 50 degrees Fahrenheit, and counting — that the traffic lights recently stopped working in the city of Yakutsk.

Bush fires are raging across Australia, fueled by a record-shattering heat wave. Pakistan was inundated by unexpected flooding in September. A vicious storm bringing rain, snow and floods just struck the Middle East. And in the United States, scientists confirmed this week what people could have figured out simply by going outside: last year was the hottest since records began.

“Each year we have extreme weather, but it’s unusual to have so many extreme events around the world at once,” said Omar Baddour, chief of the data management applications division at the World Meteorological Organization, in Geneva. “The heat wave in Australia; the flooding in the U.K., and most recently the flooding and extensive snowstorm in the Middle East — it’s already a big year in terms of extreme weather calamity.”

Virgin births… in snakes!

November 01, 2012

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.

Of Space Worms

July 21, 2012

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?

☞ Rethinking Dinosaurs

July 21, 2012

The latest in paleontology:

[…] “a filamentous body covering obviously represents the plesiomorphic state for dinosaurs in general,” wrote Rauhut’s team.

Plesiomorphic is another way of saying “ancestrally typical.” In short, it was feathers all the way down.

What?! All two legged dinosaurs had feathers? What were we thinking all these years? Has this been verified?

Now they’ll have to make Jurassic Park all over again.

And all because he didn’t know HTML

March 28, 2012

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.)

Some birds have their own HUDs

March 25, 2012

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.)

Guess why the Russian spacecraft failed…

February 07, 2012

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?

☞ Of the brain-eating amoeba

December 16, 2011

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.)